GPS Status and Modernization

1
GPS Status and Modernization

• Munich Satellite Navigation Summit
• Munich, Germany
• 20 Feb 2008

Lt Col Harold Martin, US Air Force PNT Command
Lead Air Force Space Command
This briefing is for information only.  No US
Government commitment to sell, loan, lease,
co-develop or co-produce defense articles or
provide defense services is implied or intended.
2
Overview

• GPS Status
• Recent Modernization Improvements
• The Future
• Summary

3
GPS Serving the World

• Constellation the largest ever- 30 Healthy
  Satellites
• 13 Block IIA
• 12 Block IIR
• 5 Block IIR-M
• 31st satellite, SVN 23, still has a good clock
  AF working to see if it can be set healthy to
  achieve 31 healthy satellite constellation for
  first time ever
• Most Recent Launch
• IIR-18(M) 5th modernized SV
• Launched Wednesday, 20 Dec 07
• SVN 57, PRN 29, slot C1
• Set healthy on 2 Jan 08
• Next Launches
• IIR-19(M) Mar 08
• IIR-20(M) Jun 08 L5 demo payload
• IIR-21(M) - Sep 08
• IIF-1 launch in Spring 09

4
GPS Spectrum
Block IIA 1990
Block IIR 1997
Previous
since Dec 2005 (5 SVs)
Block IIR-M, 2005
Planned
Block IIF, 2009
Block III, 2014
(artists concept)
ARNS Band RNSS Band
ARNS Band
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GPS Status Serving the World

• Performance Our best ever accuracy
• Current Performance

Average URE from 30 GPS SVs 0.51 m
Source JPL 2/10/2008
6
GPS Status Serving the World

• Recent Modernization Improvements
• Launched 5th of 8 Block IIR-M satellites
• Architecture Evolution Plan transition to a new
  Command and Control System at 2 SOPS for
  day-to-day operations
• Launch, Anomaly and Disposal Operations (LADO) -
  transitioned from 1 SOPS to 2 SOPS

7
Recent Modernization Improvements

• 5 Block IIR-M Satellites on orbit now
• Second Civilian Signal, L2C
• L2C provides increased accuracy for civilian
  receivers applications from precision farming to
  construction surveying
• 5th satellite means more L2C coverage around the
  globe
• Dual frequency receivers reduce ionospheric
  errors
• Better performing atomic clocks than IIA
• IIR-M 20 will fly a demonstration payload with an
  L5 signal

8
Recent Modernization Improvements

• Architecture Evolution Plan (AEP)
• New Master Control Station operational Sep 14,
  2007
• Modern distributed system replaced 1970s era
  mainframe
• New Alternate Master Control Station at
  Vandenberg AFB, CA
• Increased capacity to monitor satellites
• Utilizes dedicated Monitor Stations and NGA
  Monitor Stations to allow increased monitoring of
  GPS signals
• Increased worldwide coverage to 100 (was 96.4)
  and have 99.8 of world double covered
• Utilizes dedicated GPS Ground Antennas and allows
  use of 8 Air Force Satellite Control Network
  remote sites for increased commanding capability
• Increased worldwide commanding capability daily
  from 92.7 of the time to 94.5 while providing
  nearly double the backup capability

9
Recent Modernization Improvements

• Launch, Anomaly and Disposal Operations (LADO)
• Transitioned capability from 1 SOPS to 2 SOPS -
  centralizes GPS operations into a single unit
• Replaces 90s mainframe based system with
  increased use of modern distributed technology
  with electronic technical orders while decreasing
  the maintenance burden
• Used for launch of IIRM-17 on Oct 17, 2007 and
  IIRM-18 on Dec 20, 2007

10
The Future of GPS
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Future of GPS Block IIF Satellites

• PPS Signals L1-L2 P(Y), L1-L2 M-code
• SPS Signals L1 C/A, L2C, and L5
• L5 will provide second civil unique frequency in
  protected band
• Program Status
• SV1 in qualification tests
• Delivery to Cape Dec 08
• First launch 2009

• Program Description
• 2 Rb 1 Cs clocks
• 12 year design life
• Launch Atlas V or Delta IV
• Satellite launch weight 3720 lbs

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Future of GPS Block III Satellites

• New L1C civil signal interoperable with
  Galileo/QZSS
• Aggressive Capability Insertion Program to mature
  capabilities
• Directional crosslink demo by IIIA baselined on
  IIIB
• High Power Spot Beam demo by IIIB baselined on
  IIIC
• Provides 20dB (100Xs) greater M-code power
• Program Status
• Implementing Block approach to incrementally
  respond to warfighter capability requirements
  reduces risk
• Contract in Source Selection, expect award Spring
  08

• Program Description
• GPS IIIA includes all GPS IIR-M/IIF capabilities,
  plus
• Enhanced earth coverage M-code power (10x)
  enables improved operations in jammed austere
  environments
• GPS III guarantees 4x better User Range Error
  than IIF
• GPS signal-in-space improves from lt3m to lt1m
• GPS III Integrity guarantee supports
  safety-of-life applications
• Probability of Misleading Signal-in-space
  Information (MSI) lt0.0001/hr (Threshold)

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The Future of GPS New C2 System

• Next Generation Operational Control Segment (OCX)
• Enables modernized messaging
• Controls more capable GPS constellation
• Monitors all GPS signals
• Two development contracts awarded 21 Nov 07
• Air Force Space Command (AFSPC) is standing up a
  Community of Interest (COI) to implement
  net-centric operations using OCX
• GPS COI is a forum for users to recommend the
  data and services that should accessible from the
  global information grid (GIG)

14
The Future of GPS User Equipment

• Comm/Nav/Network Fusion
• Benefit in comm/nav user equipment integration
• Better accuracy, reduced time uncertainty, data
  stripping, network interference
  detection/location
• A variety of approaches to comm/nav integration
  exist today and should be studied further
• Additional investment and prototyping is required
• Chip Scale Atomic Clocks
• Software defined receiver

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Summary

• Largest constellation in history with best
  accuracy ever
• Modernized Command and Control System allows more
  signal monitoring and quicker satellite
  commanding than ever before
• And were continuing to modernize and improve GPS
  even more!

GPS Serving the World as the Gold Standard in
Space Based Navigation