U.S. Space-Based Positioning, Navigation and Timing: A Policy and Program Review

1
U.S. Space-Based Positioning, Navigation and
Timing A Policy and Program Review
Polytechnic University of Turin

• 25 February 2008

Michael Shaw, Director U.S. National Coordination
Office for Space-Based Positioning, Navigation,
and Timing (PNT)
2
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, public security and science
• In 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

3
GPS as a Global Public Service

• Owned and operated by the U.S. Government
• Paid for by U.S. taxpayers
• Managed at a national level as multi-use asset
• Acquired and operated by the U.S. Air Force on
  behalf of the U.S. Government
• GPS service is a one-way broadcast, like FM radio
• Unlimited number of users
• Access to civilian GPS signals is free of direct
  user charges
• Public domain documentation
• Available on an equal basis to users and industry
  
• Anyone in the world can develop GPS user equipment

4
Overview

• Systems
• Applications
• Policy
• International Cooperation

5
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

6
Current Constellation
30 GPS Satellites Set Healthy (as of 14 Feb
08) (Baseline Constellation 24)

• 13 Block IIA satellites operational
• 12 Block IIR satellites operational
• 5 Block IIR-M satellite operational
• Transmitting new second civil signal (L2C)
• Continuously assessing constellation health to
  determine launch need
• Next launch March 2008
• Global GPS civil service performance commitment
  has been met continuously since December 1993

7
GPS Modernization Program
Increasing System Capabilities w Increasing
Defense / Civil Benefit
Block IIA/IIR
Block III
Block IIR-M

• Backward compatibility
• 4th civil signal (L1C)
• Increased accuracy
• Assured availability
• Increased security
• System survivability
• Begin launch 2014

• IIR-M IIA/IIR capabilities plus
• 2nd civil signal (L2C)
• M-Code (L1M and L2M)
• Currently being launched
• IIF IIR-M capability plus
• 3rd civil signal (L5)
• Begin launch 2009

• Basic GPS
• Standard Service
• Single frequency (L1)
• Coarse acquisition (C/A) code navigation
• Precise Service
• Y-Code (L1Y and L2Y)
• Y-Code navigation

Block, IIF
8
Modernized GPS Civil Signals

• Second civil signal (L2C)
• Designed to meet commercial needs
• Higher accuracy through ionospheric correction
• Higher effective power and improved data
  structure reduce interference, speed up signal
  acquisition, enable miniaturization of receivers,
  may enable indoor use
• 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
• Begins with GPS Block IIF
• First launch 2008 (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

9
Benefits of GPS Modernization

• System-wide improvements in accuracy,
  availability, integrity, and reliability for all
  users
• Higher standalone accuracy
• Augmentations likely will still remain
• More robust against interference
• Operational capability for second (L2C) and third
  (L5) civil signals
• In combination with GPS IIR-M and IIF satellites
• Delivers L1C for interoperability with Galileo
  and other GNSS
• Improved indoor, mobile, and urban use

10
GPS Program Update

• New GPS Operational Control Segment -- September
  2007
• Upgrading GPS ground segment OCX 2012 - 2016
• Will implement full functionality for L2C and L5
• Contract awarded January 2008
• Acquiring next generation of GPS satellites GPS
  IIIA
• In source selection - anticipate contract award
  early 2008
• GPS SPS Performance Standard update in progress
  Apr 08

11
Continuous Performance Improvement

• Key measures of Effectiveness to evaluate GPS
  services
• Accuracy
• Bounded inaccuracy
• Assured Availability
• Integrity
• Resistance to RF Interference/Jamming

Accuracy
Performance Standard
Decreasing range error
Year
12
Augmentation Systems
SBAS
GBAS

• Improves basic GPS performance (e.g. accuracy,
  integrity, etc)
• Sub-centimeter accuracy for geodesy, geology,
  etc.
• 2-5 cm accuracy for real-time positioning,
  surveying, etc.
• lt3 m vertical accuracy with 6 second time to
  alarm for aviation

