U S SpaceBased PNT Policy International Cooperation April

U. S. Space-Based PNT Policy & International Cooperation April 7, 2008 David A. Turner, Deputy Director Office of Space and Advanced Technology Bureau of Oceans, Environment and Science U. S. Department of State

Introduction • Like the Internet, GPS has become a critical component of the global information infrastructure – Consistent policy and predictable, dependable performance – Augmentations improve service performance • Presentation will address: – U. S. Space-Based Positioning, Navigation, and Timing Policy – Diplomatic efforts to ensure cooperation in providing Global Navigation Satellite Systems and Services Moscow Satellite Navigation Forum 2008 2

U. S. Policy History • 1978: First GPS satellite launched • 1978: Legislation requires federal radionavigation planning • 1983: U. S. President offers free civilian access to GPS • 1996: First U. S. GPS Policy. Established GPS as a dual-use system under joint civil/military management • 1997: U. S. Congress passes law requiring the GPS standard positioning service 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 Moscow Satellite Navigation Forum 2008 3

U. S. Policy Principles Outlined in 2004 Presidential Policy on Space. Based Positioning, Navigation, and Timing (PNT) • Provide civil GPS and • Encourage international augmentations free of direct development of PNT systems user fees on a continuous, based on GPS worldwide basis • Seek to ensure international • Provide open, free access to systems are interoperable information needed to with civil GPS and develop equipment augmentations • Improve performance of civil • Address mutual security GPS and augmentations to concerns with international meet or exceed that of providers to prevent hostile international systems use Moscow Satellite Navigation Forum 2008 4

National Space-Based PNT Organization Structure WHITE HOUSE Defense Transportation State Interior Agriculture NATIONAL EXECUTIVE COMMITTEE FOR SPACE-BASED PNT ADVISORY BOARD Executive Steering Group Sponsor: NASA Co-Chairs: Defense, Transportation Commerce Homeland Security Joint Chiefs of Staff NATIONAL COORDINATION OFFICE Host: Commerce NASA GPS International Working Group Chair: State Moscow Satellite Navigation Forum 2008 Engineering Forum Co-Chairs: Defense, Transportation Ad Hoc Working Groups 5

2004 U. S. Space-Based PNT Policy (Excerpts focused on International Relations) Goals: • U. S. space-based PNT systems and services remain essential components of internationally accepted PNT services • Promote U. S. technological leadership in applications involving spacebased PNT services To achieve this, the United States Government shall: • Encourage foreign development of PNT services/systems based on GPS – Seek to ensure foreign space-based PNT systems are interoperable with civil GPS and augmentations – At a minimum, ensure compatibility The Secretary of State shall: • Promote the use of civil aspects of GPS and its augmentation services and standards with foreign governments and other international organizations • Lead negotiations with foreign governments and international organizations regarding civil PNT matters – And, as appropriate in coordination with the SECDEF, military PNT matters Moscow Satellite Navigation Forum 2008 6

Planned GNSS • Global Constellations – GPS (24+) • Satellite-Based Augmentations – GLONASS (24) – WAAS (3) – Galileo (27) – MSAS (2) – Compass (35) – EGNOS (3) – GAGAN (3) • Regional Constellations – SDCM (2? ) – QZSS (3) – IRNSS (7) Moscow Satellite Navigation Forum 2008 7

U. S. Objectives in Working with Other GNSS Service Providers • Ensure compatibility ― 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 – Radio frequency compatibility – Spectral separation between M code and other signals • Achieve interoperability – 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 – Primary focus on the common L 1 C and L 5 signals Pursue through Bi-lateral and Multi-lateral Cooperation Moscow Satellite Navigation Forum 2008 8

The Goal of RNSS Civil Interoperability GALILEO QZS GLONASS GPS • Ideal interoperability allows navigation with one signal each from four different systems with no additional receiver cost or complexity Interoperable = Better Together than Separate Moscow Satellite Navigation Forum 2008 9

U. S. - Europe Cooperation • US-EU agreement signed in 2004 provides solid foundation for cooperation • Action is now divided among four working groups set up by the agreement: – Technical, trade, and security issues working groups have 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) Moscow Satellite Navigation Forum 2008 10

U. S. - Russian Federation Cooperation • U. S. - Russia Joint Statement issued in December 2004 • Several very productive technical working group meetings have been held: – Russia WG-1 chair proposed adopting two new civil CDMA signals at L 1, L 5 to be interoperable with GPS – Still under discussion within the Russian Government • Negotiations for a U. S. -Russia Agreement on satellite navigation cooperation have been underway since late 2005 Moscow Satellite Navigation Forum 2008 11

U. S. - Japan Cooperation • Japan’s 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 Moscow Satellite Navigation Forum 2008 12

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 India’s 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 February 2007 in Washington – Bi-lateral meeting held in Bangalore in September 2007 – Technical Meeting focused on GPS-IRNSS compatibility and interoperability held in January 2008 Moscow Satellite Navigation Forum 2008 13

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 April 19, 2007 – Cooperation expands upon existing efforts to ensure interoperability between GPS and Australia's Groundbased 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 Australia’s concerns over planned GPS outages Moscow Satellite Navigation Forum 2008 14

International Committee on Global Navigation Satellite Systems (ICG) • Emerged from 3 rd UN Conference on the Exploration and Peaceful Uses of Outer Space July 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) – Other Member States of the United Nations – International organizations/associations Moscow Satellite Navigation Forum 2008 15

2 nd International Committee on Global Navigation Satellite Systems (ICG) • ICG-2 held in September in Bangalore, India • Established Providers Forum to address common issues • Began implementation of the ICG Work Plan within established working groups: – A. Interoperability and compatibility – B. Enhancement of performance of GNSS services – C. Information dissemination, education, outreach & coordination – D. Interaction with monitoring & reference station network organizations • U. S. will host the 3 rd ICG in December 2008 Moscow Satellite Navigation Forum 2008 16

