Transcript 09 Space Based Augmentation Systems

Global Navigation Satellite Systems
Space Based Augmentation Systems
Copyright 2006 EUROCONTROL
1
Agenda

Space Based Augmentation Systems Principles

Implementations: EGNOS

Implementations: USA's WAAS

Implementations: Japan's MSAS
Copyright 2006 EUROCONTROL
2
SBAS: The Principle
True Location
Indicated Location
Satellite Broadcast of:
1. Vector Correction
2. ‘Use/Don’t Use’
3. Ranging Signal
Atmospheric
Effects
Single Frequency
Avionics
(x,y,z)
(x,y,z)
(x,y,z)
Reference Stations (RSs)
Dual or Single Frequency
NAV32516.3602
Master Control Site
(MCS)
Copyright 2006 EUROCONTROL
3
Typical SBAS Requirements
Lateral
Vertical
Accuracy Accuracy
95%
95%
Integrity
(2)
Time to
Alert (3)
Continuity
Availability
(4)
(5)
5 min
1-10 /h to
(1)(3)
En-Route
2 NM (6)
N/A
-7
1-10 /h
-4
-8
1-10 /h
-7
ER, Terminal
0.4 NM
N/A
1-10 /h
15 s
-4
1-10 /h to
-8
1-10 /h
Initial and
Intermediate
Approach,
NPA, SID
APV-I
-7
220 m
N/A
1-10 /h
10 s
-4
1-10 /h to
-8
1-10 /h
16.0 m
APV-II
16.0 m
PA- CATI (8)
16.0 m
20 m
-7
1-2x10 /h
per
approach
-7
8.0 m
1-2x10 /h
per
approach
6.0 m to 1-2x10-7/h
per
4.0 m (7)
approach
-6
10 s
1-8x10 in
any 15 s
6s
1-8x10 in
any 15 s
6s
1-8x10 in
any 15 s
Copyright 2006 EUROCONTROL
-6
-6
0.99 to
0.99999
0.99 to
0.99999
0.99 to
0.99999
0.99 to
0.99999
0.99 to
0.99999
0.99 to
0.99999
4
Overview of SBAS Objectives

Augment GPS & Possibly GLONASS

Achieve Aviation Requirements With Added
– Integrity - monitoring and “use/don’t use” message
– Accuracy - with differential corrections
– Availability & Continuity - with ranging signals

Serve En-route Down to Category I Precision
Approach

Time Scales: Introduction beginning 2006+
Copyright 2006 EUROCONTROL
5
The Role of the Geostationary Satellite
Geostationary satellite
Uplink Corrections
Repeat,
Broadcast
Corrections
Copyright 2006 EUROCONTROL
6
GEOS Satellites in Service: Examples

INMARSAT-III
– POR
– IOR
– AOR-W
– AOR-E

ARTEMIS
– Launch Failed
– Eventually reached correct orbit end of Jan 03
Copyright 2006 EUROCONTROL
7
INMARSAT III AND ARTEMIS Broadcast Areas
AOR-W
AOR-E
ARTEMIS
IOR
POR
POR
Copyright 2006 EUROCONTROL
8
Three Interwoven Services (1)

Ranging
– the geostationary satellite(s) broadcasts a spreadspectrum ranging signal
– avionics adds this “GPS-like” signal to the existing set of
GPS measurements
– improves availability and continuity

Integrity
– supporting ground network monitors the health of all SVs
– “use/don’t use” warnings broadcast via geostationary
satellite(s)
– improves flight safety
Copyright 2006 EUROCONTROL
9
Three Interwoven Services (2)

Accuracy
– ground network also develops differential corrections
for all SVs
– broadcast via geostationary satellites (along with
integrity data)
– separate corrections for SV clock, SV ephemeris &
ionosphere
– such a vector correction is valid over continental areas
– improves accuracy from 100 meters to better than 8
meters
Copyright 2006 EUROCONTROL
10
Vertical Ionospheric Delay (m)
Ionospheric Measurements: MCS Outputs
Local Time: 13:17:60
5
4
3
2
1
0
55
50
Arcata
45
Elko
San Diego
Stanford
-105
-110
-115
35
-120
30
-125
Latitude (deg) 25
-130
Longitude (deg)
-135
20
-140
40
Vertical Ionospheric Delay Estimated at Stanford University
(West Coast Region of United States)
Copyright 2006 EUROCONTROL
11
GEO Navigation Signal Characteristics