13
Augmentations
Satellite-Based Augmentations
Ground-Based Augmentations (NDGPS, CORS, LAAS,
etc.)
14
Satellite-Based Augmentations

• Geostationary satellites provide regional
  coverage
• GPS-like signals enable simplified receivers
• International Partner Service Providers
• US (WAAS), Europe (EGNOS), Japan (MTSAT), and
  India (GAGAN)
• WAAS operational Jul 03 Expanding capability
  with L5
• GPS-based EGNOS leading way for Galileo
• Independent signal monitoring supports the
  interests of each individual State
• International assured aviation integrity standard

15
U.S. GPS Augmentation Update

• Wide Area Augmentation System commissioned in
  2003
• Two GEO satellites launched in 2005 (Galaxy XV
  Anik F1R)
• Provides dual satellite coverage over the U.S.
• Service expanded into Canada and Mexico
  operational Sep 07
• New reference stations (5 Mexico and 4 Canada)
• Nationwide DGPS System (NDGPS)
• Maritime, rail, survey, precision agriculture,
  weather forecasting, and resource management
• International standard in over 50 countries
• DOT completing assessment for inland component
• Maritime NDGPS component remain operational

16
Overview

• Systems
• Applications
• Policy
• International Cooperation

17
Commercial GNSS Applications Span A Wide Range
of Economic Activities
Satellite Operations
Power Grid Management
Personal Navigation
Surveying Mapping
Trucking Shipping
Aviation
Communications Network Synchronization
Recreation
Railroads
Fishing Boating
Offshore Drilling
16
18
Civil GNSS Applications

• Enabling technology
• New applications emerging every day
• 68 Billion industry worldwide by year 2010
• Wide use in transportation safety
• Aviation, maritime, railroad, highway, etc.
• Potential to reduce land-based navigation systems
• Centerpiece of future transportation
  infrastructure
• Wide range of civil uses
• Telecommunications, surveying, law enforcement,
  emergency response, agriculture, mining, etc.
• Used in conjunction with remote sensing

19
Aviation

• Reliable and accurate positioning worldwide
• Reduced delays
• More fuel-efficient routes
• Increased system capacity with enhanced safety

Maritime
20
Maritime

• Large ships, fishing recreation boats
• Harbor entrance and approach
• Regardless of visibility
• Hydrographic Survey
• Buoy Positioning, etc.

21
Railroads

• Enhances safety
• Reduces accidents
• Increases capacity and efficiency
• Closer train spacing reduces investments
• Reduces fuel consumption
• Rapid rail structure and condition mapping
• Improves maintenance capability
• Increased efficiency and capacity through
  positive train control
• Tracking location of vehicles/containers
• Rapid rail structure and conditioning mapping

22
GNSS Applications Improving Highway Operations

• Vehicle Infrastructure Integration
• (VII)
• Improving safety and reducing congestion will
  require more efficient management of the roadway
  system
• Vehicle-highway information exchange is key to
  improved management and operation of the
  transportation network
• Provide information on traffic conditions,
  crashes, adverse weather and road conditions,
  etc.

23
GNSS Applications
Automatic Vehicle Location

• Cargo Fleet Tracking
• Improves safety and security
• Fleet Control/Dispatch
• Increases fuel savings
• Improves asset management
• Emergency Operations
• Reduces response times
• Reduces injury and property loss
• Road Maintenance
• In Vehicle Navigation
• Determines accurate position
• Reduces air pollution

24
Surveying/Mapping/GIS

• Sub-centimeter accuracy
• 100-300 savings in time, cost, labor
• Most major development projects require surveying
• Rural electrification
• Telecom tower placement
• Pipeline installation
• Dam construction
• Port dredging operations
• Oil, gas, and mineral exploration
• Flood plain mapping

