downstream applications and services of earth observation, satellite navigation and

DOWNSTREAM APPLICATIONS AND SERVICES OF

EARTH OBSERVATION, SATELLITE NAVIGATION AND TELECOMMUNICATION

Tutorial

Author(s): Geoff Busswell, Logica

Nick Green, Logica

Rob Postema, Logica

Reviewer(s): Pat Norris, Logica

Kristo Reinsalu, Invent Baltics

Status: Final

Issued by: Logica

EC.231207-LOG-A-001 Issue 1.0 Date 09 April 2010

© Logica 2010. Copyright statement:

This document contains information which is confidential and of value to Logica. It may be used only for the

agreed purpose for which it has been provided. Logica’s prior written consent is required before any part is

reproduced. Except where indicated otherwise, all names, trade marks, and service marks referred to in this

document are the property of a company in the Logica group or its licensors.

Logica - Downstream Applications and Services of Earth

Observation, Satellite Navigation and Telecommunication

Contents

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CONTENTS

Background 5

1 Earth Observation 7

1.1 Introduction 7

1.2 Where is Earth Observation Used? 7

1.3 Acquisition Techniques 8

1.4 Benefits of Earth Observation 9

1.5 Data Provision 9

1.6 ESA-EC GMES Programme 13

1.7 Service Provision Architecture 16

1.8 Service and Business Models 18

1.9 Examples of Downstream Applications and Services 19

2 Global Navigation Satellite Systems 23

2.1 Introduction 23

2.2 Principle of Satellite Navigation 23

2.2.1 Geometric Principles of Navigation 23

2.2.2 The Navigation Signal 24

2.2.3 Support and Augmentation Signals 25

2.3 Position Errors 28

2.3.1 Atmospheric Effects 29

2.3.2 Multipath Effects 29

2.3.3 Ephemeris Errors 29

2.3.4 Clock Errors 29

2.4 GNSS System of Systems 30

2.4.1 Overview 30

2.4.2 Global Positioning System 30

2.4.3 GLONASS 31

2.4.4 Galileo 31

2.5 Architecture of GNSS based applications and services 32

2.5.1 Overall Architecture 32

2.5.2 Receiver types and performance 32

2.5.3 Mobile Phones 36



Contents

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2.5.4 Communications 37

2.5.5 Back Office 38

2.6 Value chain for GNSS based applications and services 38

2.6.1 Value chain 38

2.6.2 Business Model 39

2.7 Examples of Applications 40

2.7.1 Route-Navigation 40

2.7.2 Tracking and Tracing 40

2.7.3 Surveying 41

2.7.4 Location Based Services 42

2.7.5 Automated/Guided Systems 42

2.7.6 Location based games 42

2.7.7 Precise time reference 42

3 Satellite Telecomunication 43

3.1 Introduction 43

3.2 Satellite Communications Network and its Functioning 43

3.3 Advantages of Satellite Communication 47

3.4 Major Service Categories and Promising Applications 48

3.4.1 Current FSS Services and Applications 49

3.4.2 Current MSS Services and Applications 50

3.4.3 Future trends 53

Abbreviations 56

Glossary 57



Background

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BACKGROUND

Space systems play a notable role in numerous facets of our daily lives, both from a global as well as a

national, Estonian, perspective: each person can watch television programmes reflecting their own

interests; data from earth observation satellites are at the basis of our weather forecasts; satellite

navigation applications are increasingly used in cars and boats, and even in waste management projects

satellite pictures and positioning technology helps to clean our environment. Also medical emergency

situations are coordinated with the same satellite services. These are but a few of the space applications

affecting our life in Estonia. This is an important moment in the history of Estonian space activities. Today,

more than ever before, Estonia has to search for innovative solutions to improve its economy and

functioning of the society. The public is still unaware of the variety, breadth and importance that space

activities play in their everyday lives (Towards an Estonian space policy & strategy, July 2008, p. 5).

There is enormous potential for Estonian industry and organisations to benefit from the development of

applications and services under the two major European space “flagship” programs - Global Monitoring for

Environment and Security (GMES) and Galileo. There could be direct benefits for the emerging Estonian

space community, or indirect benefits for other parts of the space sector and more widely in other sectors of

Estonian economy. In securing these benefits it is important to consider our strengths in order to exploit all

opportunities which both GMES and Galileo could offer in the future. The illustration below (© Euroconsult)

provides an overview on the worldwide revenue in the value chain for earth observation, navigation and

satellite telecommunications.

Estonian Government, industry and the science community have recognised the importance of additional

benefits through the use of space technology applications based on earth observation, satellite navigation

and communication. For this reason Enterprise Estonia (EAS) has initiated an EU financed project;



Background

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“Introduction of downstream applications and opportunities of space technology to the Estonian

entrepreneurs to increase awareness and competitiveness”, which is oriented towards raising space

awareness and building the required capabilities in Estonia.

In the course of the abovementioned “space project”, Invent Baltics and Logica, supported by Black Holes,

organised a seminar on 23rd of September in Tallinn addressing individual entrepreneurs and organisations

interested in developing downstream services or applications, enabled by earth observation, satellite

navigation and telecommunication (EO, SatNav, SatCom), and want to understand its key characteristics

and framework conditions. The seminar was also open to representatives from national and/or international

governmental organisations wishing to understand the key characteristics and framework conditions of

downstream applications of satellite navigation for regulatory, policy or business purposes.

Following this seminar, Logica prepared a tutorial (this document) within the scope of our contract with

Invent Baltics and Enterprise Estonia. The tutorial is based on the seminar materials and collated feedback

from participants of the seminar. The tutorial provides an overview of the elements necessary to develop

downstream applications and services, based on EO, SatNav and SatCom and their introduction into an

operational environment. The tutorial has the following objectives:

• Provide a comprehensive overview of the potential satellite data available from different sources and

possible areas of information used and provided by/through those satellites.

• Introduce the most important technical requirements, specifications etc.

• Present successful examples.

By becoming better acquainted with the abovementioned three fields which are covered comprehensively in

this tutorial, the Estonian space community are provided with:

• An insight to the EO, SatNav and SatCom systems market and perspectives (roadmaps) with the

aim of understanding the niches within which major growth is expected.

• An understanding of the underlying service and business models and prominent players (references

included) in order to introduce an EO, SatNav and/or SatCom service or application successfully.

• An understanding of the scope of an architecture and main elements needed to provide an EO,

SatNav or SatCom downstream service or application to the target customers or users;

• Sufficient information to enable the initiation of EO, SatNav and SatCom related international

projects, and the processes involved (presenting best practice cases where SMEs have been

successful in initiating downstream services cross-border projects).



Earth Observation

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1 EARTH OBSERVATION

1.1 Introduction

Earth Observation can contribute to more efficient use of natural resources worldwide, such as the

management of water resources and forests as well as agricultural practices that are important elements of

social and economic prosperity for populations around the world. Furthermore, remote sensing applications

can provide invaluable input for better exploitation of various energy sources, like wind and solar energy,

through improved data collection. In the context of continuous deforestation and systematic increases in

food prices, Estonia can take advantage of remote sensing applications for planning, estimation and

surveillance in forest management and agriculture. Remote sensing data can provide useful information

about the aerial extent, conditions and boundaries of wetlands. With continuous industrialisation of Estonian

agriculture, the methods of precision agriculture, which is based on remote sensing and positioning

applications, could reduce labour as well as supply costs for farmers. (Towards an Estonian space policy &

strategy, July 2008, p. 26).

It is useful to attempt to define what Earth Observation is. A good definition is:

“The acquisition and exploitation of data from aerial or satellite-based observations of the Earth”.

The following two terms are worth elaborating on:

• Acquisition – collecting data from aerial or satellite-based observations, putting it into a usable

format, and making it accessible to the users of the data

• Exploitation – putting the data to use, e.g. in weather forecasting, flood damage assessment, or

selling posters of famous landmarks seen from space.

1.2 Where is Earth Observation Used?

Earth Observation is used in a variety of market sectors:

• Meteorology & Climate – to provide up-to-the-minute information on weather systems from global to

local/regional scales – this is the best known and most operational form of Earth Observation. Used

for climate science e.g. in analysing global warming trends, greenhouse gases, etc.

• Environmental Monitoring – to check regulation issues on behalf of governments, companies or

individuals; to measure and monitor the Earth's environment; to map resources and pollution; to

observe the influence of mankind on the environment etc. The main sub-domains include

oceanography, the atmosphere, land monitoring, the water cycle, cryosphere & polar regions

• Defence & Security – maps for army, navy and air force for use in wartime or when part of UN

peacekeeping forces; surveillance of enemy positions on the battlefield; detect drug trafficking boats

crossing the ocean, etc.



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• Governments – law enforcement (building regulations, illegal logging, illegal fishing); policy

development

• Commercial – civil engineering, insurance, mapping (multimap etc)

• Public Interest – imagery of earth for public consumption (Google Earth etc)

• Natural Disasters – spot and analyse disasters caused by fire, flooding, landslides, volcanoes, etc

• Agriculture – to see crops growing and map tropical forest coverage

With improvements in technology and acquisition, the list of uses is growing.

1.3 Acquisition Techniques

It is worth summarising the different Earth Observation techniques used with satellites. The techniques can

be split into 5 main types:

• Optical – this is the most well known and is where a satellite measures reflected sunlight from the

ground or ocean. The important point to note is that we rely on the illumination of the sun and so

optical observations are not possible at night. An example application of an optical measurement

might be a town planning project or disaster monitoring (e.g. after-effects of an earthquake).

• Infra-red – this is where the satellite measures the thermal emission from the land or ocean. The

police use this technique from helicopters to detect people (via their body heat) at night. An example

application is to calculate the sea or land surface temperature in a particular region based on the

thermal emission received at the satellite.

• Atmospheric – this is where optical or infra-red radiation from the sun is reflected from the

atmosphere. Most radiation from the sun penetrates the atmosphere and reaches us on the ground,

but a portion is reflected and can be measured by a satellite. Because this technique is reliant on the

sun’s illumination, atmospheric measurements cannot be made at night. Example applications are

measurements of gases in the atmosphere such as carbon dioxide (CO2) or ozone (O3).

• Radar Altimetry – this is where the satellite bounces radar signals (microwaves) of the ground or

ocean and measures the reflected signal (or echo). The measurement is then effectively taken over

a region but averaged to a point. An example application would be the average sea surface height

over a 2500 km2 area. Note that we are not relying on the sun’s illumination here so this technique

can be used day or night and in cloudy conditions.

• Synthetic Aperture Radar (SAR) – this is similar to Altimetry in the sense that microwaves are

bounced off the Earth, but the SAR instrument has many antennas which measure the various echo

waveforms. This information is used to build up a radar image of the source target. As with Altimetry

this technique can also be used day or night and in cloudy conditions. An example application would

be detection and monitoring of oil spills in the ocean.



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1.4 Benefits of Earth Observation

Earth Observation has several benefits to users. Much wider spatial coverage is possible than with

terrestrial/airborne methods as the satellite travels ~10 km/s and can take very frequent measurements

(e.g. 1 observation per second for an Altimeter). Sometimes a satellite will observe a large area such as the

UK, but building up measurements taken over several orbits. In this way spatial coverage of a large area

can be performed much quicker than by using a ground or airborne technique.

Another benefit is that, by using satellites, regular, consistent, repeat coverage can be achieved over

several years. This allows trends over time for a specific region to be analysed over time e.g. forest cover in

South America.

Finally, once a satellite is operational the costs of purchasing data can be much less than obtaining the

equivalent observation from an airplane, vehicle or ship-borne method. It also allows observations in hard-

to-access areas. However, it should be noted that a satellite observation does not always achieve the same

resolution as that of a ground or airborne method.