Frequency:
1575.42 MHz

Modulation:
BPSK

PRN code:
1023 bit Gold codes with good
orthogonality to GPS codes

Data rate:
250 bit per second (encoded with
forward error correction to 500 bps
throughput)

Polarisation:
Right handed circular
Copyright 2006 EUROCONTROL
12
SBAS Messages Types
Type Contents
0
1
2-5
6
7
9
10
12
17
18
24
25
26
27
63
Others
GEO information useless (SBAS test mode)
PRN Mask
Fast corrections
Integrity information
Fast corrections degradation factor
GEO ranging functions parameters
Degradation parameters
SBAS Network Time/UTC offset parameters
GEO satellite almanacs
Ionospheric grid point masks
Mixed fast corrections/long term satellite error corrections
Long term satellite error corrections
Ionospheric delay corrections
SBAS service message
Null Message
Reserved
Copyright 2006 EUROCONTROL
13
Global Navigation Satellite Systems
Space Based Augmentation Systems
Copyright 2006 EUROCONTROL
15
Problems at High Latitudes

Concern about the visibility of geostationary satellites at
the edge of the coverage footprints

Reception may be particularly difficult during aircraft
maneuvers

Reception is particularly critical during approach &
landing

Eurocontrol organized flight trials:
– to investigate reception at high latitudes
– real flight data rather than simulation
– designed flight trials with UK CAA and DRA Bedford
– October 1994: trials conducted with DRA’s BAC-1-11
Copyright 2006 EUROCONTROL
16
High Altitudes: Flight Trial Route
Svalbard
Thule
Tromso
Sondrestrom
Keflavik
Bergen
Trondheim
Stockholm
Boscombe
Down
Copyright 2006 EUROCONTROL
17
Agenda

Space Based Augmentation Systems Principles

Implementations: EGNOS

Implementations: USA's WAAS

Implementations: Japan's MSAS
Copyright 2006 EUROCONTROL
18
What is EGNOS?

European implementation of SBAS

Operating using INMARSAT GEOs and ESA
ARTEMIS

Aimed to provide:
– Integrity
– Continuity
– Accuracy
– Availability

Use with GPS and GLONASS

Planned to be compatible WAAS, MSAS and
GAGAN
Copyright 2006 EUROCONTROL
19
EGNOS Milestones
96
AOC INITIAL PHASE:
Baseline System Design
Early Trials
97
98
99
00
01
02
03
04
05
06
MRR BSDR
PDR
Preliminary System Design
TEST BED:
Development & Integration
Verification
Operation
AOC IMPLEMENTATION:
PDR
System Development
CDR
FQR
ORR
Deployment & Verification
Initial Operations
Copyright 2006 EUROCONTROL
20
EGNOS Timescale: Initial Operations
2006
2007
ORR
ODR
OQR
Operations
performance
Ramp-up
Stabilization
Qualification
ESA Reqt
Δ ESA Reqt
Δ ESA Reqt
+3
+6
+9
+12
+15
Time (in months)
Copyright 2006 EUROCONTROL
21
EGNOS: Service Area
Geostationary
Broadcast Area
Corrections for Accuracy
Ranging for Availability
Continuity and Integrity for Flight Safety
Copyright 2006 EUROCONTROL
22
EGNOS AOC Phase

Advanced Operational Capability (AOC)
– Ranging function
– Ground Integrity function
– Wide Area Differential function
– Operations down to APV II
– 2006 onwards

System consists of:
– Space Segment
– Ground Segment
Copyright 2006 EUROCONTROL
23
EGNOS FOC

Final Operational Capability (FOC)
– No longer considered
– Did not provide additional functionality
– Additional system components to increase
availability and continuity performance
– Sole means (Volpe Report) of operation, down
to CAT-I precision approach
– Originally planned 2 years after AOC
Copyright 2006 EUROCONTROL
24
European Tripartite Agreement
Development - Deployment - Technical Validation.
Institutional and policy matters, the coordination of
the implementation of a Transeuropean navigation
and positioning network, identification of user
requirements. Funding the navigation transponders.
Mission requirements for civil aviation,
operational test and validation for aviation,
support for safety regulation.
Copyright 2006 EUROCONTROL
25
Participating States
Copyright 2006 EUROCONTROL
26
Financing EGNOS to Operational Use
EC
EOIG
ESA