25
Precision Agriculture

• Maximize use of resources
• Optimize plowing of crop rows
• Tailor applications of seeds, fertilizer, water,
  pesticides
• Improve management of land, machinery, personnel,
  time
• Greater crop yields
• Net benefit 5-14 per acre
• Minimize environmental impacts
• Localize identification and treatment of
  distressed crops that reduces chemical use
• Precisely level fields to prevent fluid runoff

26
Environmental Protection

• Forest protection
• Logging enforcement (e.g., Mato Grosso)
• Firefighting
• IBAMA 230 GPS units
• Fishing boundary enforcement
• Endangered species and habitat preservation
• Natural resource management
• Hazardous cleanup
• Oil spills, toxic waste
• Atmospheric modeling

27
Scientific Research

• Monitoring geological change
• Glaciers, tectonic plates, earthquakes, volcanoes
• Wildlife behavior
• Atmospheric modeling
• Water vapor content
• Oceanic studies
• Tidal patterns
• Surface mapping
• Time transfer
• Space Exploration

28
Timing

• GPS offers an inexpensive alternative to costly,
  high maintenance timing equipment
• Telecommunications network synchronization
  management
• Phones, pagers, wireless systems
• LANs, WANs, Internet
• Financial transactions, e-commerce
• Electrical power grid management fault location

29
New Applications Emerging Every Day

• Wireless/mobile applications
• Child/pet tracking
• Spacecraft control
• Power grid management
• Open pit mining
• Automatic snowplow guidance

30
Snow Plow Video
31
Overview

• Systems
• Applications
• Policy
• International Cooperation

32
U.S. Policy History

• 1978 First GPS satellite launched
• 1983 U.S. President offers free civilian access
  to GPS
• 1996 First U.S. GPS Policy. Established GPS a
  dual-use system under joint civil/military
  management

• 1997 U.S. Congress passes law requiring civil
  GPS to be provided free of direct user fees
• 2000 U.S. President set Selective Availability
  to Zero
• 2004 U.S. President issued U.S. Policy on
  Space-Based PNT
• 2007 U.S. President announces Selective
  Availability will no longer be built into
  modernized GPS III satellites

33
2004 U.S. Space-Based PNT Policy
GOAL Ensure the U.S. maintains space-based PNT services, augmentation, back-up, and service denial capabilities that GOAL Ensure the U.S. maintains space-based PNT services, augmentation, back-up, and service denial capabilities that
ASSURES SERVICE Provide uninterrupted availability of PNT services
MEETS DEMANDS Meet growing national, homeland, economic security, and civil requirements, and scientific and commercial demands
LEADS MILITARILY Remain the pre-eminent military space-based PNT service
STAYS COMPETITIVE Continue to provide civil services that exceed or are competitive with foreign civil space-based PNT services and augmentation systems
INTEGRATES GLOBALLY Remain essential components of internationally accepted PNT services
LEADS TECHNICALLY Promote U.S. technological leadership in applications involving space-based PNT services
34
National Space-Based PNTOrganization Structure
WHITE HOUSE
Defense
Transportation
NATIONALEXECUTIVE COMMITTEEFOR SPACE-BASED
PNT Executive Steering Group Co-Chairs Defense,
Transportation
State
ADVISORY BOARD Sponsor NASA
Agriculture
Commerce
Homeland Security
NATIONAL COORDINATION OFFICE Host Commerce
Interior
Joint Chiefs of Staff
NASA
GPS International Working Group Chair State
Engineering Forum Co-Chairs Defense,
Transportation
Ad HocWorking Groups
35
National Space-Based PNT Executive
Committee

• National Space-Based PNT Executive Committee
  established in 2004 U.S. Policy
• Chaired by Deputy Secretaries of Defense and
  Transportation
• Membership includes State, Agriculture,
  Interior, Commerce, Homeland Security, JCS and
  NASA
• Supported by a new National Coordination Office
• National Coordination Office (NCO) was
  established with staff from each member agency
• Director, Deputy Director, and 6 staff