1.5 Data Provision

In the last 20 years significant achievements have made by space agencies, academic institutions and

commercial companies with regard to the design, manufacture and operations of Earth Observation

satellites as well as the modelling and exploitation of the resulting data. In this tutorial we will focus on the

data provided by satellites associated with ESA and other European countries as well as outlining the main

commercial operators. However, it should be noted that relatively small countries throughout the world

(e.g. Chile, Spain, Kazakhstan, Taiwan, South Korea, Vietnam, and Malaysia) are buying or building their

own satellites and so Estonia might consider this, possibly in collaboration with neighbouring countries.

Figure 1-1 shows a timeline from 1990 to 2010 and beyond with an overview of past, present and planned

future satellites by ESA. The satellites are separated into 3 main groups:

• the area with the blue background shows the meteorological satellites developed in conjunction with

Eumetsat

• the area with the white background shows the Earth Explorer satellites which are designed to help us

better understand our planet (e.g. oceans, gravity and magnetic fields, wind fields, etc.)

• the area with the pink background shows the satellites which are related to applications and services

and is where we concentrate in this tutorial.

Note that the merged shading between the white and pink backgrounds (into orange as we go back in time

towards 1990. This is to illustrate the dual (science and applications) purposes of the ERS and ENVISAT

satellites when they were launched.



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Figure 1-1: Overview of past, present and future ESA related satellites

ERS-1 was launched on July 17th, 1991 and was a major technical accomplishment. It contains several

instruments used to measure various quantities related to the land, sea, ice and atmosphere. ERS-1 came

to the end of its life on March 10th, 2000 lasting far longer than planned. ERS-2 was launched on April 21st,

1995 and contained similar, but improved instruments to ERS-1. This was important to allow cross

comparison of the data between the two satellites. ERS-2 is still operational

ENVISAT was launched on 1st March, 2002 and was the largest EO satellite ever. It was an incredible

achievement and contained 10 different types of instrument. The satellite generates 280 GBytes of data per

day and is expected to be operational until 2011.

One of the major accomplishments of the ERS and ENVISAT satellites was to highlight the issue of climate

change. Data was used to show that small overall increases in the Earth’s climates were affecting the polar

ice caps, sea levels and sea temperature as is shown by Figure 1-2, Figure 1-3 and Figure 1-4.



Earth Observation

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Figure 1-2: The break-up of the Wilkins Ice Shelf between 1992 and 2008

Figure 1-3: Time series graph to show sea level rise between 1992 and 2005



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Figure 1-4: Time series graph to show satellite-derived sea temperature rise from

1992 to 2000

In the commercial market there are several companies who either operate satellites or use the data to

provide a service to public and private sector organisations. Some of the operators will provide satellite data

to the GMES programme (so-called GMES Contributing Mission’s - GCM’s) and these are contained along

with the other GCM’s in Table 1-1. However, since not all the operators will do this it is useful to list the

main commercial satellites and the associated operators:

Mission Type of Mission Operator Launch date

GeoEye-1 Optical GeoEye 2008

GeoEye-2 Optical GeoEye 2012

IKONOS Optical GeoEye 1999

Quickbird Optical DigitalGlobe 2001

WorldView-1 Optical DigitalGlobe 2007

WorldView-2 Optical DigitalGlobe 2009

RADARSAT-2 SAR CSA 2007

TerraSAR-X SAR DLR 2007

TanDEM-X SAR DLR 2010

DMC Optical DMCII 2002

RapidEye Optical MDA 2008



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Mission Type of Mission Operator Launch date

SPOT-4 Optical Spot Image Corp 1999

SPOT-5 Optical Spot Image Corp 2002

Table 1-1: A non-exhaustive list of commercial satellite missions and operators

The biggest operators by far are DigitalGlobe, GeoEye and Spot Image Corporation who focus on high

resolution imagery and together have 63% of the market share. Their largest customer group is

government defence and security agencies, with 62% of data sales coming from this sector. Optical

resolutions will be as high as 25cm for GeoEye-2. The commercial demand for radar observations has also

grown significantly in recent years and the highest resolution images currently are from Radarsat-2 at 1m.

1.6 ESA-EC GMES Programme

GMES is a joint European Commission (EC) and European Space Agency (ESA) initiative that has been

established to fulfil the growing need amongst European policy-makers to access accurate and timely

information services, to better manage the environment, understand and mitigate the effects of climate

change and ensure civil security.

The GMES programme is built on four main pillars:

• Management and requirements of the overall programme is overseen by the EC

• GMES services are managed by the EC.

• GMES Space Component (GSC) is managed by ESA

• GMES in situ (i.e. ground based or airborne) component is managed by the European Environment

Authority (EEA)

The services offered by GMES are split into five main themes:

• Ocean – marine safety and transport, oil spill monitoring, water quality, weather forecasting and the

polar environment,

• Land - water management, agriculture and food security, land-use change, forest monitoring, soil

quality, urban planning and natural protection services

• Emergency response - natural and manmade disasters, flood, forest fire, earthquakes and

humanitarian aid

• Atmosphere - air quality ultraviolet radiation forecasting, and climate change studies

• Security - peace-keeping efforts, maritime surveillance and border control

Figure 1-5 shows the overall architecture of the GMES programme. The in situ and space infrastructures

provide the data which is then fed into various core services. The core services process this data and

provide “added value”, which is the basis for a user service. See the Service Architecture section (1.7) for a



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more complete description of the “added value” concept. An example of a core service might be wave

height as a function of position on the globe.

Figure 1-5: Overall Architecture of the GMES Programme

The downstream services provide specific and niche applications which might use a core service. For

example an application giving surfers in Newquay, England an overview of the surf conditions might utilise

the wave information provided from a core service. Note that users can access both core and downstream

services directly, but a core service would tend to provide a more generic offering than the specialised

downstream services, which are utilised for specific applications.

The GMES Space Component is particularly important to focus on for this tutorial as it is where the satellite

data will come from in the future. Satellite data will come from a series of core sources, called the Sentinel

satellites. There will be five Sentinel satellites:

• Sentinel 1: SAR instrument to provided all-weather, day and night radar imaging to support land and

ocean services. Launch is planned for May 2011.

• Sentinel 2: Optical instrument to provide high resolution imagery to support land services. Launch is

planned for 2012.

• Sentinel 3: Altimeter and optical/infra-red instruments to support ocean and global land monitoring

services. Launch is planned for 2012.

• Sentinel 4: Optical/infra-red instruments to monitor atmospheric composition. This will reside in a

geostationary orbit and will be carried on a Meteosat Third Generation (MSG) satellite operated by

EUMETSAT. Launch is planned for 2017.



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• Sentinel 5: Optical/infra-red instruments to again monitor atmospheric composition, but from a low

earth polar orbit. It is will be carried on the post-EUMETSAT Polar System (EPS) satellite operated by

EUMETSAT. Launch is planned for 2020.

There are also so-called GMES Contributing Missions (GCM’s) which tend to be managed by national space

agencies or commercial entities. They will provide data before and during operations of the Sentinel

satellites to ensure that the whole range of observational requirements are covered. Table 1-2 gives a list of

the current list of GCM’s:

Name of GCM Type of Mission Operator Launch date

ERS-2 All ESA 1995

ENVISAT All ESA 2002

COSMO-SkyMed SAR ASI 2007

RADARSAT-2 SAR CSA 2007

TerraSAR-X SAR DLR 2007

TanDEM-X SAR DLR 2010

DMC Optical DMCII 2002

EnMap Optical DLR 2012

Eros Optical IAI 2000

Pléiades Optical CNES 2010

RapidEye Optical MDA 2008

SEOSAT-INGENIO Optical INTA 2012

SPOT-5 Optical CNES/SNSB 2002

TopSat Optical BNSC 2005

Jason-1 Altimetry NASA/CNES 2001

Jason-2 Altimetry NASA/CNES 2008

Altika Altimetry CNES/ISRO 2010

MSG Atmospheric ESA/EUMETSAT 2002

MetOp Atmospheric ESA/EUMETSAT TBD

Table 1-2: Current list of GMES Contributing Missions

The GMES service segment will be responsible for providing all data and services to users. The service

segment will obtain data from the GMES Space Component Data Access System, which itself is served by

both the Sentinel satellites and the GCM’s. When data is required from a Sentinel satellite a request is made

to the Flight Operations Segment, which incorporates this request into the mission plan.



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Figure 1-6: Overall Architecture of the GMES Space Component Data Access (GSCDA)

System

Once the data is acquired by the satellite it is down-linked to a ground acquisition station and disseminated

to the GSCDA by the Payload Data Ground Segment (PDGS) before it is passed to the service segment,

where it can be sent to the user/organisation. There are, in general, separate PDGS’s and FOS’s for each

Sentinel satellite. Figure 1-6 shows an overall view of the GSC architecture.

More information on the GMES programme can be found on

• http://www.boss4gmes.eu/,

• http://www.esa.int/esaLP/SEMRRI0DU8E_LPgmes_0.html

• http://www.defra.gov.uk/evidence/gi/earthobservation/gmes/index.htm.

1.7 Service Provision Architecture

The provision of an EO service can be broken down into 3 main steps. These are:

• Data Acquisition – the EO data must be obtained (e.g. from ESA’s satellite archive) as well as

necessary auxiliary/ancillary data (e.g. ground control points, in-situ, calibration data etc). The

user/organisation might require access to EO & other data catalogue and ordering systems.

• Data Processing or “Value “Adding” – this is the heart of the downstream service operation and

involves complex algorithms. These algorithms could perform image correction, mosaicing,

mathematical modelling, etc. In general this process requires specialist tools and expertise



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• Product Generation and Dissemination – the processed data must be converted into usable products

that can be easily understood or integrated by the target end-user e.g. web portal/service or ftp.

Requires end-user domain knowledge

A good example of an EO service is provided by the GlobWave project (www.globwave.info). The GlobWave

services will come into operation in Q1, 2010. The main purpose of the project is to process wave data from

a number of European and American satellites into a common format. The tools and readers to ingest the

data will be made available and this will make it much easier to use and compare data from different

sources.

GlobWave gives a real example of each of the stages of the service provision process. The boxes in the top

left of Figure 1-7 are good examples of the data acquisition process. Here, historical and NRT satellite

data and ancillary data (e.g. wind vectors, sea surface temperature info) are ingested into the GlobWave

processor. Also, in situ buoy data, which makes measurements of ocean parameters (such as wave height)

is ingested from various sources.

The value adding step involves several things. Firstly the GlobWave processor transcribes the satellite data

in the common format to give the GlobWave satellite data. The satellite versus in situ processing facility

then looks for overlapping satellite and buoy measurements, and calculates the differences. These

differences help characterise the errors of the satellite measurements and this information is then inserted

back into the relevant GlobWave data products. This means that users can see what the errors are of the

GlobWave satellite data when they have downloaded them. Finally, a satellite versus satellite processing

facility looks for overlaps of satellite observations and calculates the differences.



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Figure 1-7: Service Architecture for Project GlobWave

The product dissemination is performed via the GlobWave web portal. The portal allows users to

download the GlobWave satellite data via online tools or with an ftp service. A monthly quality control report

summarises the statistical differences between the satellite and buoy data. Finally, there is also an annual

report which summarises all the relevant monthly reports as well as giving the statistics of the satellite

observation overlaps.

1.8 Service and Business Models

There are a number of possible service models via which EO data can be disseminated. These could be:

• Routine – data is delivered at regular intervals e.g. crop health monitoring may require

monthly/fortnightly data generation during the growing season, less frequent at other times

• On-demand (low priority) – customer places non-urgent ad-hoc order for a specific image or product

e.g. town planning project

• On-demand (high priority) – customer places urgent ad-hoc order e.g. e.g. emergency response

situations, security applications

• Automated browsing – service provider can use software to browse product data for those of interest

e.g. rogue wave analysis where you don’t know where they are going to be in advance, or



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identifying places where a quantity has changed by more than a required amount such as wind

speed or sea surface temperature.