ICG Providers Forum • Six space segment providers listed previously are members • Purpose: – Focused discussions on compatibility and interoperability, encouraging development of complimentary systems – Exchange of detailed information on systems and service provision plans – Exchange views on ICG work plan and activities • Consensus reached at the first meeting on general definitions for compatibility and interoperability – Including spectral separation between each system’s authorized service signals and other systems’ signals http: //www. unoosa. org/oosa/en/SAP/gnss/icg. html Moscow Satellite Navigation Forum 2008 17

Summary • International cooperation in the context of National Space-Based PNT Policy principles is a top priority for the U. S. Government • U. S. is actively engaged in bi-lateral and multilateral cooperation on space-based navigation issues • As new space-based GNSS are emerging globally, interoperability is the key to “success for all” Moscow Satellite Navigation Forum 2008

Contact Information David A. Turner Deputy Director Space and Advanced Technology U. S. Department of State OES/SAT, SA-23, Suite 410 Washington, D. C. 20520 202. 663. 2397 (office) 202. 320. 1972 (mobile) Turner. DA@state. gov http: //www. state. gov/g/oes/sat/ http: //pnt. gov/international/ Moscow Satellite Navigation Forum 2008

BACK-UP

ICG Providers Forum Definition of Compatibility refers to the ability of space-based positioning, navigation, and timing services to be used separately or together without interfering with each individual service or signal. • Radiofrequency compatibility should involve thorough consideration of detailed technical factors, including effects on receiver noise floor and cross-correlation between interfering and desired signals. The International Telecommunications Union (ITU) provides the framework for discussions on radiofrequency compatibility. • Compatibility should also involve spectral separation between each system’s authorized service signals and other systems’ signals. • Any additional solutions to improve compatibility are encouraged Moscow Satellite Navigation Forum 2008 21

Radio Frequency Compatibility • Ensures that signals do not unacceptably interfere with use of other signals • Requires thorough consideration of detailed technical factors, including – Effects on receiver noise floor – Crosscorrelation between interfering and desired signals • International Telecommunication Union (ITU) provides framework • Details are best worked bilaterally between providers Moscow Satellite Navigation Forum 2008 22

ICG Providers Forum Definition of Interoperability refers to the ability of open global and regional satellite navigation and timing services to be used together to provide better capabilities at the user level than would be achieved by relying solely on one service or signal. • Ideal interoperability allows navigation with signals from at least four different systems with no additional receiver cost or complexity. • Common center frequencies are essential to interoperability, and commonality of other signal characteristics is desirable. • Multiple constellations broadcasting interoperable open signals will result in improved observed geometry, increasing end user accuracy everywhere and improving service availability in environments where satellite visibility is often obscured. • Geodetic reference frames and system time standards should also be considered. • Any additional solutions to improve interoperability are encouraged. Moscow Satellite Navigation Forum 2008 23

Main Benefit of Interoperability Geometry • More Satellites Better Geometry Improves: – Satellite coverage navigate where could not before – Dilution of Precision accuracy is better everywhere • Eliminates DOP holes (with open sky) – RAIM* integrity checked everywhere, all the time • Eliminates RAIM holes (with open sky) – Phase ambiguity resolution for survey and machine control applications * Receiver Autonomous Integrity Monitoring Moscow Satellite Navigation Forum 2008 24

Important for Interoperability • Common Center Frequency – Like L 5 & E 5 a • Same Antenna Polarization • Common Signal Spectrum Essential (cost driver) Important (no time bias or filter issues) – Identical receiver time delay with common spectrum • Same coherent integration period for acquisition – Usually related to symbol rate – Different symbol rates may require separate search correlators for acquiring signals Desirable (ASIC gate count) Moscow Satellite Navigation Forum 2008 25

Other Interoperability Factors – System Time • System time offset may affect interoperability, depending on the circumstance • This is why system time offset parameters will be part of future GPS, Galileo, and QZSS messages – Permits use of only one or two extra satellites • Conversely, GPS and GLONASS receivers function well without a time offset message – Receivers compute and remember time offset, to high precision, if 2+3 or more satellites are in view • Time offset is a slowly changing solution variable • No impact with common differential corrections – From the same reference station or network Moscow Satellite Navigation Forum 2008 26

Other Interoperability Factors – Geodesy • Geodesy differences may affect interoperability, depending on the extent of the differences • Much progress in eliminating geodesy offsets – Continuing work is underway • Current GNSS geodesy models are so nearly equivalent that most users are not affected – Coordinate system differences are known and can be applied in the receiver software – Also, no impact with common differential corrections Moscow Satellite Navigation Forum 2008 27

GNSS Frequency Bands and Signals GPS M SBAS C/A P(Y) SBAS L 2 1227. 6 MHz L 5 1176. 45 MHz M C/A P(Y) L 1 1575. 42 MHz GLONASS Possible future signal E 5 a 1176. 45 MHz 1598. 06251605. 375 MHz 1242. 93751248. 625 MHz GALILEO E 6 1278. 75 MHz E 5 b 1207. 14 MHz L 1 1575. 42 MHz QZSS L 5 1176. 45 MHz Beidou/Compass ITU Filings Here L 5 1176. 45 MHz L 2 1227. 6 MHz ITU Filings Here L 2 1227. 6 MHz IRNSS Moscow Satellite Navigation Forum 2008 LEX 1278. 75 MHz ITU Filings Here E 6 1278. 75 MHz L 1 1575. 42 MHz ITU Filings Here L 1 1575. 42 MHz Beidou/Compass & IRNSS In S-band 28