36
National Coordination Office

• Facilitates information sharing, coordination,
  and issue resolution regarding space-based PNT
  programs, requirements, budgets, and policies
  across all U.S. Agencies
• Facilitates coordination among Agencies regarding
  plans to modernize U.S. space-based PNT
  infrastructure
• Conducts or oversees space-based PNT studies,
  analyses and projects with a U.S. National
  benefit
• Informs state, local and international GNSS users
  and participants of National Executive Committee
  activities

37
Advisory Board

• Conducts assessments makes recommendations to
  the Executive Committee in support of national
  policy goals and objectives for space-based PNT
• Twenty-four members 6 international members
• Met twice in 2007
• Next meeting 27-28 March 2008

38
EXCOM Activities

• Program Oversight
• Five-Year National Plan
• National PNT Architecture
• GPS Modernization
• Civil GPS Funding
• GPS Augmentations
• Nationwide Differential GPS
• Distress Alerting Satellite System (DASS)
• International Engagement
• Bilateral
• Multilateral

• Spectrum Management
• Interference Detection and Mitigation Plan
• Spectrum Protection Plan
• Outreach
• Publications, websites, exhibits
• Conferences and other venues
• Coordination of U.S. message

39
Selective Availability

• Selective Availability (SA) feature was used in
  the past to intentionally degrade civilian GPS
  service
• First fully implemented in 1995
• Discontinued (set zero) by the President in May
  2000
• Has not been used since then
• USG made decision that the next generation of GPS
  satellites (GPS III) will be built without the
  Selective Availability feature
• Secretary of Transportation Peters announced
  decision at ICAO General Assembly on 18 September
  2007

40
2004 U.S. Policy

• Demonstrates U.S. Government commitment to
  space-based PNT for all stakeholders
• Provides framework for public/private decision
  makers
• Improves ability to coordinate efforts across the
  various agencies of the U.S. Government
• Creates basis for meaningful dialogue between
  service providers and end users
• Promotes common standards for worldwide
  interoperability

41
Overview

• Systems
• Applications
• Policy
• International Cooperation

42
Active Diplomacy

• Results of over a decade of bilateral/multilateral
  diplomatic efforts are beginning to be seen
• New satellite constellations and regional
  augmentation systems, while independently owned
  and operated, are being designed to be compatible
  and interoperable
• Coordination mechanisms are being created to
  promote interoperability, promote GNSS use, and
  ensure a level playing field in the global
  marketplace

43
Compatibility - Interoperability

• Compatible ability of U.S. and non-U.S. space
  based PNT services to be used separately or
  together without interfering with each individual
  service or signal
• Compatibility should also involve spectral
  separation between each systems authorized
  service signals and other systems signals
• Interoperable ability of civil U.S. and
  non-U.S. space-based PNT services to be used
  together to provide the user better capabilities
  than would be achieved by relying solely on one
  service or signal

Interoperable Better Together than Separate
44
U.S. Policy Principles
Outlined in 2004 Presidential Policy on
Space-Based Positioning, Navigation, and Timing
(PNT)

• Provide civil GPS and augmentations free of
  direct user fees on a continuous, worldwide basis
• Provide open, free access to information needed
  to develop equipment
• Improve performance of civil GPS and
  augmentations to meet or exceed that of
  international systems

• Encourage international development of PNT
  systems based on GPS
• Seek to ensure international systems are
  interoperable with civil GPS and augmentations
• Address mutual security concerns with
  international providers to prevent hostile use

45
GPS-Galileo Cooperation

• 2004 US-EU agreement provides a solid foundation
  for cooperation
• Action now divided among four working groups set
  up by the agreement
• Technical, trade, and security issues working
  groups have already met
• Improved new civil signal (MBOC) adopted in July
  2007

June 26, 2004, press conference at U.S.-EU Summit
in Ireland (U.S. Sec. of State Colin Powell,
Irish Foreign Minister Brian Cowen, EU
Vice-President Loyola De Palacio)
46
GPS-GLONASS Cooperation