The types of business models are centred around recovering the costs of the satellite development, launch

and maintenance. This is critical to enabling a viable business case. Possible business models are:

• Subscription based service – the customer pays for regular delivery of the data. It is possible that

certain regions may be in demand e.g. an oil platform location

• Pay-per-product – low priority orders (<24 hours) would cost less than high priority ones (< 1hour).

The customer might pay more for specific constraints on the data e.g. <1% cloud coverage for an

optical image

• Pay-per region – this is where a customer requires data coverage of a large area e.g. whole of

Europe. This would cost much more than a single data acquisition because a large region would

require several weeks of satellite overpasses.

• Pay-per-target constraint – this is where you don’t have a specific region in mind but want the data

to satisfy a particular constraint e.g. a shipping company wants to know whenever there is a 50m

wave in the North Atlantic or an oil company wants to know if there is a sudden change in the

position of a rig. This could also be relatively expensive because the service provider much search all

required data in the region of interest. Possible payment schemes involve a one-off payment for the

data search with thumbnails offered to the users. For each thumbnail they choose to purchase they

are charged supplementary amounts.

• Free services – The more basic services could be offered free and perhaps demonstrations could be

offered of the more complex services over a trial period. The free services in particular are something

Google and Microsoft have championed with IT services (such as email, mapping) and these are

funded by advertising.

1.9 Examples of Downstream Applications and Services

In this section we present various examples of where EO data is being (or has been) used.

Characterisation of Digital Elevation Models

This is one of many services offered by Fugro NPA, which

allows customers to know the height of the terrain in regions of

interest.

For example oil companies could use this to determine pipeline

routing or the mining industry could plan a drilling campaign.

Resolutions range from 50cm in the optical up to 30m using

radar observations.



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Monitoring landslides triggered by Earthquakes

This is work performed by the University of Durham, UK. The

Wenchman Earthquake occurred on 12th May, 2008 in Sichman

Province, China and measured 7.9 on the Richter scale.

Preliminary reports suggested tens to hundreds of landslides

were triggered. The motivation of the work is to try and

understand the geological process associated with natural

hazards.

The methodology is to use EO data to examine the spatial

distribution of landslides and then to perform statistical analysis

to correlate the landslides with geological variables such as

earthquake magnitude, slope angle, geology type, etc. The goal

is to be able to predict a likely landslide scenario as a result of

a future earthquake.

Impact Crater Discovery

This is work carried out by Logica for ESA and involves the

processing of EO data to automatically recognize craters on

Earth caused by the impact of large meteorites, asteroids and

comets.

The image shows an impact crater in Gosses Bluff, Central

Australia with the circle illustrating the vector automatically

extracted by Logica software.

Potato Farming

The British Potato Council contracted Logica to verify the

acreage-related fees to be paid by Britain’s potato farmers.

Logica processed EO imagery to show in-field variations in crop

vigour, providing a good indication of crop health and potential

yield.



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Atmospheric CO2

The University of Leicester, UK has been investigating the CO2

content in the atmosphere using a combination of satellite and

in situ measurement devices. Networks of in situ CO2 sensors

provide accurate measurements of global CO2 but such

measurements are too sparse to allow accurate measurements

on a sub-continent scale.

EO infra-red measurements from instruments such as

SCIAMACHY (on the ENVISAT satellite) can measure CO2

concentration in the atmosphere allowing much better

characterisation of CO2 content on large scales. Due to this and

other work scientists now believe that human activity has led to

large increases in atmospheric CO2, from 280 ppm to 386 ppm

over the “industrial period” so far.

Subsidence Mapping of the Yellow River Delta

The University of Glasgow has been using EO SAR imaging to

investigate subsidence in the Yellow River Delta region in

China. The subsidence is thought to be a result of the

petroleum, natural gas and water withdrawal.

Class “spirit level” measurements show subsidence of 0.3-0.5m

in several oilfields over the 11 year period between 1986 and

1997. The satellite based SAR images allow high resolution

spatial sampling over a large area with sub-cm accuracy.

Penguin Monitoring

This is work performed by the British Antarctic Society who is

studying the penguin breeding process. This occurs during

winter in a small number of isolated colonies around the coast

of Antarctica.

However, it is difficult to get scientists there during the winter

period because of the weather and by spring the evidence has

been lost as the sea ice breaks up. Optical satellite data (from

Landsat and Quickbird) is therefore very useful to help detect

and assess colony sizes.

EO Data in the Insurance Sector

Logica is developing the use of EO for the insurance market in

the UK. They are working with major names such as Lloyds and

Willis Insurance. Areas of interest include hurricanes, floods,

storms, fires, ‘before and after’ comparisons, risk assessments

etc.



Earth Observation

EC.231207-LOG-A-001 / 1.0 page 22 of 58

Monitoring of Woodland

This work performed by the University of Salford who are

working to characterise the amount of green areas in forest

regions using a statistic called the Leaf Area Index (LAI).

Ground measurements are necessary but it takes a long time to

make observations over a large area.

Optical data from the DMC allows vegetation to be mapped to a

resolution of 32 metres. The satellite observations allow large

regions to be covered extremely quickly. The DMC was used to

measure LAI every two weeks during 2005 and the results

agreed well the ground measurements.

Burned Area Severity in Tropical Forests

The University of Leicester, UK has looked at the frequency of

fires in tropical forests. In recent years it is thought that such

fires have become more frequent and widespread.

There was a need to measure the burn severity and investigate

how the vegetation recovers after the fire. The type, amount

and quality of fuel available for future fires were also

investigated. During this work infra red Landsat images of pre

and post fire regions was correlated with post fire in situ

measurements collected several years after the fire.



Global Navigation Satellite Systems

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2 GLOBAL NAVIGATION SATELLITE SYSTEMS

2.1 Introduction

Satellite navigation and positioning is the process of determining your location on earth with the use of

satellites. It is a common misunderstanding that these satellites can track and trace someone or something

on earth. This is not possible, only the receiver knows its position. However if the receiver is equipped with a

connection to a back office it can reveal its location. An extra feature of satellite navigation is the ability of

clock synchronization by using the satellites time signal.

Global Navigation Satellite Systems (GNSS) have quickly become a standard feature in everything from

search and rescue services to automobile navigation and leisure goods. The value of location-based services

is strongly influenced by the accuracy of the positioning technology used. When Galileo becomes

operational, the available positioning accuracy will be greater than with GPS and because of the availability

of different service classes and service guarantees provided, the palette of potential applications will be

much larger as well.

The steady increase in commuter traffic in all parts of the world, including Estonia, creates multiple

challenges for sustainable growth. Space-based solutions, notably the use of global navigation satellite

systems (GNSS) and satellite telecommunications, may increasingly help to meet these mobility challenges.

The ability to determine accurately and communicate one’s position at any moment thanks to GNSS is

starting to have a major impact on the management of ship and track fleets, road and rail traffic

monitoring, mobilisation of emergency services, tracking of goods carried by multimodal transport and air

traffic control (Towards an Estonian space policy & strategy, July 2008, p. 27-28).

2.2 Principle of Satellite Navigation

2.2.1 Geometric Principles of Navigation

In this section it is explained how the receiver determines its location. The receiver calculates the distance to

the GPS-satellite by measuring the travel time of the signal. The travel time is the time between

transmission of the signal from the satellite and the time of arrival at the receiver. The radio signal travels

with the speed of light and the travelled distance is calculated by multiplying the speed of light with the

travel time. A sphere, with the satellite as centre and the travel distance as radius, describes all possible

locations of the receiver.

Figure 2-1 shows that when the distance is known to three satellites the receiver’s location is at the

intersection of those three ranging spheres. Geometry states that three spheres can mutually intersect at

no more than two points. Only one of those positions will be close enough to the earth to be the receiver’s

position.




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Figure 2-1: The geometric principles of positioning

Since the receiver does not have an atomic clock like the satellite, its clock time needs to be synchronized

with the GPS-satellites. The receiver uses a fourth satellite for this synchronization.

2.2.2 The Navigation Signal

GPS satellites broadcast three different types of

data in the navigation signals. The first is the

almanac data, which contains all coarse time

information along with status information about

the satellites. This data is current for several

months, so not very accurate. The second is the

ephemeris, which contains orbital information

and clock corrections that allows the receiver to

calculate the position of the satellite at any point

in time. These bits of data are folded into the

37,500 bit Navigation Message, or NM, which

takes 12.5 minutes to send at 50 Hz. The

mixing of signals is shown in the diagram

opposite.

Third, the satellites also broadcast two forms of accurate clock information, the Coarse Acquisition code, or

C/A, and the military Precise code, or P(Y)-code. The former is normally used for most civilian navigation. It

consists of a 1,023 bit long pseudo-random code broadcast at 1.023 MHz, repeated every millisecond. Each

satellite sends a distinct C/A code, which allows it to be identified. The military P(Y)-code is a similar code

broadcast at 10.23 MHz, but encrypted and can only be decrypted by units with a valid decryption key. All

three signals, NM, C/A and P(Y), are mixed together and sent on the primary radio channel, L1, at 1575.42

MHz. The military P(Y) signal is also broadcast alone on the L2 channel, 1227.60 MHz.




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2.2.3 Support and Augmentation Signals

2.2.3.1 Differential Techniques

Differential technique is an augmentation to GPS. It uses a ground based reference station with a known

position and calculates its difference between this position and the position indicated by the satellite

systems. These differential measurements can be based on the mono or dual frequency measurements

using code or carrier phase techniques. These corrections are broadcasted and receiver units that are

capable of receiving this differential signal use it to correct their position measurement to obtain higher

accuracy.

There are several systems broadcasting these corrections. The type of broadcast can be on a short-range

radio frequency, satellite broadcast or even through GSM or internet (GPRS/UMTS). They differ on the type

of connection, costs and the reached accuracy.

Three varieties of the differential technique are explained in more detail:

Satellite Based Augmentation System

A Satellite Based Augmentation System (SBAS) is a system that supports wide-area or regional

augmentation through the use of additional satellite-broadcast messages. Such systems are commonly

composed of multiple ground stations, located at accurately-surveyed points. The ground stations take

measurements of one or more of the GNSS satellites, the satellite signals, or other environmental factors

which may impact the signal received by the users. Using these measurements, information messages are

created and sent to one or more satellites for broadcast to the end users.

While SBAS designs and implementations may vary widely, with SBAS being a general term referring to

any such satellite-based augmentation system, under the International Civil Aviation Organization (ICAO)

rules a SBAS must transmit a specific message format and frequency which matches the design of the

United States' Wide Area Augmentation System

EGNOS is the European SBAS. This system uses 30 reference stations spread over Europe to build up

differential corrections. These corrections are broadcast via geostationary satellites covering the European

region. Using EGNOS an accuracy of 3-5 meter is reached.

Besides differential data, integrity data is also included in the signal. This tells the receiver which navigation

satellite malfunctions so the receiver can ignore it. Similar systems are operational in the USA (WAAS), and

Asia (MSAS). The use of these systems is free of charge, but special receivers are needed. There are also

three commercial SBAS systems: VERIPOS, StarFire and OmniSTAR.

Ground Based Augmentation

Each of the terms Ground Based Augmentation System (GBAS) and Ground-based Regional

Augmentation System (GRAS) describe a system that supports augmentation through the use of

terrestrial radio messages. As with the satellite based augmentation systems detailed above, ground based

augmentation systems are commonly composed of one or more accurately surveyed ground stations,




EC.231207-LOG-A-001 / 1.0 page 26 of 58

which take measurements concerning the GNSS, and one or more radio transmitters, which transmit the

information directly to the end user.

The term Differential GPS can refer to both the general differential technique, as well as specific

implementations of it. It is often used to refer specifically to systems that re-broadcast the corrections from

ground-based transmitters of shorter range. For instance, the United States Coast Guard runs one such

system in the US and Canada on the radio frequencies between 285 kHz and 325 kHz. These frequencies

are commonly used for marine radio, and are broadcast near major waterways and harbours. Similar

systems are globally available at the coast. The International Association of Lighthouse Authorities (IALA)

organises the global availability of MF radio beacons.

