Upload
unity
View
42
Download
0
Tags:
Embed Size (px)
DESCRIPTION
GLOBAL POSITIONING SYSTEM Status and U.S. Policy Update. Swedish Radio Navigation Seminar Stockholm, Sweden October 21, 2008. Charles Daniels Senior Advisor, National Coordination Office United States of America. Overview. Introduction Global Positioning System Modernization Plans - PowerPoint PPT Presentation
Citation preview
UNITED STATES OF AMERICA
GLOBAL POSITIONING SYSTEM
Status and U.S. Policy UpdateSwedish Radio Navigation Seminar
Stockholm, SwedenOctober 21, 2008
Charles DanielsSenior Advisor, National Coordination Office
United States of America
22
Overview
• Introduction• Global Positioning System• Modernization Plans• U.S. Policy
33
Space-Based PNT Applications Impact A Wide Range of Economic Activities
4
OilExploration
Fishing & BoatingAviation Surveying &
Mapping
Trucking & Shipping
Satellite Operations
Precision Agriculture
Power GridManagement
Personal Navigation
CommunicationsNetwork
Synchronization
44
Introduction• Like the Internet, GPS is a critical component of
the global information infrastructure – Scalable applications enabling broad new capabilities – Facilitating innovations in efficiency, safety,
environmental protection, public security and science
• During the past decade, GPS has grown into a global utility providing space-based positioning, navigation and timing (PNT) – Consistent, predictable, dependable policy and
performance– Augmentations improve performance
5
GPS Introduction• Owned and operated by the U.S. Government
– Funded by U.S. taxpayers– Managed at a national level as a multi-use asset– Acquired and operated by the U.S. Air Force on behalf of
the U.S. Government per US Law Title 10, Section 2281– 30 years of operation – 1st launch February 1978
• GPS service is a one-way broadcast, like FM radio– Unlimited number of users – Civil GPS signals are free of direct user fees
• Public domain documentation– Available on an equal basis to users and industry – Anyone in the world can develop GPS user equipment
66
Overview
• Introduction• Global Positioning System• Modernization Plans• U.S. Policy
77
The Global Positioning System
• Baseline 24 satellite constellation in medium earth orbit
• Global coverage, 24 hours a day, all weather conditions
• Satellites broadcast precise time and orbit information on L-band radio frequencies
• Two types of signals:– Standard (free of direct user fees)– Precise (U.S. and Allied military)
• Three segments: – Space– Ground control– User equipment
88
GPS Constellation Status
• 33 Satellites on Orbit– 13 Block IIA– 12 Block IIR– 6 Block IIR-M– 2 Block IIA Spares
• Next launchs: – March 2009 – IIR-M 20– August 2009 – IIR-M 21 (Last IIR)– October 2009 – 1st Launch of IIF
31 Healthy SatellitesAs of October 17, 2008 (Baseline Constellation: 24)
99
GroundAntenna
Master Control Station (Schriever AFB)
GPS Operational Control Segment (OCS)
AscensioAscensionn
Diego Diego GarciaGarcia
Cape Cape CanaveralCanaveralHawaiiHawaii
Kwajalein Kwajalein
Schriever Schriever AFB AFB
ColoradoColorado S KoreaS Korea
AustraliaAustralia
BahrainBahrain
S AfricaS Africa
EnglandEngland
ArgentinaArgentina
EcuadorEcuador
TahitiTahiti
USNOUSNO
AlaskaAlaska
MonitorStation
New New ZealanZealandd
Vandenberg Vandenberg AFB AFB
CaliforniaCalifornia
NGA Monitor StationOCS Monitor Station
Ground Antenna Future Monitor Station
Master Control StationBackup Master Control Station
1010
GPS Signal in Space Performance
Global GPS civil service performance commitmentcontinuously met since 1993 (15 yrs)
Decreasing range error
Performance Standard
4.6 4.3
3.0 2.72.1 1.8 1.5
1.1
0
1
2
3
4
5
6
7
1990 1992 1994 1996 1997 1999 2001 2005
RMS
User
Ran
ge E
rror (
m)
2007
.92
1111
GPS SPS PS UPDATECOMPARISON OF GPS SPS PERFORMANCE PARAMETERS
GPS Performance Standard Metric
SPS Signal Specification August 1998
(user performance)
