ILLUSTRATIONS

Figure

Page

1 1

Navstar GPS Major Segments...................................................................................................1 1

1 2

GPS Satellite Constellation........................................................................................................1 3

1 3

GPS Control Segment Locations...............................................................................................1 4

1 4

Monitor Station and Ground Antenna .......................................................................................1 5

1 5

The Navigation Message ...........................................................................................................1 8

1 6

Satellite Signal Modulation........................................................................................................1 9

1 7

GPS Signal Frequency Spectrum.............................................................................................1 10

1 8

Spread Spectrum Generation and Reconstruction ...................................................................1 11

1 9

Generic GPS Receiver Tracking System .................................................................................1 12

1 10 GPS Receiver Theory of Operation.........................................................................................1 16

2 1

Analog GPS Receiver Architecture ...........................................................................................2 7

2 2

Digital GPS Receiver Architecture ............................................................................................2 8

3 1

Dilution of Precision ..................................................................................................................3 4

3 2

Time To First Fix (TTFF).......................................................................................................3 12

4 1

Example of a Dedicated CDU ...................................................................................................4 3

4 2

Example of a Multifunction CDU..............................................................................................4 4

4 3

Example of a Data Loader System ............................................................................................4 6

4 4

Flight Instruments and TACAN.................................................................................................4 8

4 5

Flight Instruments and GPS.......................................................................................................4 9

5 1

FRPA Spiral Helix .....................................................................................................................5 3

5 2

FRPA Bifilar Helix.....................................................................................................................5 3

5 3

FRPA Crossed Monopoles........................................................................................................5 3

5 4

FRPA Ground Plane..................................................................................................................5 4

6 1

Satellite Global Visibility Profile ................................................................................................6 4

7 1

Aiding Options for a GPS Receiver...........................................................................................7 1

8 1

GPS Stand Alone Configuration ...............................................................................................8 3

8 2

GPS INS Aided Configuration..................................................................................................8 4

8 3

Configuration with Mission Computer/Databus Emulator.........................................................8 5

8 4

GPS in 1553 Databus Configuration..........................................................................................8 6

9 1

Simplified Diagram of Kalman Filter..........................................................................................9 3

9 2

Geometry for GPS Measurement ..............................................................................................9 8

9 3

Open Loop GPS/INS Aided Architecture...............................................................................9 12

9 4

Closed Loop GPS/INS Aided Architecture.............................................................................9 12

9 5

Open Loop Integrated GPS/INS Architecture ........................................................................9 13

9 6

Closed Loop Integrated GPS/INS Architecture......................................................................9 14

10 1 Typical Differential System Architecture .................................................................................10 1

10 2 Typical Reference Station........................................................................................................10 9

10 3 Typical UE Block Diagram....................................................................................................10 10

11 1 Interferometry Using GPS.......................................................................................................11 4

11 2 The Interrelationship of the Different Methods of Measuring

   and Defining Time ................................................................................................................11 8

11 3 Determination of GPS UTC (USNO) Time Difference.........................................................11 10

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