The accuracy of the system depends on the distance of the user to the reference station. For radio-DGPS a

typical accuracy of 2 meters is used. Although an accuracy of sub-meters can be achieved.

Figure 2-2: DGPS reference station providing differential correction data

Several commercial providers make use of GSM or internet to supply users with differential data. 06-GPS

and Globalcom provide full coverage of the Netherlands. Due to the fine grid sub-meter accuracy is

achieved.

Virtual Reference Station

The Virtual Reference Station (VRS) method extends the use of DGPS to a whole area of a reference station

network. Operational reliability and the accuracies to be achieved depend on the density and capabilities of

the reference station network. For all locations the differential corrections are interpolated from the closest

reference stations. 06-GPS claims an accuracy of 20 cm horizontally and 30 cm vertically. It provides the

differential data through the internet. A contract is needed to access the data.




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In the Netherlands a network of reference stations providing the VRS method is available through NETPOS

(RTK), 06-GPS and LNR Globalcom. Similar networks are available in our neighbouring countries: SAPOS

(Germany), FLEPOS (Belgium).

Real Time Kinematic

Real Time Kinematic (RTK) satellite navigation is a technique used in land survey. RTK is based on the use

of carrier phase measurements of the GPS, GLONASS and in future Galileo signals, where a single reference

station provides real-time corrections resulting in a centimetre level of accuracy. When referring to GPS in

particular, the system is also commonly referred to as Carrier-Phase Enhancement, CPGPS.

In practice, RTK systems use a single base station receiver and a number of mobile units. The base station

re-broadcasts the phase of the carrier that it measured, and the mobile units compare their phase

measurements with the ones received from the base station. This allows the units to calculate their relative

position to millimetres, although their absolute position is accurate only to the same accuracy as the

position of the base station. The typical nominal accuracy for these dual-frequency systems is 2 centimetres

horizontally and 3 centimetres vertically.

Although this limits the usefulness of the RTK technique in terms of general navigation, it is perfectly suited

to roles like surveying. In this case, the base station is located at a known surveyed location, often a

benchmark, and the mobile units can then produce a highly accurate map by taking fixes relative to that

point. RTK has also found uses in autodrive/autopilot systems, precision farming and similar roles.

Like with DGPS, the RTK system can also use a network of reference stations. NETPOS (government), 06-

GPS and LNR-Globalcom (commercial) provide these systems. NETPOS broadcasts the RTK-differential data

short-range radio frequencies and 06-GPS offers the data over a GSM/GPRS connection.




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Figure 2-3: Network of Reference Stations as deployed by 06 - GPS in the Netherlands

2.2.3.2 Assisted GPS

Assisted GPS or AGPS provides the receiver with almanac and ephemeris data. Normally this is downloaded

from the GPS satellite. This satellite data stream has a very slow rate of 50bits/second, which is the reason

why it often takes several minutes for conventional GPS receivers to download the required data from the

satellite before computing its own location (cold start). The AGPS server can provide the data via a cell

tower through GSM/GPRS techniques, but also through the internet.

In some systems the AGPS receivers send the raw GPS signal to the AGPS server. This server has high

processing power available to compute the position, which is returned to the receiver. An advantage here is

the low power consumption of the receiver. Various AGPS services provide next to the almanac data also

differential data and satellite integrity data.

2.3 Position Errors

The position calculated by a receiver is influenced by several error sources. In the table below the most

important effects are outlined, with descriptions following.




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Source Effect

Ionospheric effects ± 5 meter

Ephemeris errors ± 2.5 meter

Satellite clock errors ± 2 meter

Multi-path distortion ± 1 meter

Tropospheric effects ± 0.5 meter

Numerical errors ± 1 meter

Table 2-1: Sources of Errors

When adding up all error sources GPS is typically accurate to about 15 meters.

2.3.1 Atmospheric Effects

The largest error is due to time delay, caused by the slowing down of the signal (time delay) by the

atmosphere. Receivers use an internal mathematical model to apply an estimated correction for the error,

which reduces the error to around 5 meters. Additionally, military and expensive survey-grade civilian

receivers can compare the difference in delay between the L1 and L2 frequencies to measure this

atmospheric delay and apply precise corrections. This is possible because the ionosphere has a frequency

dependent effect on the speed of radio waves.

2.3.2 Multipath Effects

GPS signals can also be affected by multi-path issues, where the radio signals reflect off surrounding

terrain; buildings, canyon walls, hard ground, etc. This delay in reaching the receiver causes inaccuracy. A

variety of receiver techniques have been developed to mitigate multi-path errors. For long delay multi-path,

the receiver itself can recognize the wayward signal and discard it. To address shorter delay multi-path from

the signal reflecting off the ground, specialized antennas may be used. This form of multi-path is harder to

filter out since it is only slightly delayed as compared to the direct signal, causing effects almost

indistinguishable from routine fluctuations in atmospheric delay.

Multi-path effects are much less severe in dynamic applications such as cars and planes. When the GPS

antenna is moving, the false solutions using reflected signals quickly fail to converge and only the direct

signals result in stable solutions.

2.3.3 Ephemeris Errors

The navigation message from a satellite is sent out every 12.5 minutes. However, the data contained in

these messages tends to be "out of date" up to 5 hours. Consider the case when a GPS satellite is boosted

back into a proper orbit; for some time following the manoeuvre, the receiver’s calculation of the satellite's

position will be incorrect until it receives another ephemeris update.

2.3.4 Clock Errors




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Further, while it is true that the onboard clocks are extremely accurate, they do suffer from clock drift. This

problem tends to be very small, but may add up to 2 meters of inaccuracy.

Ephemeris and clock errors are more "stable" than ionospheric effects and tend to change on the order of

days or weeks, as opposed to minutes. This makes correcting for these errors fairly simple by sending out a

more accurate almanac on a separate channel (Assisted-GPS).

2.4 GNSS System of Systems

2.4.1 Overview

Figure 2-4 provides an overview of the current GNSS augmentation systems.

Figure 2-4: Overview of GNSS satellite and augmentation systems

2.4.2 Global Positioning System

The Global Positioning System, usually called GPS, is the only fully-functional satellite navigation system. A

constellation of more than 24 GPS satellites broadcasts precise timing signals by radio waves to GPS

receivers, allowing them to accurately determine their location (longitude, latitude and altitude) in any

weather, day or night, anywhere on earth.

The United States Department of Defense developed the system, officially named NAVSTAR GPS

(Navigation Signal Timing And Ranging GPS), and launched the first experimental satellite in 1978. The

satellite constellation is managed by the 50th Space Wing. Although the costs of maintaining the system are

approximately US$400 million per year, including the replacement of aging satellites, GPS is available for

free use in civilian applications.

In late 2005, the first in a series of next-generation GPS satellites was added to the constellation, offering

several new capabilities, including a second civilian GPS signal called L2C for enhanced accuracy and

reliability. In the coming years, additional next-generation satellites will increase coverage of L2C and add a

third and fourth civilian signal to the system, as well as advanced military capabilities.




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One of the issues with GPS is that the system is a military system. The US-army can decide to decrease the

accuracy because of war or political issues.

2.4.3 GLONASS

GLONASS (ГЛОНАСС) is the Russian counterpart to the United States' GPS system. This satellite navigation

system is operated for the Russian government by the Russian Space Forces.

The system is designed to consist of 24 satellites, 21 operating and three on-orbit 'spares' and placed in

three orbital planes at an altitude of 19,100 km, which is slightly lower than that of the GPS satellites. Each

satellite completes an orbit in approximately 11 hours, 15 minutes.

The system was intended to be operational in 1991 but the constellation was not completed until December

1995. However, due to the economic situation in Russia there were only eight satellites in operation in April

2002 rendering it almost useless as a global navigation aid.

At present 18 satellites are operational, and a full system is expected this year. GLONASS is likely to be

important for Russia, Belarus and other countries in the Russian sphere of influence.

Additionally, following a joint venture deal with the Indian Government it was proposed to have the system

fully operational again by 2008 with 18 satellites, providing full coverage of Russian territory and by 2010 a

global coverage with all 24 satellites.

2.4.4 Galileo

Galileo will be Europe’s own global navigation satellite system, providing a highly accurate, guaranteed

global positioning service under civilian control.

The Galileo system is planned to be fully operational in 2014 and consists of 30 satellites, 27 operational + 3

active spares, positioned in three circular planes at 23 222 km altitude at an inclination of 56 degrees. Once

this is achieved, the Galileo navigation signals will provide good coverage even at latitudes up to 75 degrees

north, which corresponds to the North Cape, and beyond. Compared to GPS this will be a major

improvement to the coverage in the countries in northern Europe, such as Norway and Sweden.

There are several more advantages of Galileo compared to GPS and GLONASS:

• The Galileo satellites will broadcast integrity data, which informs users within seconds of mall

functioning of any satellite. This will make Galileo suitable for applications where safety is crucial,

such as running trains, guided cars and landing aircrafts. The integrity data will be composed at 20

Galileo Sensor Stations spread over Europe.

• Galileo supplies a subscription in which it will guarantee availability of the service. The availability of

GPS can be reduced by the US-army, like they did during the war in Iraq.

• Galileo’s open service is like GPS available free of charge to the public. Additionally, Galileo offers

within the open service the so-called dual-frequency service. With a dual-frequency supporting

receiver the accuracy improves from around 20 meters to 5 meters. In the coming years, additional

next-generation GPS satellites will also include a second civilian signal (L2C). All systems are

planning to add a third and fourth civilian signal to the system in the future.




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• Galileo is under civilian control and there for independent of war or political issues. This in contrary to

the military GPS and GLONASS systems.

One of the main advantages is in de growth of the number of positioning satellites Galileo will be inter-

operable with GPS and GLONASS. This means that when all systems are fully operational about 80

navigation satellites will be available. With receivers able to receive more systems, accuracy will increase

and effects due to atmosphere and multipath will be reduced.

As a further feature, Galileo will provide a global Search and Rescue (SAR) function, based on the

operational Cospas-Sarsat system. To do so, each satellite will be equipped with a transponder, which is

able to transfer the distress signals from the user transmitters to the Rescue Coordination Centre, which will

then initiate the rescue operation. At the same time, the system will provide a signal to the user, informing

him that his situation has been detected and that help is under way. This latter feature is new and is

considered a major upgrade compared to the existing system, which does not provide a feedback to the

user.

2.5 Architecture of GNSS based applications and services

2.5.1 Overall Architecture

Figure 2-5 provides an overview of service provision architecture of a GNSS based application and service.

Figure 2-5: Service provision architecture of GNSS based applications and services

2.5.2 Receiver types and performance

The accuracy of the estimated location depends among others on the techniques used in the receiver. The

receiver can use mono or dual-frequency, combined with code-phase or carrier-phase. This section gives a

short explanation of these methods.




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2.5.2.1 Single/Dual Frequency

The GPS signal is transmitted over two different carrier frequencies called L1 and L2.

The single-frequency receivers only use the L1 band. These are the most commonly used low-cost

receivers, which are implemented in all mass navigation applications. These receivers reach an accuracy of

around 20 meters.

Dual frequency means that the receiver, besides the standard L1 signal also receives the L2 frequency. By

comparing the delays of these two signals a correction is made for the ionospheric delay, which results in a

more accurate position with an accuracy around 5 meter. In the past only the US-military and its NATO

members had access to the signals on the L2 carrier. Nowadays, with the modernisation of GPS the L2

carrier is made available for the public. However global coverage is not reached because of delay in the

replacement of the satellites. The uncertainty on the date of global availability is the reason of the lack of

mass-production of low-cost dual-receivers. Dual-frequency requires a very sophisticated and thus

expensive receiver.

In Galileo the two different carrier frequencies will both be available within the open signal. This makes the

dual-frequency technique available to the public for free. At the moment, the designers of Galileo are

examining the option to add a third civilian frequency to the system.

