GPS C t ll ti M d i tiGPS Constellation, Modernization Plans and Policy

6th Space Conference of the AmericasP h M iPachuca, MexicoNovember 2010

Milo RobinsonSenior Advisor

National Coordination OfficeUnited States of America

Overview

• Introduction• Global Positioning System• Global Positioning System• Modernization Plans• U.S. Policy

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GPS enables a diverse array of applicationsSatellite

Operations

SatelliteOperation

sPower GridsPower Grids

Surveying & MappingSurveying & Mapping

Precision AgriculturePrecision Agriculture

G dsG ds

NextGenNextGenTransit

OperationsTransit

OperationsPrecision AgriculturePrecision Agriculture

Disease ControlDisease Control

TeleCommTeleCommIntelliDriveIntelliDrive

Trucking & Shipping

Trucking & ShippingPersonal

NavigationPersonal

Navigation

Oil ExplorationOil Exploration Fishing & BoatingFishing & Boating

GPS in Disaster Relief

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Restoring Infrastructure

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Overview

• Introduction• Global Positioning System• Global Positioning System• Modernization Plans• U.S. Policy

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The Global Positioning System

• Baseline 24+3 satellite constellation in medium earth orbitGl b l g 24 h d ll th diti• 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)– Precise (U.S. and Allied military)

• Three segments: – Space– Ground control– User equipment

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GPS Constellation Status

32 Operational Satellites(Baseline Constellation: 24+3)

• 11 Block IIA• 12 Block IIR

8 Bl k IIR M• 8 Block IIR-M– Transmitting new second civil signal– 1 GPS IIR-M in on-orbit testing

• 1 Block IIF– In Test and Checkout – First of 12 Boeing satellitesFirst of 12 Boeing satellites

• 3 additional satellites in residual status• Global GPS civil service performance

i i l icommitment met continuously since December 1993

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GPS Operational Control Segment (OCS)

S h i AFBS h i AFBEnglandEngland

AlaskaAlaska

Cape Cape CanaveralCanaveralHawaiiHawaii

KwajaleinKwajalein

Schriever AFB Schriever AFB ColoradoColorado S KoreaS Korea

BahrainBahrain

USNOUSNOVandenberg AFB Vandenberg AFB

CaliforniaCalifornia

AscensionAscension Diego GarciaDiego Garcia

Kwajalein Kwajalein

EcuadorEcuador

TahitiTahiti

AustraliaAustralia

S AfricaS AfricaArgentinaArgentina

NN

GroundAntenna MonitorStation

New New ZealandZealand

NGA Monitor Station

OCS Monitor StationMaster Control Station

Alternate Master Control Station

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Master Control Station (Schriever AFB)

Ground Antenna Future Monitor Station

Current GPS Accuracy

N/A7

met

ers

2001 SPS P f St d d

N/A N/A N/AN/ASignal-in-Space User Range Error is the difference between a GPS satellite’s navigation data (position and

5

6

m) Er

ror (

URE)

, m 2001 SPS Performance Standard(RMS over all SPS SIS URE)

navigation data (position and clock) and the truth, projected on the line-of-sight to the user

3

4

MS

SIS

URE

(me

User

Ran

ge 2008 SPS Performance Standard

(Worst of any SPS SIS URE)

1.61.2 1.1

0.91

2

RM

gnal

-in-S

pace

1.0

0

RM

S Si

g

Selective Availability (SA)

1990 1992 1994 1996 1997 2001 2004 2006 20092008

System accuracy exceeds published standard10

Overview

• Introduction• Global Positioning System• Global Positioning System• Modernization Plans• U.S. Policy

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GPS Modernization Program

Block IIA/IIR Block IIIBlock IIR-M, IIF

Increasing System Capabilities Increasing Defense / Civil Benefit

• Backward compatibility• 4th civil signal (L1C)• Increased accuracy• Increased anti-jam power