• U.S.- Russia Joint Statement issued in Dec 2004
• Several productive technical working group
  meetings have been held
• Russia WG-1 chair proposed adopting two new civil
  CDMA signals at L1, L5 which will be
  interoperable with GPS
• Negotiations for a U.S.-Russia agreement on
  satellite navigation cooperation have been
  underway since late 2005
• Next meeting will be held in early 2008

47
U.S. Japan Cooperation

• Japans status as a world leader in GPS
  applications and user equipment makes it an
  important partner
• Regular policy consultations and technical
  meetings on GPS cooperation have been held since
  1996 and led to the 1998 Clinton-Obuchi Joint
  Statement
• Both countries have benefited from the close
  relationship
• QZSS is designed to be compatible and
  interoperable with GPS
• U.S. working with Japan to set up QZSS monitoring
  stations in Hawaii and Guam

48
U.S.-India Cooperation

• Policy and technical consultations on GPS
  cooperation underway since 2005
• One aim is to ensure interoperability between GPS
  augmentation system WAAS and Indias planned
  GAGAN augmentation system based on GPS
• Another important topic is ionospheric distortion
  and solutions
• U.S.-India Joint Statement on GNSS Cooperation
• Issued in Feb 2007 in Washington
• Bi-lateral meeting held in Bangalore in Sep 2007

49
U.S.-Australia Cooperation

• Long history of GPS cooperation between U.S. and
  Australia
• U.S.-Australia Joint Delegation Statement on
  Cooperation in the Civil Use of GPS signed Apr 19
• Cooperation expands upon existing efforts to
  ensure interoperability between GPS and
  Australia's Ground-based Regional Augmentation
  System (GRAS) and Ground Based Augmentation
  System (GBAS)
• U.S. Coast Guard NAVCEN posts a daily Position
  Dilution of Precision (PDOP) report in response
  to Australias concerns over planned GPS outages

50
International Committee on Global Navigation
Satellite Systems (ICG)

• Emerged from 3rd UN Conference on the Exploration
  and Peaceful Uses of Outer Space Jul 1999
• Promote the use of GNSS and its integration into
  infrastructures, particularly in developing
  countries
• Encourage compatibility and interoperability
  among global and regional systems
• Members include GNSS providers (U.S., EU,
  Russia, China, India, Japan), international
  organizations, and international associations

51
2nd International Committee on Global
Navigation Satellite Systems (ICG)

• ICG-2 held in September in Bangalore, India
• Established Providers Forum to address common
  issues
• Exchanged views on the ICG Work Plan by work
  groups
• A. Interoperability and compatibility
• B. Enhancement of performance of GNSS services
• C. Information dissemination, education, outreach
  coordination
• D. Interactions with National and Regional
  Authorities as well as International
  Organizations
• U.S. will host the 3rd ICG in Dec 2008

52
Summary

• U.S. Space-based PNT effort progressing
  significantly in areas of policy, programs and
  international
• Continuing to improve USG space-based PNT system
  performance
• New GNSS applications emerging
• Implementation of 2004 Policy proceeding well
• Very active senior USG leadership
• International cooperation is a top priority for
  USG
• Actively engaged in multi-lateral/bi-lateral
  consultations

As new space-based GNSS emerge globally,
compatibility and interoperability is the key to
success for all
53
Contact Information
Michael E. Shaw Director U.S. National
Coordination Office for Space-Based PNT 14th and
Constitution Ave, N.W. Washington, D.C. 20230
Ph [phone] Fax (202)
482-4429 Michael.Shaw_at_pnt.gov Presentation and
other GPS information available www.PNT.gov
54
Web-based Information

• PNT.gov established to distribute information on
  the U.S. National Executive Committee
• Information on U.S. Policy, Executive Committee
  membership, Advisory Board and frequently asked
  questions
• Recent announcement on Selective Availability and
  offer letter to International Civil Aviation
  Organization
• All recent public presentation
• GPS.gov established for public information about
  GPS applications
• Available in English, French, Spanish, Arabic and
  Chinese
• Brochure also available in hardcopy upon request
• Contains additional links to various other web
  sites