2.5.2.2 Code-Phase

Standard GPS receivers make use of a pseudo-random code, which is modulated in the carrier frequency L1

(1.57 GHz). This code is repeated every millisecond and compared to an identical code generated by the

receiver. From this comparison the receiver calculates the travel time of the signal.

Figure 2-6: Standard receivers use de pseudo-random code to determine the travel

time of the signal (source: www.trimble.com)

This technique is very sensitive for positioning errors and has a theoretic error of around 300m, but with the

use of smart receivers the error is reduced to 3-6 meters. The most common and low-cost receivers make

use of the code-phase technique. This receiver error is just a part of the position error, errors due to

ionospheric delay and a time error need to be added. The total error with a low cost single-frequency

receiver in a GPS-only system is 10-20m.




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2.5.2.3 Carrier-Phase

The carrier-phase technique is a highly sophisticated technique and is only used in expensive receivers.

These receivers start with the pseudo random code, like with code-phase, but now move on to

measurements based on the carrier frequency. This frequency is much higher so its pulses are much closer

together and therefore more accurate, see Figure 2-7. Expensive code-phase receivers in combination with

augmented systems can reach a very high accuracy around centimetres.

Figure 2-7: The carrier-phase technique uses the carrier signal to determine the

signals travel time (source: www.trimble.com)

2.5.2.4 Additional augmentations of the signal

As indicated in Figure 2-4, additional techniques are available to improve the position accuracy, time to first

fix, and reliability:

• Differential Global Positioning System (DGPS) is an enhancement to Global Positioning System that

uses a network of fixed, ground-based reference stations to determine and broadcast the difference

between the positions indicated by the satellite systems and the known fixed positions. This

difference can be forwarded to the receiver, either via a dedicated network, or available networks

such a cellular networks or WLAN. Generally, GBAS (Ground Based Augmentation System) networks

are considered localized, supporting receivers within 20km, and transmitting in the Very High

Frequency (VHF) or Ultra High Frequency (UHF) bands. GRAS (Ground-based Regional

Augmentation System) is applied to systems that support a larger, regional area, and also transmit

in the VHF bands.

• Wide Area Augmentation System (WAAS) uses a network of ground-based reference stations to

measure small variations in the GPS satellites' signals. Measurements from the reference stations are

routed to master stations, which queue the received Deviation Correction (DC) and send the

correction messages to geostationary WAAS satellites in a timely manner. Those satellites broadcast

the correction messages back to Earth, where WAAS-enabled GPS receivers use the corrections

while computing their positions to improve accuracy. An example of a WAAS is the EGNOS service.

• Mapmatching is the functionality where a measured position is linked to the nearest road. Based on

subsequent measurements, driving direction can be determined. This technology is e.g. applicable in

route navigation.




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• Relative Kinematic Positioning (RKP) is another approach for a precise GPS-based positioning

system. In this approach, determination of range signal can be resolved to a precision of less than

10 centimetres (4 inches). This is done by resolving the number of cycles in which the signal is

transmitted and received by the receiver. This can be accomplished by using a combination of

differential GPS (DGPS) correction data, transmitting GPS signal phase information and ambiguity

resolution techniques via statistical tests—possibly with processing in real-time (real-time kinematic

positioning, RTK).

• RAIM is the abbreviation for Receiver Autonomous Integrity Monitoring, a technology developed to

assess the integrity of GPS signals in a GPS receiver system. It is of special importance in safety-

critical GPS applications, such as in aviation or marine navigation. RAIM detects faults with

redundant GPS pseudorange measurements. That is, when more satellites are available than needed

to produce a position fix, the extra pseudoranges should all be consistent with the computed

position. A pseudorange that differs significantly from the expected value (i.e. an outlier) may

indicate a fault of the associated satellite or another signal integrity problem (e.g. ionospheric

dispersion).

• An Inertial Navigation System (INS) is a navigation aid that uses motion sensors (accelerometers)

and rotation sensors (gyroscopes) to continuously calculate the position, orientation, and velocity

(direction and speed of movement) of a moving object without the need for external references,

based on its measured acceleration and rotation. It is used on vehicles such as ships, aircraft,

submarines, guided missiles, and spacecraft. It is used in GNSS receiver in case of loss of signal, to

provide continuity of position and speed. Furthermore, it can be used to improve the determination

of position.

• Assisted GPS, generally abbreviated as A-GPS, is a system which can improve the startup

performance of a GPS satellite-based positioning system. It is used extensively with GPS-capable

cellular phones.

2.5.2.5 Selection criteria for receivers

Figure 2-8 provides a qualitative relation between accuracy and costs of the GNSS receivers. The trend will

be that the overall price of the GNSS receivers will go down.

Selection criteria for the GNSS receiver are indicated and very much depend on the type of application

which needs to be realised:

• For LBS, in most cases the mass markets is addressed, and with mobile phones power consumption

needs to be very low. As such, low price, low accuracy (15 m) receivers will be selected. With the

availability and interoperability of Galileo with GPS, improved accuracy will be possible.

• For mission and safety critical applications, reliability of the positioning and availability of the signal is

key, so receivers fit for this purpose will be selected, which are more expensive. In the case of an

increase in accuracy and a switch to dual band receiver, prices go up.




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• For mobile phones, and also for GPS receivers in for example watches etc. dimensions are very

small. Miniaturisation at this moment will increase the price. However, with the addressable market

in mobile phones, in-car units and GPS enabled gadgets, prices are expected to drop soon.

Figure 2-8: Pricing vs. Accuracy of GNSS Receivers, and a first cut overview of

selection criteria

2.5.3 Mobile Phones

With the growth of mobile phones including a GNSS receiver, the potential for offering LBS grows rapidly,

see Figure 2-8.

Figure 2-9: Growth in GNSS enabled mobile phones, key in LOBS




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The challenge for the developers of mobile phone LBS is to provide and maintain the applications for several

available mobile phone platforms; iPhone, Symbian, Google Andriod and Mobile Windows. Several

developers offer GNSS based applications for these platforms. The challenge, however, is that for

professional services providers, and commercial operations, the applications need to be developed for all the

platforms, imposing additional effort to develop them. As a consequence, an increasing number of service

providers choose to develop web based applications for mobile phones, served by the mobile internet.

2.5.4 Communications

In order to provide the end user with information based on their location, time and personal preferences,

two options are available for the services provision architecture:

• All information necessary for the LBS is present on the mobile device. Advantages are the

independence from availability of communication, quick access to data, and security. Disadvantages

are that information is less dynamic, and information is limited due to the storage capability of the

mobile phone. Also, the LBS is limited to the user of the mobile phone - there is no link with other

mobile users, e.g. for social network (friend finder). The communication link is often used to update

the information off-line at regular intervals. This can be performed via a wireless link or through

connection to the internet via a host computer.

• All information is stored in a back office, and is retracted based on user profile, time and location

through a communication link. In this case, and for the update of local information, several

communication means are available, as indicated in Figure 2-10.

Figure 2-10: Overview of communication means for location based services,

presenting characteristics and an overview of the selection criteria.




EC.231207-LOG-A-001 / 1.0 page 38 of 58

2.5.5 Back Office

The back office of the service provider is typically an ICT infrastructure, based on a GEO ICT system or

service. The back office holds the information and allows access to the user mobile device. Location

information and user profiles are typically maintained in the back office, either by service providers or by the

users.

The back office also includes the communication functionality to receive locations from the users and submit

the location based information, based on subscription. In addition, the back office may include the security

infrastructure, customer relations applications, invoicing system, and possibly web portals for users to

configure their services.

2.6 Value chain for GNSS based applications and services

2.6.1 Value chain

Figure 2-11 presents a typical value chain in the provision of GNSS based applications and services, and

introduces a first overview of their business model. Two streams can be identified:

• The realisation of the necessary infrastructure to provide GNSS based applications and services or

“products”. This provision includes the development of the platform, e.g. the receiver terminal and

back office, usually the products which are independent of the actual service.

• The realisation, provision and maintenance of the actual services or “services”, which are the service

specific element, e.g. content, communication and the actual service provider.

Figure 2-11: Overview of the Value Chain for GNSS based applications and services




EC.231207-LOG-A-001 / 1.0 page 39 of 58

The following product provision value chain players can be identified:

• U-Blox, Motorola are examples of companies developing GNSS chipsets, organisations like NXP will

develop these chipsets into e.g. microcontroller stacks for mobile phones and car systems.

• These stacks are used by Garmin, Mio, TomTom, Navigon, Magellan etc. to develop the navigation

systems, and Nokia, HTC, SonyEricsson, Apple (iPhone) etc. for development of GNSS enabled

smart phones.

• For some of the platforms, additional technologies will be added to improve the performance. For

example for car platforms, inertial platform and mapmatching is included.

• For the back office, more traditional ICT solutions, manufacturers and service providers are available.

One of the most recent technologies for LBS is LAYAR (layar.com), for augmented reality. With the

increase of services to be provided to a mobile phone, cloud computing is a technology under

consideration to solve the challenges for channelling of many information resources.

For the service provision, the following players can be identified in the value chain:

• Map developers, of which TeleAtlas (owned by TomTom) and Navteq (owned by Nokia) are well

known. AND is a still independent map supplier, and many open source initiative like Open

Streetmap allow for tailoring the maps to specific needs. GEO solutions will be used to link the map

to specific service information.

• For communication means, the alternative technologies as presented in section 2.5.4 are available.

For use of cellular networks, local communication providers are available.

• For service providers, the list is very long, and depending on the type of service provided. In the

examples section, some of the possible services are identified.

2.6.2 Business Model

It is very challenging to provide a single reference business model, as factors vary between GNSS services.

For illustration purposes, Figure 2-12 introduces a possible service from the Tallinn tourist information office.

On a smart phone (PDA), either your own or rented from the tourist office, a user will obtain tourist

information based on his/her position. For this, a tourist can subscribe to this service for a selected period

and pay the tourist office for this service. As such, the tourist office will generate revenue from the service.

The operator of the cellular network will generate revenue from the data traffic to and from the smart

phone. This can be seen as independent, or the tourist office can prepare a contractual arrangement with

preferred operators. Once the tourist office has an infrastructure in place, it can contact shops, restaurants,

accommodation, and offer the service to provide information to the tourist based on time and location, e.g.

special offerings, marketing messages. By charging these businesses, the tourist office may decide to

reduce charges to the tourist.

Charging either the tourist of the advertising entities can be on different business models as identified in

Figure 2-12. This is an example. Many other business models are possible, even in this specific case.




EC.231207-LOG-A-001 / 1.0 page 40 of 58

Figure 2-12: An example of a business model for a GNSS enabled service

2.7 Examples of Applications

2.7.1 Route-Navigation

Route-Navigation is a well known application of satellite navigation systems. More and more people around

the world use it to navigate to their desired location. It is used in cars, airplanes, and ships. Personal

navigation devices such as hand-held GPS systems are used by mountain climbers and hikers.

The more expensive automobile navigation systems use data from sensors attached to the drive train and a

gyroscope for greater reliability as GPS signal loss and/or multi-path errors can occur due to urban canyons

or tunnels. This augmentation of sensor information in navigations devices is called Dead Reckoning. There

are numerous examples of Route-Navigation systems, such as TomTom, Navman, etc.

GPS Navigation also has applications in the fishing sector, an example of which

is illustrated opposite. The location is used with background maps, which

include navigation aids and wrecks and obstructions in coastal and Great Lakes

waters. Eagle Electronics combines sonar-instruments and GPS-navigation

systems.

2.7.2 Tracking and Tracing

In the technique of tracking and tracing a vehicle, person or asset the receiver determines its position on a

regular basis, which is transmitted via a connection with a back office. The data is processed or monitored

by the back office. Location business rules can be added to the monitoring system to give an alarm

notification when the receiver enters a restricted area. This principle is called Geo-fencing.