SPS Performance Standard October 2001(signal in space)
SPS Performance Standard
September 2008 *
(signal in space)
CY 2007Performance**
1
Global Accuracy All-in-View Horizontal 95% All-in-View Vertical 95%
≤ 100 meters≤ 156 meters
≤ 13 meters≤ 22 meters
≤ 9 meters≤ 15 meters
2.32 meters4.45 meters
2
Worst Site Accuracy All-in-View Horizontal 95% All-in-View Vertical 95%
≤ 100 meters≤ 156 meters
≤ 36 meters≤ 77 meters
≤ 17 meters≤ 37 meters
3.63 meters4.95 meters
3 User Range Error (URE) NONE
≤ 6 meters RMS(Constellation RMS
URE)
≤ 7.8 meters 95%, (Worst Satellite URE) equivalent to 4 m
RMS
2.29 meters RMS(Worst Satellite
URE)
4 Geometry (PDOP ≤ 6)
≥ 95.87% global ≥ 83.92% worst site
≥ 98% global ≥ 88% worst site
≥ 98% global ≥ 88% worst site
99.988% global 98.958% worst
site
5 Constellation Availability NONE
≥ 95% Probability of 24 Healthy Satellites ≥ 98% Probability of 21 Healthy Satellites
(assumes 24 primary slots)
≥ 95% Probability of 24 Healthy Satellites ≥ 98% Probability of
21 Healthy Satellites≥ 99.999%
Probability of 20 Healthy Satellites
(assumes 24 primary slots)
100% Probability of 22 Healthy
Satellites in 24 primary slots(FY2008) ***
* Green color indicates improvement in U.S. Government commitment to GPS civil service** As measured and reported at web site (http://www.nstb.tc.faa.gov/)*** As measured and reported at web site (http://www.gps.afspc.af.mil/gpsoc/)
12
International Augmentations
Differential GPS Networks
International GNSS Service Global Differential GPS System
Space-Based Augmentation Systems
1313
Overview
• Introduction• Global Positioning System• Modernization Plans• U.S. Policy
1414
Recent GPS Improvements
• Launched 3 modernized satellites in past year– Largest GPS constellation size ever– Second Civil Signal (L2C) now on orbit
• Transitioned to modernized master control station– Improved operational flexibility and responsiveness– Added backup control station
• Expanded GPS ground network to triple amount of monitor data sent to control station– 10-15% improvement in accuracy of GPS data
broadcast
1515
Block IIA/IIR Block IIIBlock IIR-M, IIF• Backward compatibility
• 4th civil signal (L1C)• Increased accuracy• Increased anti-jam power
• Assured availability• Navigation surety• Controlled integrity• Increased security• System survivability
IIR-M: IIA/IIR capabilities plus• 2nd civil signal (L2C)•M-Code (L1M & L2M)IIF: IIR-M capability plus• 3rd civil signal (L5)• Anti-jam flex power
Basic GPS• Standard Service– Single frequency (L1)– Coarse acquisition
(C/A) code navigation• Precise Service– Y-Code (L1Y & L2Y)– Y-Code navigation
Increasing System Capabilities Increasing Defense / Civil Benefit
GPS Modernization Program
16
Modernized GPS – New Signals• Second civil signal (“L2C”)
–Designed to meet commercial needs–Higher accuracy through ionospheric correction–Began with GPS Block IIR-M in Sep 2005; 24 satellites: ~2014
• Third civil signal (“L5”)–Designed to meet demanding requirements for transportation safety (safety-of-life)
–Uses highly protected Aeronautical Radio Navigation Service (ARNS) band–First launch: ~2009 (GPS IIR-M Demo); ~2009 (GPS IIF); 24 satellites: ~2016
• Fourth civil signal (“L1C”)–Designed with international partners to enable GNSS interoperability–Begins with GPS Block III; First launch: ~2014; 24 satellites: ~2021
17
Benefits of GPS Modernization
•System-wide improvements in accuracy, availability, integrity, and reliability to:– Meet increasing civil, commercial and military
demands• Higher standalone accuracy • More robust against interference • Provides separate more secure Military signal• Full capability of second (L2C) and third (L5) civil signals• Full Capability of L1C for interoperability with other GNSS• Improved indoor, mobile, and urban use
1818
GPS III Update
• Contract for GPS III-A satellites awarded in May 08– Selective Availability feature to be eliminated– First Launch 2013