Total cost to Operational Readiness Review (Apr 04):
– € 310 Million

Annual running costs:
– € 33 Million (15% of GALILEO’s costs)

Approval Procedure costs and additional expenses:
– € 14.4 Million
NAV32516.3627
Copyright 2006 EUROCONTROL
27
Advantages of EGNOS
General:
– Technical
 Enabled Europe to develop capability and know how
 Enhance GPS and GLONASS services
 Will be provided free (at outset!)
 Will provide some guarantees
– Political
 Completes first phase of European GNSS
 Offers opportunities in developing countries with
poor infrastructure
 A product of US, Russian and EU cooperation
 Sectors
– Civil aviation has the most demanding requirements
NAV32516.3628

Copyright 2006 EUROCONTROL
28
EGNOS Expected Performance

GEOs provide 3 additional ranging sources

3 satellites to fix position in 2 dimensions
– +/- 3 metres expected

4 satellites to fix position in 3 dimensions
– +/- 5 metres expected

Significant improvement in integrity expected
– Probability of SBAS not detecting a failure is 10-7
– RAIM will used to protect against local effects
Copyright 2006 EUROCONTROL
29
EGNOS: System Design
Geostationary
Satellites
GPS
Navigation
Reference
Signal
(C-band)
NLES
•Transmits navigation
and integrity data
GLONASS
Navigation
Signals
(L-band)
Master Control Centre
•Generates NAV signal
•Processes integrity
information
•Provides WADGNSS
corrections
Copyright 2006 EUROCONTROL
Wide Area Ground Segment
•Provides monitoring network
•Checks integrity
•Collects GPS/GLONASS/GEO
data
30
EGNOS: Ground Segment (1)
RIMS
(x 34)
NLES
(x 6)
EWAN
MCC 1
MCC 2
MCC 3
MCC 4
Copyright 2006 EUROCONTROL
PACF
ASQF
DVP
31
EGNOS: Ground Segment (2)
MCC
RIMS
NLES
Copyright 2006 EUROCONTROL
32
EGNOS Representative RIMS Locations
Copyright 2006 EUROCONTROL
33
EGNOS: Master Control Centres (MCC)

MCC: Master Control Centres
– Spain, UK, Germany and Italy
– Pre-planned rotation of MCC

Comprised of 2 parts:
– CPF
– CCF

Functions
– Determine the integrity
– Determine Pseudo Range differential corrections
for each monitored satellite
– Determine ionospheric delay
– Generate GEO satellite ephemeris
Copyright 2006 EUROCONTROL
34
EGNOS: Ranging and Integrity Monitor
Stations (RIMS)

33 RIMS:
– Type A - Raw measurements of GPS,GLONASS,GEO
for CPF processing
– Type B - Raw measurements of GPS,GLONASS,GEO
for CPF checking
– Type C (15 only) - Evil waveforms - GPS only

Paris RIM (Type A)
– Measure difference between UTC and EGNOS
Network Time

Functions
– Data collection
– Transmit data to all MCCs every second
Copyright 2006 EUROCONTROL
35
EGNOS: Navigation Land Earth stations
(NLES)