EC.231207-LOG-A-001 / 1.0 page 41 of 58

Some example applications using this technique are:

• Tracking and tracing the transport of hazardous materials: The transport vehicles are equipped with

a tracking device, which determines its position and communicates this position to a monitoring back

office. The following figure shows an example of the system architecture.

Figure 2-13: System architecture for tracking & tracing [Source: ARMAS III]

• Recovery of stolen valuable assets: Position of stolen property can be recovered by simply calling the

tracing device, which returns its position to the owner. Car insurance companies already obligate the

use of this technique for expensive cars.

• Fleet management: All transport businesses can have extreme logistic advantages if the company

knows where its vehicles are.

• Tracking and monitoring delinquents on leave.

2.7.3 Surveying

Surveying is the technique and science of accurately

determining the terrestrial or three-dimensional space position

of points and the distances and angles between them. These

points are usually, but not exclusively, associated with positions

on the surface of the Earth, and are often used to establish land

maps and boundaries for ownership or governmental purposes.

In land survey the RTK technique is used to achieve centimetre

accuracy.

Some example applications of surveying are:

• Cadastral surveys: map ownership boundaries for purposes of land valuation and taxation.

• Building and construction measurement




EC.231207-LOG-A-001 / 1.0 page 42 of 58

• Mapping and Geographic Information Services-applications (GIS)

2.7.4 Location Based Services

Location Based Services (LBS) are services enabling users to request information based on their location.

This information is shown on a personal mobile device, such as a mobile phone.

One example of a location-based service might be to allow the subscriber to find the nearest business of

interest, such as an Italian restaurant. The ability of the restaurant to send an invitation to passing people

has also been mentioned, even though this might be regarded as unsolicited commercial email or

spamming. The latter is only allowed when users subscribe to this service.

These services were launched in the late 1990s, and the development in this area seems to be driven by

technical ability rather than by user need.

2.7.5 Automated/Guided Systems

The farming sector is a business area where the use of navigation systems is increasing. Very precise

navigation techniques are used for preparing, planting, and cultivating fields, which are critical operations

that must be performed within minimal times at the right moment (weather conditions can vary quickly)

and very accurately to maximize the land's productivity.

Factory installed automated steering systems are available on tractors and combine harvesters. Such a

system combined with a DGPS or RTK-GPS receiver creates an autopilot capable of working the land via a

fully automated process.

A recently project called “Future Farming Flevoland” has progressed successfully. The tractors are driven

and manoeuvred automatically, using RTK-GPS with an accuracy of 2 cm in straight lines over the land.

2.7.6 Location based games

The availability of hand-held low-cost GPS receivers (approximately €80) has led to recreational applications

including location based games such as the popular game Geocaching. Geocaching involves using a hand-

held GPS unit to travel to a specific longitude and latitude to search for objects hidden by other geocachers.

This popular activity often includes walking or hiking to natural locations providing family orientated

activities for all ages. Other location based games are played controversially by two or more teams on the

streets of a city, but most of these are still in the stage of research rather than a commercial success.

2.7.7 Precise time reference

Many systems that have to be accurately synchronized use GPS as a source of accurate time. For instance,

GPS can be used as a reference clock for time code generators or NTP clocks. Also, when deploying sensors,

for seismology or other monitoring applications, GPS may be used to provide each recording apparatus with

a precise time source, so that the times of events may be recorded accurately. Communication networks

often rely on this precise timing to synchronize RF generating equipment, network equipment, and

multiplexers.



Satellite Telecomunication

EC.231207-LOG-A-001 / 1.0 page 43 of 58

3 SATELLITE TELECOMUNICATION

3.1 Introduction

The telecommunications segment represents the largest and the most mature downstream segment of the

space sector. It comprises two main components: telecommunications and broadcasting, with an additional

distinction being made between fixed and mobile services. Evolution of digital technologies over the last

years have lead to convergence of the satellite telecommunications services sector, with growing

requirements in terms of flexibility and bandwidth. The most promising growth applications in satellite

telecommunications are expected to be mobile and fixed broadband internet access, machine to machine

(M2M) applications, emergency and security service applications and multimedia entertainment.

The need for availability of wide-band communication in all remote areas will drive the next generation of

satellite communication networks. Related services, like tele-medicine, remote control and navigation of the

unmanned vehicles etc., are already used for the military purposes. With the growth of economic potential

of developing countries, the need for video-on-demand services will multiply the capacity requirements of

telecommunication satellites in the near future. In Estonia, the wide use and development of terrestrial

infrastructure for communication services has led to high penetration of the IT services, resulting in almost

100 % coverage of mobile and fixed networks. Extensive use of the satellite communication infrastructure is

not foreseen in the near future except in the field of direct-to-home television broadcasting, which is a

moderately priced and high-quality service, competitive mostly in the rural areas of Estonia (Towards an

Estonian space policy & strategy, July 2008, p. 29).

3.2 Satellite Communications Network and its Functioning

Whist there are many variations depending on the service being provided and the chosen type of satellite

system, the majority of satellite communications adopt the basic architecture shown in Figure 3-1 below.

The following elements are depicted in the figure:

• Satellite: A single satellite or constellation of satellites receiving radio signals from satellite terminals

on the ground and retransmitting them back down to receiving ground terminals. Most importantly

the vast majority of satellite payloads are transparent, i.e. the radio signals transmitted by the

satellite are essentially the same as those received (apart from being amplified and translated in

frequency): this ensures that, once launched, the satellite is flexible to changing service

requirements and technology advances on the ground. Satellites also provide a number of beams for

connecting different coverage areas on the earth, and means for switching channel capacity between

beams. Satellite operators own and generally operate the satellites, through a satellite control or

operations centre (SCC / SOC – responsible for satellite station keeping and monitoring).

The majority of satellite operators still wholesale most of their satellite capacity to a network of

satellite service providers, who then sell the services onto consumers or business / governmental

customers. This situation is changing however, with operators extending their reach in the value




EC.231207-LOG-A-001 / 1.0 page 44 of 58

chain towards the end customers, or service providers starting to procure and operate their own

satellites.

Satellite Control

Centre (SCC)

Satellite Control

Centre (SCC)

Satellite

Ground Network

Private terrestrial

networksNetwork

Gateways Ground

Stations

Satellite Operators

Mobile

Applications

Mobile

Applications

Wholesale

Business Systems

Wholesale

Business Systems

Service CentreService Centre

Service Providers

Wholesale / Retail

Business Systems

Wholesale / Retail

Business Systems

ContentContent

ApplicationsApplications

Application and

Content Providers

Retail Business

Systems

Retail Business

Systems

Public terrestrial

networks

Fixed

Applications

Fixed

Applications

Network Control

Centre (NCC)

Network Control

Centre (NCC)

Figure 3-1: Generalised architecture of a satellite communications network

• Satellite terminals: Users of the satellite service can be connected through a wide variety of

terminals, for instance handheld, vehicle-mounted, airborne, shipborne or fixed installations. The

satellite terminals may themselves provide a gateway to local networks (home or office LAN, campus

networks, local wireless networks) supporting multiple users through a single terminal installation.

• Ground stations: The majority of satellite communications links are established between large

ground stations and the satellite terminals, either as a one-way broadcast network or a hubbed

network providing two-way communications. The ground stations are either owned by the satellite

operator on behalf of their service provider community, or owned and operated by the service

provider directly. Interconnection is made through a satellite ground network and network gateways

into external terrestrial networks (for example public and private telephone networks, the internet,

corporate VPN, governmental networks). Management of the satellite network and ground network

is undertaken by a network control or operations centre (NCC / NOC) by the operator or service

provider; the gateways can be under separate control of the service provider.

The ground station controls allocation of network resources depending on type of service and

satellite terminal demand. In some instances the satellite connection and bandwidth allocation is

fixed (e.g. long-term lease arrangement), in others bandwidth is dynamically allocated and charged

according to the traffic demand (i.e. per voice call or per unit data).

• Service Centre: Some service providers do little more than just connect end users into external

public and/or private networks: in this model, users have a direct relationship with the external

application and content providers (e.g. consumer services over the web, or business applications on




EC.231207-LOG-A-001 / 1.0 page 45 of 58

the corporate network), and the satellite service provider acts merely as a ‘bit pipe’ for access to

these services. For other service providers, for example satellite TV companies, their business

concerns the delivery of complete services to end users: in this case the service provider will operate

the necessary platforms, applications etc to deliver the service (e.g. TV playout facilities) and retail

business systems to manage the relationship with the end customers (billing, customer care etc).

Some service providers do both, i.e. provide access services but also support value-add services,

applications and content through a service centre. VoIP, messaging / email services, broadcast /

multicast content delivery are examples of these. Specialist applications are normally within the end

user community domain.

The satellites themselves can operate in a variety of orbits depending on the regions of the earth to be

covered and the specific requirements of services and applications using the satellite connection. The two

most common, Geostationary Earth Orbit (GEO) and Low Earth Orbit (LEO), are depicted below.

Low Earth Orbit (LEO)• 500 – 1400km altitude• Period ~100 mins• Range of inclinations

(polar orbit shown)

Geostationary Earth Orbit (GEO)• 36000km altitude• Period 24 hours• Equatorial plane(inclined orbits sometimes used)

Figure 3-2: Satellite orbits predominantly used

A comparison of LEO and GEO systems is provided in Table 3-1. Because of their relative network simplicity,

GEO systems (e.g. operated by SES, Intelsat, Eutelsat and Telesat) support by far the most satellite

communications traffic, carrying the vast majority of the world’s satellite TV services and communications to

and from fixed satellite terminals. GEO systems also support mobile applications (e.g. Inmarsat), but this is

also an area where LEO-based systems have captured some of the market for both handheld and low rate

data SCADA applications (e.g. Iridium, Globalstar, Orbcomm).




EC.231207-LOG-A-001 / 1.0 page 46 of 58

GEO LEO

• Appears stationary in the sky

• Ground stations do not need

to track

• 3 satellites can cover the

earth (120° apart)

• Relatively high latency (240-

270ms, ground-space-

ground)

• Polar regions cannot be seen

• Satellite travels across sky from horizon to horizon in 5 -

15 minutes => handoff between satellites may be

required

• Earth stations must track satellite or have omnidirectional

antennas

• Large constellation of satellites is needed for continuous

communication

• Requires complex architecture

• Relatively low latency (~10ms) but currently only supports

low data rates

Table 3-1: Comparison of GEO and LEO systems

Satellite communications services are also classified into Mobile Satellite Services (MSS) and Fixed

Satellite Services (FSS), which principally governs the radio frequency bands that the satellite terminals

use but also broadly describes the types of user and how the satellite communications service is used. (Note

however there are fixed satellite services that are used to support connectivity to vehicles, ships and

aircraft.)

The range of frequency bands used by satellite communications systems and examples of the types of

terminals used within each frequency band are shown below.

VHF/UHF L-band

~1.5GHz

S-band

~2GHz

C-band

~6GHz up~4GHz dn

X-band

~8GHz up~7GHz dn

Ku-band

~14GHz up~10-12GHz dn

Ka-band

~30GHz up~20GHz dn

Mobile Satellite Services (MSS) Fixed Satellite Services (FSS)

Commercial

Military

Commercial Commercial Commercial

Military

Commercial Commercial

sub 1GHz

Figure 3-3: Principal satellite frequency bands and example satellite terminal types




EC.231207-LOG-A-001 / 1.0 page 47 of 58

3.3 Advantages of Satellite Communication

There is a strong and established market for satellite services, generating an estimated €54bn worldwide in

2005 (not including satellite terminal supply). Satellite has positioned itself as a competitive (and sometimes

only) means for providing communications in a number of key market sectors, most obviously TV

broadcasting, but also maritime, aeronautical, media, military and multinational corporate applications. The

costs of launching and operating a satellite system can compare favourably with terrestrial equivalents,

especially in cases where significant new terrestrial infrastructure needs to be rolled out.