IIR-M: IIA/IIR capabilities plus• 2nd civil signal (L2C)•M-Code (L1M & L2M)

Basic GPS• Standard Service

– Single frequency (L1)Coarse acquisition (C/A) Increased anti jam power

• Assured availability• Navigation surety• Controlled integrity• Increased security

IIF: IIR-M capability plus• 3rd civil signal (L5)• Anti-jam flex power

– Coarse acquisition (C/A) code navigation

• Precise Service– Y-Code (L1Y & L2Y)

Y C d i i

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• Increased security• System survivability

– Y-Code navigation

Second Civil Signal (L2C)

• Designed to meet commercial needs– Higher accuracy via ionospheric correction– Expected to generate over $5 billion in user

productivity benefits

• Available since 2005• On 24 satellites by 2016

Benefits existing

Increases accuracy

gprofessional receivers

Supports miniaturization

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Increases accuracyfor consumers

Supports miniaturization, possible indoor use

Third Civil Signal (L5)

• Designed to meet demanding requirements for transport safetyq p y– Uses highly protected Aeronautical

Radionavigation Service (ARNS) band

• May also enable globalMay also enable global, centimeter-level accuracy using new techniques

• Opportunity for international• Opportunity for international interoperability

• Demonstration signal launched in 20082008

• 24 satellites by 2018

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Fourth Civil Signal (L1C)

• Designed with international partners for interoperability

• Modernized civil signal at L1 frequency– More robust navigation across a broad– More robust navigation across a broad

range of user applications– Improved performance in challenged

tracking environmentsUnder trees

– Original signal retained for backward compatibility

• Launches with GPS III in 2014• On 24 satellites by ~2021

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Inside cities

Overview

• Introduction• Global Positioning System• Global Positioning System• Modernization Plans• U.S. Policy

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U.S. Policy History

• 1978: First GPS satellite launched

• 1983: U S President offers free civilian• 1983: U.S. President offers free civilian access to GPS

• 1996: U S policy establishes joint1996: 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 Space-Based PNT Policy

• 2007: Selective Availability removed from GPS III satellites

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• 2010: U.S. President issues new National Space Policy

Latest U.S. Policy

• Provide continuous worldwide access for peaceful uses, free of direct user charges

• Encourage compatibility and interoperability with foreign GNSS services

• Operate and maintain constellation to satisfy civil and national security needs– Foreign PNT may be used to strengthen resiliencyForeign PNT may be used to strengthen resiliency

• Invest in domestic capabilities and support international activities to detect, mitigate and increase resiliency to harmful interference

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National Space-Based PNT Organization

WHITE HOUSEDefense

ADVISORY BOARD

NATIONALEXECUTIVE COMMITTEEFOR SPACE-BASED PNT

Transportation

State

InteriorSponsor: NASAExecutive Steering Group

Co-Chairs: Defense, Transportation

Interior

Agriculture

Commerce

NATIONAL COORDINATION OFFICE

Host: Commerce

Homeland Security

Joint Chiefs of Staff

NASA

GPS International Working Group

Engineering Forum Ad Hoc

NASA

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Working GroupChair: State

Co-Chairs: Defense, Transportation

Working Groups

Summary

• GPS performance is better than ever and will continue to improvecontinue to improve– Augmentations enable even higher performance– New civil GPS signal available nowNew civil GPS signal available now– Many additional upgrades scheduled

• U.S. policy encourages worldwide use of civil GPSU.S. policy encourages worldwide use of civil GPS and augmentations

• International cooperation is a priority– Compatibility and interoperability are critical

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For Additional Information…

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GPS.gov PNT.gov

Contact Information

Milo RobinsonSenior Advisor

U.S. National Coordination OfficeSpace-Based Positioning, Navigation and Timing

1401 C tit ti A N W1401 Constitution Ave, N.W.Washington, D.C. 20230-0001

Ph: (202) 482-0019 Milo.Robinson@pnt.gov

This presentation and other GPS information:www.pnt.gov

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