• Contracts for Next-Generation Operational Control Segment (OCX) awarded in January 08– Will implement full functionality of L2C and L5
• Future increments of GPS III will incorporate additional capabilities– As technology matures and new requirements
are validated
1919
Overview
• Introduction• Global Positioning System• Modernization Plans• U.S. Policy
2020
U.S. Policy History• 1978: First GPS satellite launched• 1983: U.S. President offers free
civilian access to GPS• 1996: U.S. policy establishes joint
civil/military GPS management• 1997: U.S. Congress passes law that civil GPS shall be
provided free of direct user fees• 2000: U.S. President set Selective Availability to “Zero”• 2004: U.S. President issues U.S. Policy on Space-Based
PNT• 2007: U.S. President announces Selective Availability
will no longer be built into modernized GPS III satellites
2121
U.S. Policy Promotes Global Use of GPS Technology
• No direct user fees for civil GPS services– Provided on a continuous, worldwide basis
• Open, public signal structures for all civil services– Promotes equal access for user equipment
manufacturing, applications development, and value-added services
– Encourages open, market-driven competition• Global compatibility and interoperability with GPS• Service improvements for civil, commercial, and
scientific users worldwide• Protection of radionavigation spectrum from
disruption and interference
2222
WHITE HOUSE
ADVISORY BOARD
Sponsor: NASA
NATIONALEXECUTIVE COMMITTEEFOR SPACE-BASED PNTExecutive Steering GroupCo-Chairs: Defense, Transportation
NATIONAL COORDINATION OFFICE
Host: Commerce
National Space-Based PNT Organization
GPS International Working Group
Chair: State
Engineering ForumCo-Chairs: Defense,
Transportation
Ad HocWorking Groups
DefenseTransportation
StateInterior
AgricultureCommerce
Homeland SecurityJoint Chiefs of Staff
NASA
2323
Keys to the Global Success of GPS• Program Stability and Performance
– Civil service performance commitment met continuously since December 1993
– Continuity of constellation and signals ensured through Air Force operation and acquisition
– Continuous improvements in accuracy, availability, etc.– Funding through U.S. taxpayers
• Policy Stability and Transparency– Open access to civil GPS signals, free of direct user fees– Open, free, and stable technical documentation– Market-based competition worldwide– Liberal export controls on GPS user equipment– National-level policy coordination including civil and military
leaders• Commercial Entrepreneurship and Investment
24
U.S. Cooperation Efforts• Cooperative relationships
established with Europe, Japan, Russia, India, Australia
• U.S. goals:– Compatibility and interoperability– National security– Level playing field in global
markets• Multilateral cooperation
– International Committee on GNSS
– ICAO, IMO, NATO
25
Goal of Civil Interoperability
Ideal interoperability provides users a PNT solution using signals from different GNSS systems– No additional
receiver cost or complexity
– No degradation in performanceInteroperable = Better Together Than
Separate
26
Summary
• GPS performance is better than designed– New Civil GPS signal (L2C) now available on 6
satellites– Modernization will bring additional
improvements in Accurary and Availability.• Implementing U.S. National Space-Based PNT
Policy – National Executive Committee directly
engaged• U.S. policy encourages and promotes
worldwide use of civil GPS and augmentationsInternational cooperation through GNSS
compatibility and interoperability is a U.S. priority
2727
For Additional Information…
Briefing available at:http://PNT.gov
28
Contact Info
Charles DanielsNational Coordination Office for Space-Based PNT
Washington, DC 20230
Tele: 202-482-6726 Email: [email protected]
Web sites: http://pnt.govhttp://gps.gov