The following are the key advantages that satellite communications provides:

• Wide coverage: The most obvious advantage of satellite communications is the ability to cover

large areas with minimal infrastructure roll-out. This enables communications to be provided in areas

difficult or impossible to reach effectively by terrestrial means (maritime, aeronautical and remote

land applications), and also means a single system can be used internationally without incurring

roaming charges, or problems due to system incompatibility or drop outs in terrestrial coverage

(important for example in road transportation, and international emergency applications).

Satellite has to date been used predominantly as an independent service, but the increasing

availability of dual-mode or even multi-mode terminals (i.e. able to connect to both satellite and a

range of terrestrial services, e.g. 3G, WiFi, WiMax etc) opens a range of new opportunities where

satellite augments and extends terrestrial network coverage rather than competes with it. Here the

coverage advantages of satellite are readily evident, with satellite services providing connectivity in

areas where it would be expensive to roll-out adequate terrestrial infrastructure. Significant advances

in the data rates supportable to satellite handheld terminals helps ensure that the user experience is

comparable whether connected via satellite or terrestrial means.

• Broadcast capability: Coupled with its ability to cover large areas is satellite’s natural advantage in

being able to broadcast services to large numbers of users in a bandwidth efficient and hence

extremely cost effective way. This is most evident in the success of analogue and digital satellite TV

services, with significant market penetration in a number of countries worldwide.

An area currently underexploited is the ability of satellite to broadcast content other than live TV or

radio, for example digital files containing films, music, videos or games in consumer markets or

application-specific content (e.g. product information, stock information, weather charts) in business

and governmental markets, potentially taking advantage of quiet periods on the satellite network.

The broadcasted content can be stored and accessed locally whenever the user(s) wish to use it,

either directly or sideloaded into another device (e.g. laptop, mobile phone, portable media players,

portable gaming devices). IP multicasting is key network enabling technology for delivery such

content over satellite broadcast systems.

• Flexibility: As mentioned earlier the transparent nature of most satellite communications systems

means that the satellite infrastructure itself does not need to change if there are changes to the mix

of services provided or upgrades to the radio network. This ensures a good level of future proofing,

allowing the ground stations and terminals to take advantage of technology advances and providing




EC.231207-LOG-A-001 / 1.0 page 48 of 58

the satellite operator or service provider flexibility to introduce new services (within the capability of

the satellite itself). Naturally, successive generations of satellites themselves provide a step change

in the overall capacity provided.

Modern satellite payloads also provide significant flexibility in how the satellite capacity (in terms of

available RF power and bandwidth) is utilised, allowing resources to be utilised according to current

user demands in different parts of the world. This is a key advantage for applications requiring

capacity to be provided on a short-term or potentially longer-term basis in particular parts of the

world (disaster relief, military operations), but also allows satellite operators to optimise resources

according to daily variations in usage.

• Network independence: Satellite communications can provide a vital role in providing connectivity

In situations where terrestrial connectivity is compromised or overloaded, e.g. following natural

disasters (e.g. the 2004 Indian Ocean tsunami) or terrorist activity (e.g. the 9/11 attacks). The near

complete independence of satellite networks from local communications infrastructure is a strong

driver for adoption by disaster relief organisations (e.g. UN, ICRC/IFRC) and by the military and

other governmental organisations. The UN cites satellite as essential in being able to quickly deploy

aid workers anywhere in the world.

Satellite networks also are seeing an increasing role in providing back up communications capability

for corporate and governmental applications, enabling business continuity when the primary

terrestrial network fails. The independence of satellite from local terrestrial infrastructure is again a

key advantage: satellite service offerings are now becoming available to allow this back up facility to

be procured at low cost and enable seamless switching between satellite and terrestrial links in event

of failure.

3.4 Major Service Categories and Promising Applications

The figure below shows the breakdown in revenues from satellite services according to market sector and

application:

SATELLITE

NETWORKS

3B€

Corp.

Networks

1.55B€

Rural

Com.

0.21B€

Defense &

Security

1.23B€

Teleme-

decine

na

CONSUMER

BROADBAND

Internet

direct access

0.2B€

0.16B€

VIDEO

CONTRIBUTION

2.2B€

Sat. news

gathering

0.62B€

Content

Mgt

1.58B€

MOBILE

COMS

1B€

Pro. coms

1B€

Asset

tracking

na

MOBILE

ENTERTAINMENT

0.8B€

DAB

DMB

0.8B€

In-flight

na

VIDEO

DISTRIBUTION

47B€

DTH TV

46.3B€

Digital

Cinema

0.01B€

HITS

0.78B€

Tele-

education

na

Business

TV

na

SATELLITE

NETWORKS

3B€

Corp.

Networks

1.55B€

Rural

Com.

0.21B€

Defense &

Security

1.23B€

Teleme-

decine

na

SATELLITE

NETWORKS

3B€

Corp.

Networks

1.55B€

Rural

Com.

0.21B€

Defense &

Security

1.23B€

Teleme-

decine

na

CONSUMER

BROADBAND

Internet

direct access

0.2B€

0.16B€

CONSUMER

BROADBAND

Internet

direct access

0.2B€

0.16B€

VIDEO

CONTRIBUTION

2.2B€

Sat. news

gathering

0.62B€

Content

Mgt

1.58B€

VIDEO

CONTRIBUTION

2.2B€

Sat. news

gathering

0.62B€

Content

Mgt

1.58B€

MOBILE

COMS

1B€

Pro. coms

1B€

Asset

tracking

na

MOBILE

COMS

1B€

Pro. coms

1B€

Asset

tracking

na

MOBILE

ENTERTAINMENT

0.8B€

DAB

DMB

0.8B€

In-flight

na

MOBILE

ENTERTAINMENT

0.8B€

DAB

DMB

0.8B€

In-flight

na

VIDEO

DISTRIBUTION

47B€

DTH TV

46.3B€

Digital

Cinema

0.01B€

HITS

0.78B€

Tele-

education

na

Business

TV

na

VIDEO

DISTRIBUTION

47B€

DTH TV

46.3B€

Digital

Cinema

0.01B€

HITS

0.78B€

Tele-

education

na

Business

TV

na

Figure 3-4: Satellite service revenues by market sector and application (2005)




EC.231207-LOG-A-001 / 1.0 page 49 of 58

These applications are described below, broken down into the FSS and MSS marketplaces.

3.4.1 Current FSS Services and Applications

The Fixed Satellite Service is dominated by four players, which account for 80% of the revenue generated

by satellite operators in this market. These satellite operators provide a very similar mix of services,

covering media, broadband access and internet backbone services, enterprise / governmental services and

transportation applications, as shown below.

Company Fleet Service offerings Revenue

SES Global

(Luxembourg)

40 DTH, cable head-end, HDTV, iTV, SNG

Home satellite broadband access

IP backbone

Enterprise IP, VSAT

Cellular Backhaul

Mobile broadband (maritime, train)

Governmental services

€1.6 bn

(2007)

Intelsat

(Bermuda/

US)

56 DTH, cable head-end, HDTV, SNG, IPTV

IP backbone

Enterprise IP, VSAT

Cellular Backhaul

Mobile broadband (maritime)


$2.2 bn

(2007)

Eutelsat

(France)

26 DTH, Cable / DTT head-ends, HDTV, iTV, IPTV, SNG,

Business TV

Home / business satellite broadband access

IP backbone

Enterprise IP, VSAT

Cellular Backhaul

Mobile broadband (Euteltracs, maritime, train, business jet)


€877m

(FY 2007-

2008)

TeleSat

(Canada)

13 DTH, Cable / DTT head-ends, HDTV, SNG, Business TV

Home / business satellite broadband access

IP backbone

Enterprise IP, VSAT

Mobile broadband


$653m

(2007)

incl Loral

Skynet

Table 3-2: Service offering of the major players providing a Fixed Satellite Service

As can be readily seen from Figure 3-4 the market is dominated by Direct to Home (DTH) TV Services, a

position which is unlikely to change in the near term, with roll-out of satellite HDTV services already




EC.231207-LOG-A-001 / 1.0 page 50 of 58

underway and expectation of the first 3DTV services by 2012. The largest player in Europe (third in the

world) is Sky (UK) – revenues ~£9M – with CanalSat (France), Sky Italia and Direct+ (Spain) also strong

players, all enjoying a virtual monopoly on satellite TV services in each of their respective countries.

Media in a broader sense also accounts for a considerable portion of remaining FSS revenues with satellite

providing Satellite News Gathering (SNG) backhaul and other video contribution services; supporting cable

TV / DTT head-ends (including so-called “head end in the sky” - HITS – services, where a single satellite

supports a multiplex of TV channels from different providers); and distributing digital cinema and business

TV services.

The other most successful sector is that of VSAT services providing broadband connectivity for businesses

and government organisations, typically through 1-2m diameter dishes. Depending on customer’s utilisation

of the system, VSAT networks can provide fixed bandwidth serial communications (usually on lease

arrangement) or increasingly on-demand IP-based services, where users can be charged by data volume.

In many cases, VSAT is deployed as the primary communications network, but there is also an increasing

trend for VSAT to be used as a back up system which is only pressed into action when terrestrial

connectivity is cut or heavily congested. The near independence of satellites from the local terrestrial

infrastructure makes this an attractive option for business continuity. A potential large future market for

VSAT services also lies in home broadband services – this is covered in greater detail in section 3.4.3 .

FSS services also have reasonable penetration in transportation applications, competing head-on with MSS

providers in these markets. Vehicle tracking systems such as OmniTRACS and EutelTRACS have been

successful in providing low-rate messaged based services to long-distance road haulage and container

fleets, supplying over 500,000 units worldwide. VSAT systems are also showing increased adoption in

maritime applications, especially ocean going container vessels and passenger ships; to a lesser extent

VSAT is also finding application on trains (to support local WiFi hotspots for passengers) and emergency

services communications.

3.4.2 Current MSS Services and Applications

Commercial MSS operators split into two predominant categories: those supporting mobile broadcast

services (TV and radio) to personal and vehicle devices, and those supporting two-way mobile

communications services to a variety of mobile platforms, including handheld, in-vehicle, maritime and

aeronautical.

The leading MSS operators in this sector are shown in the table below.




EC.231207-LOG-A-001 / 1.0 page 51 of 58

Operator Based Satellite

orbit

Principal market

sectors

Coverage Services

Inmarsat UK GEO Maritime, Aero,

Land mobile,

SCADA

Near global Voice, ISDN,

SMS, IP data,

messaging

Thuraya UAE GEO Land mobile,

Maritime

Europe, Africa,

Middle East

Voice, SMS, IP

data

Iridium US LEO Land mobile,

Aero, Maritime,

SCADA

Global Voice, Short Data

Service, IP data

Globalstar US LEO Land mobile.

Maritime, SCADA

Near global Voice, SMS, IP

data

Orbcomm US LEO SCADA Global Store and

forward

messaging

Skyterra US GEO Land mobile,

maritime, SCADA

North America Voice, PTT Voice,

SMS

XM Sirius US GEO /

HEO

Satellite Radio North America In-vehicle radio

and

entertainment

Table 3-3: Major MSS operators and services

The principal market sectors and applications currently served are as follows:

• Land users: A variety of mobile satellite terminals are available to support communications in remote

areas to individuals (handheld or portable capability), vehicles and deployed offices. Capabilities are

generally governed by the size of the terminal: handheld communications and small vehicular

terminals are currently limited to voice, SMS and low rate data services (though see future trends);

portable and larger vehicular terminals can support broadband data speeds (currently up to

~500kbps) enabling potentially many users to connect e.g. via Ethernet or WiFi through the same

terminal.

Current usage typically includes voice communications, standard mobile office applications (e.g.

email, web access, corporate intranet access) and low rate data messaging applications including

location reporting (particularly vehicle tracking). Media organisations also use the higher rate

capabilities of portable terminals to upload recorded video and support live video links for news

reporting. The increased need for content uploading and distribution over mobile satellite services is

seen as one of the major drivers for future services (see future trends).

