Automatic Person Location Technologies and Solutions for Public Safety Users

Kenneth HubnerInternational Business Development Manager

Sepura Limited

Agenda

• Market Drivers and Solution Influencing Factors

• Command and Control Requirements

• Review of current technologies

• TETRA services used for location solutions

• Future of APLS enabled products for public safety users

Market Drivers

• FCC E911 Mandate in the US– Call centres – Terminal or Network implemented solutions

• 50 - 100 metre accuracy for at least 67% of cases

• 150 - 300 metre accuracy for at least 95% of cases

• EU E112 Mandate in Europe– Still not implemented !

– No defined accuracy specified !

Both systems proposing using either TDOA or GPS

• Many Blue Light Forces now mandating APLS

Market Drivers

Public Safety Benefits

Know where someone is: save LIFE.

Better allocation of resources, prompt reaction to an Emergency: save TIME.

Better Control of the fleet: save MONEY

Solution Influencing Factors

• Price

• Accuracy and coverage

• Ergonomics

• Power consumption

• Can the solution be supported by TETRA ?– Network support and bandwidth requirements

Command & Control Requirements

• Effective management

• Requirements differ from AVLS

• User needs to feel unthreatened by APLS

• Linking of various systems/databases to provide officer with advance warning of possible dangers

Command & Control RequirementsAVLS example

Command & Control RequirementsAPLS example

Command & Control RequirementsAPLS with filtering

Review of Current Technologies

Low accuracy, low cost solutions– Time difference of arrival– Enhanced observed time difference

Medium accuracy, medium cost solutions– Standard GPS– Assisted GPS– Low signal strength GPS

High accuracy, high cost solutions– Differential GPS– Combinations of Solutions

Review of Current Technologies

Low accuracy, low cost solutions

Time Difference Of Arrival (TDOA)– Inexpensive for terminals but can be very costly to implement in the network– accuracy of location is +/- 500 metres

Enhanced Observed Time Difference (EOTD)– low cost, no base station support now claimed– accuracy of location is 200m - 2km

Both technologies – Have good indoor/urban canyon penetration, but with very poor accuracy - a general show stopping issue for network based solutions where location accuracy could be critical

– Are bandwidth hungry therefore not suitable for TETRA

Network Based Solutions - example

LMU

Radio tower

C&CServer

GIS orMapping

Application

GIS orMapping

Application

TETRAGateway

LMU LMU

LMU

Network Based Solutions

Current Accuracy = 200m - 2km

Future Accuracy =100m - 500m

Review of Current Technologies

Medium accuracy, medium cost solutions

Standard GPS

– time to first acquisition (fix) is typically 3 mins

– >30 metres accuracy, no indoors or urban canyon coverage

Assisted GPS

– time to first acquisition is typically 30 secs

– >30 metres accuracy

Low Signal Strength GPS (high sensitivity)

– time to first acquisition is typically 45 secs

– <30 metres accuracy

– indoors/urban canyons

Note, all the above have a location accuracy of <10 metres for 95% of

cases in open space

GPS solutions - examples

Dispatch workstations

Radio tower

PBX

Workstation

MappingApplication

TETRANetwork

Workstation

Workstation

Workstation

Mapping Server

Base station

TETRA gateway

C&C firewall

C & C LAN

SDS

C & C Servers

Review of Current Technologies

High accuracy, high cost solutions

Differential GPS– open space accuracy <10 metres off– expensive to implement with land based differential base stations required and regular network broadcasts

– Network bandwidth hungry

Solution Combinations (GPS+Beacons+Odometer)– accuracy anywhere between 0 - 10 metres– very expensive beacon network required to support this

High accuracy Solutions - examples

Tower boxC&C

Server

GIS orMapping

Application

GIS orMapping

Application

TETRANetwork

TETRAGateway

GPS

dGPS Station

TETRA services used for APLS

Data over network - Size of problem!Typically, position report messages could carry some or all of the

following:

– Date, Time, Latitude, Longitude, Altitude, Speed, Heading, Fix type, Confidence Level, Status, Fix Reason, Terminal ID, User Defined Field.

Amount of message traffic generated by APLS systems is much

larger than for AVLS

– Usage could increase 10 or 100 fold ! – Requires sophisticated filtering at command &control

TETRA services used for APLSTETRA services allow use of SDS messaging for transmission of GPS data:

EN 300 392-2: TETRA (Voice plus Data (V+D), part 2: Air Interface, v2.3.2

SDS4 and SDS-TL delivers variable length messages to 2047 bits(255 bytes)

GPS location data is provided in the NMEA formats, GLL, GSA, GGA etc.

– Typical GLL mesage could contain as much as 48 bytes of data!

– In busy periods, with many location reports being sent, this could cause network overload

Location Information Protocol –TS 100 392-18-1 v1.1.1 Jan 2005

– Specifies the effective use of network by using compact message formats

– Typical message (compared to GLL) is 11 bytes long!

Future of APLS & TETRA Terminals

Technology Influenced Solutions

– Continuing integration of IC’s and components enables space saving in handsets and is an opportunity to integrate location devices like GPS.

– The European Galileo system should be operational by 2008 and this is supposed to perform better than the existing US DoD GPS system.

Clear Sky

Under Foliage

Wooden Building

Urban Canyon

Single Storey Brick Building

Multi Storey Concrete building

Underground?

2002 2003 2004 2005 2006 2007 2008 2010………………………….. 2015 2020 2030

High sensitivity GPS

L1, L2 + L5 Frequency(+ Galileo?)

Galileo

Future GPS ?

Other Sensors – e.g. Gyroscope, Accelerometers

GPS future Trends

High Quality Receiver

High Quality Hand HeldReceiver

Conduct User Trials

Product A

Product B4 times betteraccuracy

and availability

User Trial Essential!

Summary Enhances user safety

- Lone worker + Emergency Button + GPS- Accurate Location

Improves resource usage- Improves response times- Selection of most appropriate resource- Reduce wasted resource

Improves reporting accuracy- Knowing precisely where an incident took place

High sensitive GPS receivers are available in TETRAterminals today.

Make GPS mandatory in your handsets today

Thank You!

kenneth.hubner@sepura.com