NLES: Navigation Land Earth Station
Functions
– Select the message provider CPF
– Modulate the message generated by the CPF
– Synchronise the up-link signal to GPS time
– Up-link data
AOR-E
Artemis
Copyright 2006 EUROCONTROL
IOR-W
36
EGNOS Wide Area Network (EWAN)
RIMS
SubNetwork
NLES-1
NLES-6
MCC3
MCC2
Back-Bone
2 Mbps
NLES-1
MCC4
MCC1
Copyright 2006 EUROCONTROL
37
EGNOS Support Facilities: ESTB
Tromsö (N)
EURIDIS RS
Höfn (Iceland)
Seatex RS
MTB RS
Hönefoss (N)
Processing Facility
NLES
Rotterdam (NL)
Scilly Isles (GB)
Toulouse (F)
Cadiz (E)
Kourou
(French Guyana)
Lario (I)
Fucino (I)
Matera (I)
Ankara (T)
Hartebeeshoek
(South Africa)
Copyright 2006 EUROCONTROL
38
ESTB to EGNOS
80 N
ECAC
60 N
40 N
20 N
0
IOR W
AOR-E
ARTEMIS
20 S
40 S
60 S
80 S
Minimum elevation angle contours for E=5 degrees
150 W
100 W
50 W
0
Copyright 2006 EUROCONTROL
50 E
100 E
150 E
39
EGNOS Performances: Horizontal Accuracy
Metres
NAV32516.3566
Copyright 2006 EUROCONTROL
40
EGNOS Performances: Vertical Accuracy
Meters
EGNOS Level 3A average VNSE (2σ) map
Copyright 2006 EUROCONTROL
41
EGNOS Stability Tests - September 2004
Copyright 2006 EUROCONTROL
42
Horizontal Accuracy - November 2005
Copyright 2006 EUROCONTROL
43
GALILEO/EGNOS Integration

3 Options:
– Cut Public Expenditure
Signals end of programme
 Loss of technical know how
 Loss of €310 Million

– Complete Independence
EU’s single European policy on satellite navigation?
 Duplication of effort and expenditure

– Full Integration
Technically
 Institutionally

NAV32516.3629
Copyright 2006 EUROCONTROL
44
EGNOS Operational Test and Validation:
Challenges

International acceptability

Distributed infrastructure

Institutional concerns

System complexity

Time/space performance dependence

WAAS/MSAS interoperability

Lessons learned for GBAS & Galileo
Copyright 2006 EUROCONTROL
45
Agenda

Space Based Augmentation Systems Principles

Implementations: EGNOS

Implementations: USA's WAAS

Implementations: Japan's MSAS
Copyright 2006 EUROCONTROL
46
WAAS: Initial Schedule

1983:
RTCA SC 159 chartered to study GPS for
aviation
– 1988:
DO-202 GPS MASPS
– 1994:
WAAS signal specification
– 1996:
DO-229 WAAS MOPS for en-route,
terminal & non-precision approach
– 1996+: WAAS MOPS for precision approach

1992:
FAA establishes National Satellite Testbed
(NSTB) to develop WAAS

1994:
FAA issues WAAS Request for Proposals

1996:
First contract for WAAS terminated & new
award made
Copyright 2006 EUROCONTROL
47
WAAS: Initial Schedule
Date
1997
Status
Flight Verification System (FVS)
2MCSs, 5WRSs, 2GES, 1GEO
1997-8 Initial WAAS Service Volume
 2MCSs, 24WRSs, 6GES, 2GEO
 Primary Means NPA, terminal & en-route
 Supplemental Means CAT-I
1999- End State WAAS
2001  Additional WRSs and GEO
 Primary Means for CAT-I
Copyright 2006 EUROCONTROL
48
WAAS: Original Schedule
00 01 02 03 04 05 06 07 08 09 10 11
?
Level - I I
WAAS
20
Supportability Upgrades
Level - I I I
Inmarsat (2 GEOs)
Acquisition
GEO # 1
SATs
GEO # 2
GEO # 3
GEO # 4 (If Required)
GPS
NAVAIDs
24 Satellites
Additional GPS ??
L5
Full
Copyright 2006 EUROCONTROL
49
WAAS: Independent Review Board