• Maritime: Satellite communications form a critical part of the Global Maritime Distress and Safety

System (GMDSS), supported for example by the Cospas-Sarsat Emergency Position-Indicating Radio




EC.231207-LOG-A-001 / 1.0 page 52 of 58

Beacon (EPIRB) system for search and rescue operations and the Inmarsat-C SafetyNET service

providing two-way ship-shore messaging communications and a broadcast safety information

service. Inmarsat-C also supports the Long Range Identification and Tracking (LRIT) System, for

tracking passenger and cargo vessels on international voyages.

Satellite communications can also provide a key means for non-safety related communications to

the shore, with relatively inexpensive omnidirectional terminals serving smaller vessels and leisure

craft (Iridium, Globalstar, Inmarsat-C), and progressively larger terminals such as the Inmarsat

FleetBroadband range serving ocean-going yachts, passenger vessels and merchant shipping.

Depending on the terminal type a variety of services / applications are supported including voice

communications, real-time chart and weather updates, web / intranet access, email / SMS and

videoconferencing.

Services are also starting to be extended to the crew (to enable voice / SMS / email communication

with friends and family, e.g. through specially installed phones in the crew quarters), and for

passenger ships GSM services through locally installed base stations and internet access. Note that

fixed satellite services are also being used for some of these applications.

• Aeronautical: Satellite communications is an established means for supporting cockpit-ground

communications for air traffic control (ATC) and aeronautical operational control (AOC) services,

through two-way voice and low rate data messaging. Though currently used predominantly in ocean

regions, satellite potentially will be an integral component of the European SESAR programme

aiming to provide a new harmonised Air Traffic Management (ATM) infrastructure for managing

Europe’ airspace by 2020: ESA is funding studies into how satellite should support this vision through

their IRIS programme.

SatComs is also set to play a significant role in enabling new cabin services on passenger aircraft,

notably supporting use of GSM phones for voice, SMS and eventually GPRS data services during the

flight. Regulatory approval has been given in some regions to operate GSM picocells onboard

aircraft, with services already provided by AeroMobile on Emirates and Malaysia airlines, and being

trialled by a number of European airlines through the OnAir service.

• SCADA / M2M applications: Satellite communications also has an established market in supporting

automatic monitoring and control of remote assets, historically described as Supervisory Control and

Data Acquisition (SCADA) applications but increasingly referred to under the more general banner of

machine-to-machine (M2M) applications. Depending on the application, communications here do not

necessarily need to be supported in real-time, enabling store and forward messaging services to be

used as supported by market-specific players (e.g. Orbcomm).

Principals users of M2M services are the transportation and distribution sector (e.g. vehicle and

goods tracking, maritime safety services) as already described, but satellite also has an established

role in remote monitoring and control of high value assets in the oil and gas (oil and gas extraction,

pipelines, storage facilities) and utility industries (power lines, water monitoring). There are however

a wealth of emerging M2M applications driven in particular by the green agenda and homeland




EC.231207-LOG-A-001 / 1.0 page 53 of 58

security concerns all of which could potentially be supported by satellite (see future trends – section

3.4.3 ).

• Media broadcast: Significant media coverage has been given to the use of satellite broadcasting to

support mobile TV and radio services to mobile handsets and in-vehicle entertainment systems.

Whilst there have been some qualified success stories, notably the XM-Sirius satellite radio service in

North America (reaching approximately 20 million), and to a lesser extent the satellite mobile TV

service in South Korea, the business case for widespread mobile TV roll out remains to be proven

whether supported by satellite or terrestrial means. The major hurdle for satellite mobile

broadcasters lies in getting good service availability in towns and cities: an ancillary terrestrial

component (ATC) comprising a network of ground repeaters is required to provide the necessary

reception, significantly increasing the cost of such ventures.

3.4.3 Future trends

Increasingly sophisticated spacecraft with flexible switching of capacity to beams and highly directive

onboard antennas able to form multiple small spot beams on the earth’s surface, have enabled the GEO-

based operators to introduce increasingly capable services to their users. The LEO-based MSS operators

have also announced their next generation of systems which will increase their capabilities.

Of particular interest within the MSS community currently are the new services to be offered by GEO

systems at S-band, with the potential of providing medium-high rate communications to handheld and

vehicle-mounted terminals. Terrastar (US) launched its S-band satellite in 2009, with services expected to

be rolled out in H1 2010. The satellite, one of the largest commercial spacecraft ever launched, will support

500 spot beams covering North America enabling services approaching those of terrestrial 2.5 and 3G

systems (noting that terrestrial repeaters are required for high service availability in cities). Licences for

pan-European S-band spectrum were awarded to Inmarsat and Solaris Mobile also in 2009, with the

requirement to launch by 2011.

With C-band and Ku-band becoming increasingly saturated significant focus is now being placed within the

FSS community on Ka-band systems, operating at 30/20 GHz. Substantial amounts of spectrum are

available making it particular attractive for the TV, business and home broadband market. Technical

challenges in particular the high rain fade experience at these high frequencies have until recently hindered

the move to Ka, but systems are already providing service particularly in North America, with European

service already provided by SES and within 2010 by Eutelsat and Avanti.

The figure below shows what we believe are some of the key growth applications which will be supported

through future MSS and FSS systems.




EC.231207-LOG-A-001 / 1.0 page 54 of 58

Satellite home broadband

Two-way services, 10Mbps+

Broadcast IPTVMedia distribution services

Gaming, entertainment

Emergency & security services

GIS systems, situational awareness

Database checks, image recognitionImage / video upload, CCTV

Medical records / telemedicine

Intelligent Transport Systems

Congestion avoidance

Driver information servicesRoad user charging

Automated accident reporting

Machine to Machine (M2M)

Asset tracking

Remote monitoring andmaintenance

Environmental regulation

High speed data, VoIP,IPTV, IP Multicast

High speed data, Netted voice,Messaging, IP Multicast

High speed data, Messaging,IP Multicast

Low rate data,Messaging

Direct toHome

WiFI

Figure 3-5: Important growth applications and services in satellite communications

We believe the main areas for satcoms growth are in the following:

• Emergency and security service communications: The availability of next

generation mobile satellite services will provide national and international

emergency, civil protection and military organisations with new capabilities

to keep field units better informed on operational progress and improve

overall situational awareness. Satellite will act as an overlay service,

providing a high rate data services capability to complement existing voice services supported by

terrestrial networks such as TETRA, TETRAPOL and P25.

The Terrastar service (US) promises delivery of high rate services to multimode devices (above),

incorporating satcom, 2G, 3G and WiFi into a single PDA-sized device: similar services are projected

to be delivered over Europe in a two-three year timeframe, potentially having TETRA network

connectivity also integrated into the handset. Improvements will also been seen to vehicle-mounted

satcoms giving true broadband two-way communications on the move (COTM) from relatively

small antenna units. Vehicles can then act as wireless relays to allow personnel to connect using

smartphones, PDAs, laptops etc at the scene.

The availability of high rate bidirectional IP data

communications is seen of critical importance to future

emergency and security service operations. In the upstream

direction, this would support uploading of photos, other

images, sensor data, video, CCTV back to the operational

HQ or data processing centre. In the downstream direction,

processed content (e.g. GIS systems showing locations




EC.231207-LOG-A-001 / 1.0 page 55 of 58

and status of operational staff, potentially augmented satellite EO images) would be

disseminated back out to the operational staff. This aids greater situational awareness (right) in the

field and improved operational effectiveness. Allied to this is the increasing need to support one-way

and two-way real-time video communications from the field, for example for telemedicine, remote

monitoring and surveillance applications. Availability of video communications also provides non-

operational benefits in terms of engaging with the media and promoting support from fund-donating

organisations.

• Intelligent transport systems: Satellite is also well positioned to support future transport systems,

with vehicle-mounted terminals enabling a range of private and commercial vehicle applications,

either using satellite only systems or, more likely, using multimode capability as above. Applications

include road user charging, automatic accident reporting, congestion detection and

avoidance, vehicle health and fuel consumption monitoring and driver information

services. The latter is particularly suited to satellite given its ability to cost-effectively broadcast

information over a wide coverage area; indeed a variety of in-vehicle systems could benefit from

data and software updates broadcasted via satellite.

• M2M: The market growth in machine to machine communications (M2M) over the next 5-10 years is

expected to be significant even by the most conservative of estimates, with both government policy

(e.g. environmental monitoring, GHG regulation) and private sector needs (e.g. remote

equipment monitoring and maintenance, asset tracking, automated payment systems)

driving the demand. It is predicted that existing terrestrial networks will be unable to serve the

demand and/or provide sufficient coverage, leading to a number of key new opportunities for

satellite communications either as a standalone network or as a satellite-terrestrial hybrid. Existing

MSS systems are already in a position to target some of these new applications with no new

requirements on infrastructure.

• Satellite broadband: An estimated 70m European homes are currently unable to receive a basic

2Mbps broadband service, creating the so-called “Digital Divide”. Initiatives are underway at a

national (e.g. the Digital Britain programme) and European level (e.g. EU plans to subsidise rural

broadband access by up to €1.8bn).to help bridge this gap and provide universal access to all.

However it is a situation that is likely to reappear and worsen as Next Generation Access (e.g.

through fibre communications) are started to be rolled out – for instance in the UK it is estimated

that only two-thirds of the population will be reached by the NGA market forces alone. Satellite

broadband has significant potential to support both universal access at 2Mbps and, ultimately, NGA

services to rural areas, repeating the success of US satellite broadband services which currently

support over 1 million subscribers. The particular advantages of satcom could be exploited to provide

a range of cost-effective value add services such as broadcast IPTV and mass content distribution.

Costs of terminals and services are also continually reducing in this sector.



Abbreviations

EC.231207-LOG-A-001 / 1.0 page 56 of 58

ABBREVIATIONS

Acronym Definition

AGPS Assisted GPS

DTH Direct to Home

EC European Commission

EEA European Environment Authority

EO Earth Observation

ESA European Space Agency

GBAS Ground Based Augmentation System

GCM GMES Contributory Mission

GEO Geostationary Earth Orbit

GMES Global Monitoring for Environment and Security

GRAS Ground-based Regional Augmentation System

GSCDA GMES Space Component Data Access

HITS “head end in the sky”

INS Inertial Navigation System

LEO Low Earth Orbit

MSS Mobile Satellite Services

FSS Fixed Satellite Services

NAVSTAR GPS Navigation Signal Timing And Ranging GPS

NCC Network Control Centre

NOC Network Operations Centre

RAIM Receiver Autonomous Integrity Monitoring

RTK Real Time Kinematic

SatCom Satellite Communications

SatNav Satellite Navigation

SAR Search and Rescue

SAR Synthetic Aperture Radar

SBAS Satellite Based Augmentation System

SCC Satellite Control Centre

SNG Satellite News Gathering

SOC Satellite Operations Centre

VRS Virtual Reference Station



Glossary

EC.231207-LOG-A-001 / 1.0 page 57 of 58

GLOSSARY

Term Definition

Earth Observation The acquisition and exploitation of data from aerial or satellite-based

observations of the Earth.

Acquisition Collecting data from aerial or satellite-based observations, putting it

into a usable format, and making it accessible to the users of the

data

Exploitation Putting the data to use, e.g. in weather forecasting, flood damage

assessment, or selling posters of famous landmarks seen from space.

Satellite Based

Augmentation System

A system that supports wide-area or regional augmentation through

the use of additional satellite-broadcast messages.

Ground Based

Augmentation System

and Ground-based

Regional Augmentation

System

a system that supports augmentation through the use of terrestrial

radio messages

Differential GPS Can refer to both the general differential technique, as well as

specific implementations of it

Multi-path Radio signals reflect off surrounding terrain; buildings, canyon walls,

hard ground, etc.

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