# Presentation: 582947

## 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.**** **

## Overview

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

## 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) – 5****th**** 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**

## GPS  – Spectrum

***ARNS Band*****                               *****RNSS Band*****                             *****ARNS Band***** **

- Block IIA
- 1990

- Block III, 2014

- Block IIR-M, 2005

- Block IIF, 2009

**since Dec 2005**
**(5 SVs)**

- (artist’s concept)

**Planned**

** ****Previous**

- Block IIR
- 1997

## GPS Status – Serving the World

**Performance – Our best ever accuracy**
**Current Performance **

**Source: JPL 2/10/2008**

**Average URE from 30 GPS SVs: 0.51 m**

## GPS Status – Serving the World

**Recent Modernization Improvements:**
**Launched 5****th**** 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**

## 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**
**5****th**** 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**

## Recent Modernization Improvements

**Architecture Evolution Plan (AEP)**
**New Master Control Station operational Sep 14, 2007**
**Modern distributed system replaced 1970’s 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**

## 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 90’s 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**

## The Future of GPS

## Future of GPS – Block IIF Satellites

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

**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**

## Future of GPS – Block III Satellites

_**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 <3m to <1m**
**GPS III Integrity guarantee supports safety-of-life applications**
**Probability of Misleading Signal-in-space Information (MSI) <0.0001/hr (Threshold)**

**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**

## 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)**

## 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**

## 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 we’re continuing to modernize and improve GPS even more!**

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