10 April 2001
– FAA should commit to WAAS
– Enormous benefits for all GPS Users
– LNAV and VNAV by 2003
– GEO Redundancy is biggest risk
GI51989_1000
Copyright 2006 EUROCONTROL
50
13 Feb 2002: Inspector General of DOT
FAA must decide whether to stop WAAS development in
2003 or continue to refine the technology to meet more
demanding precision approach capability known as a
Category precision approach.
The current implementation does not lead to cost savings
NAVGI51989_1006
Copyright 2006 EUROCONTROL
51
WAAS Schedule Update
00 01 02 03 04 05 06 07 08 09 10 11
20
Level - I I
WAAS
IOC
FOC
Supportability Upgrades
Inmarsat (POR and AOR-W)
GEOs
Acquisition
GEO # 3
Acquisition
GEO # 4
?
GEO # 3
If Required
Average of 27 Satellites Available
GPS
L5
IOC
FOC
GPS III
NAVAIDs
Full
Copyright 2006 EUROCONTROL
?
52
WAAS
WAAS
GEO + GPS satellites
Ground
Earth
Station
Wide Area
Master Station
EGNOS
Wide Area
Reference Stations
Copyright 2006 EUROCONTROL
53
WAAS Service Area
Copyright 2006 EUROCONTROL
54
WAAS Future GEO Coverage
POR
AOR-W
GALAXY XV
ANIK F1R
Copyright 2006 EUROCONTROL
55
PRN 22 Failure on 28 July 2001
On Canadian Space Geodesy Forum (24 Aug 2001)
Late on 28 July 2001, PRN22 sufferred a
clock failure and the satellite broadcast
erroneous data for over an hour.….
…It appears that as soon as the receiver
started tracking PRN22, the position solution
became in error by about a couple of hundred
kilometres.
Richard B. Langley
Geodetic Research Laboratory Dept. of
Geodesy and Geomatics Engineering
GI51987_1001
Copyright 2006 EUROCONTROL
56
WAAS and the PRN 22 Failure on 28 July 2001
First Step: Immediately
Second Step
Broadcast Clock
Corrections
Declare satellite
unusable
6 Minutes
NAVGI51989_1004
Copyright 2006 EUROCONTROL
57
WAAS Vertical Performance
Copyright 2006 EUROCONTROL
58
Agenda

Space Based Augmentation Systems Principles

Implementations: EGNOS

Implementations: USA's WAAS

Implementations: Japan's MSAS
Copyright 2006 EUROCONTROL
59
Implementations: Japan's MSAS

MSAS (MTSAT Satellite Based Augmentation System)
based on ICAO FANS concept & provides:
– GNSS for navigation
– Aeronautical Mobile Satellite Service (AMSS) for two way
voice/data including ADS

Hosted on Multi-functional Transport Satellite (MTSAT),
which has aeronautical & meteorological mission.

First launch in 1999,

Subsequent launches every 5 years

1994: Initiate design of MSAS

1996-2000: First phase of development

1999: Launch Failed!
Copyright 2006 EUROCONTROL
60
15 November 1999
Copyright 2006 EUROCONTROL
61
MTSAT-1 Launch Failure

The National Space Development Agency of Japan
(NASDA) launched the H-II Launch Vehicle No.8 carrying
the Multi-functional Transport Satellite (MTSAT) from
Tanegashima Space Center at 16:29, Nov. 15, 1999
(JST). However, the vehicle went out of the planned flight
path due to the abnormal stoppage of the combustion of
the 1st stage engine, and the command for destruction
was sent to the H-II Launch Vehicle No.8.

In this reason, it became impossible to inject MTSAT into
the orbit as planned.
Replacement: MTSAT-1R, Launch 2003 2004 2005
Copyright 2006 EUROCONTROL
62
MSAS
MTSAT-1R
MTSAT-2
GPS
GPS
Overlay
Primary
Ka/Ku
L1 / L2
GMS
GMS
GMS
Naha FukuokaTokyo Sapporo
ACC ACC ACC ACC
MCS
NES
CPF
NCS
MRS
GMS
MRS
GMS
L1/L2
MRS
Hawaii Australia
NES-1 NES-2
NES-1 NES-2
CPF
CPF
NCS
NCS
Master Control Station
Kobe MCS
Navigation Ground Earth Station
Central Processing Facility
Network Communication System
Monitoring and Ranging Station
Ground Monitor Station
Copyright 2006 EUROCONTROL
Ibaraki MCS
International
Network
63
MSAS Service Area
AOR-E
IOR
MTSAT POR
Copyright 2006 EUROCONTROL
AOR-W
64
End of this Module
DATE/TIME
09:00
12:30
Monday
20/03/06
Introduction
Tuesday
21/03/06
Satellite Navigation: Theory and Application
Wednesday
22/03/06
Thursday
23/03/06
Friday
24/03/06
From GPS to GNSS
13:30
Terrestrial Navigation
Airborne Based Augmentation Systems
Ground Based Augmentation Systems
Towards the Future
16:30
The History of Satellite Navigation
Current System
Status
GLONASS
Navigating with GPS
Space Based Augmentation Systems
Data Integrity
Modernisation Programmes
Debrief
Copyright 2006 EUROCONTROL
65