esa alive initiative
DESCRIPTION
ESA ALIVE Initiative. A Satellite-Based Communication Channel for the Reliable Distribution of Early Warning Messages The Alert Interface via EGNOS (ALIVE) for Disaster Prevention and Mitigation. Presentation Topics. The requirements for an alert system - PowerPoint PPT PresentationTRANSCRIPT
ESA ALIVE Initiative
A Satellite-Based Communication Channel
for the Reliable Distribution of Early Warning Messages
The Alert Interface via EGNOS (ALIVE)
for Disaster Prevention and Mitigation
• The requirements for an alert system
• Overview of SBAS (Satellite Based Augmentation
Systems)
• How SBAS meets the alert requirements
• The ALIVE concept
• Possible implementation strategy
Presentation Topics
The Need for an Alert System
• Disasters are as devastating to advanced nations as they are to third world~• Arguably, we are more reliant on technology
• ‘000’s of lives can be saved by early warning and mitigation
• Disasters do not respect national boundaries
• But one type of communications channel cannot meet the needs of all citizens at all times
High Level Requirements
• Resilient from terrestrial infrastructure damage
• High level of integrity
• Institutionally owned
• End user device must be ubiquitous
• Global standard, integrated into disaster management centres
• Cope with several contemporaneous events
• The requirements for an alert system
• Overview of SBAS (Satellite Based Augmentation
Systems)
• How SBAS meets the alert requirements
• The ALIVE concept
• Possible implementation strategy
Presentation Topics
SBAS – an augmentation to GPS
EGNOS – where we are today
• EGNOS is due to become operational in Mar 08• Technical performance already stable
• Differential corrections for GPS• Upgradeable to other GNSS including Galileo
• 1-2m accuracy from wide area corrections• Equivalent to commercial DGPS services
• Integrity alert within 6 seconds if position information is deemed unreliable
• Free to air at point of end use• Signals received via geostationary satellite in same frequency
band as GPS
Satellite-based Augmentation Systems• Three SBAS Systems:
• USA: Wide Area Augmentation System (WAAS)
• JAPAN: Multifunction Satellite Augmentation System (MSAS)
• EUROPE: European Geostationary Navigation Overlay System (EGNOS)
• Global service interoperability
• Institutionally controlled, secure, operated for safety of life applications
• Designed to:• guarantee adequate message broadcast
• provide integrity of messages
• provide confirmation of transmission
• Receivers are:• based on GPS receivers
• share same globally accepted standards
• are the most abundant “satellite communication receivers” in the world
• Receivers combine capability of receiving messages with the ability to:
• determine the location of the receiver
• the three existing SBAS together provide a global coverage
SBAS Characteristics
• The requirements for an alert system
• Overview of SBAS (Satellite Based Augmentation
Systems)
• How SBAS meets the alert requirements
• The ALIVE concept
• Possible implementation strategy
Presentation Topics
The disaster alert proposal…
• Communication capacity larger than required for system operation - sufficient margin to send additional ALIVE messages
• Inherent characteristics appropriate for alert messages• Ground-based infrastructure is very unlikely to be
affected by a disaster/crisis• SBAS communication channel cannot be disrupted in a
crisis situation (ARNS protected bands)
Unique opportunity for broadcasting of alert messages
How SBAS Meets Alert requirements
• SBAS receivers get alert messages and also have their position simultaneously - only users in target areas need to act
• Unique worldwide standard - all SBAS receivers are identical
• SBAS operated with all guarantees - Safety of Life, Institutional control, 24 hours non stop; confirmation message is broadcast in time
• Can be implemented in very short time• Works in places with no operational infrastructure• Potential global coverage together with all other SBAS
EGNOS Capability
• EGNOS has to respect minimum update rate to comply with safety of life requirements – primary mission.
• Possibly 35% of bandwidth is available• A 250-bit message every 3-4 seconds (75 bps)
• Without SA this increases to 140 bps
• Compares favourably to SAR preliminary mission analysis requirement of 7 bps.
• The requirements for an alert system
• Overview of SBAS (Satellite Based Augmentation
Systems)
• How SBAS meets the alert requirements
• The ALIVE concept
• Possible Implementation Strategy
Presentation Topics
• The architecture of ALIVE implementation….
The Alert Interface Via EGNOS (ALIVE)
• The requirements for an alert system
• Overview of SBAS (Satellite Based Augmentation
Systems)
• How SBAS meets the alert requirements
• The ALIVE concept
• Possible Implementation Strategy
Presentation Topics
Key implementation issues
• Need for global coverage and international co-operation
• Technical feasibility and potential affects on core EGNOS mission
• Receiver compatibility and functionality and implications for device manufacturers
• System architecture definition and requirements for on-board database – thin or thick client?
• Institutional convergence amongst interested governments and agencies
• Development of revised SBAS international standards
• The need for a flexible data interchange format for collecting and distributing early warnings over information networks and the potential adoption of the OASIS CAP standard
Possible Implementation Strategy
Step 1: Presentation of the ALIVE concept to relevant Disaster Management authorities (in progress)
Step 2: Feasibility assessment of SBAS functionality,
Step 3: Consolidation of ALIVE Mission Requirements with
expert groups
Step 4: Propose the SBAS communication functionality (incl. ALIVE) in the context of the GNSS Accompanying Program for ESA delegations consideration
Step 5: Detailed specifications; message standardization; detailed definition study; test services through EGNOS test Bed ; SBAS ALIVE enabled receiver detailed design.
Step 6: SBAS communication function (incl ALIVE mission) Implementation Phase and development of SBAS ALIVE enabled receivers
Step 7: Operational integration of the SBAS comm. functionality (inc ALIVE mission) in EGNOS
Step 8: Disaster prevention/mitigation qualification and start of operations (could start in 2008)
Conclusions
• SBAS cannot be regarded as ‘one stop shop’ for disaster alert broadcast channel
• Must be seen in context of suite of channels designed to meet specific needs of citizens• Commercial satellite communications• Public mobile networks• Public fixed networks• Private mobile data• Terrestrial broadcast (TV, Radio)• Internet/email• Public address
SBAS – an effective, complementary and inexpensive disaster alert broadcast channel
• The three existing SBAS together provide global coverage and share the same worldwide accepted standards
• SBAS GPS combine the possibility of warning with the ability to determine the location of the receiver in the same equipment
• The SBAS systems, having been conceived as safety critical systems with the necessary built-in features to guarantee timeliness of delivery, confirmation of transmission and service availability
• SBAS are institutionally controlled and may readily support the necessary regulated structures to control service access
• SBAS offers a very low operational cost suitable for a public service when compared to most other solutions
• SBAS (like other space systems) offers survivability in the event of many (terrestrial) disasters as well as speedy restoration after the event
