CHAPTER 11:  SPECIAL APPLICATIONS FOR NAVSTAR GPS

11.1  INTRODUCTION

Navstar GPS is a positioning system that will be a definite force enhancer in military

operations.  Since GPS will also be available to civilian users and has the potential to

enhance military operations other than weapon delivery, several special applica tions

for GPS have been developed.  This chapter will discuss four special applications

already developed to indicate the variety of GPS uses.  The four special applications

discussed are as follows:

1.

DGPS Applications

2.

GPS used as an attitude reference system

3.

Precise time and GPS

4.

Orbit determination using GPS

11.2  DGPS APPLICATIONS

11.2.1  Potential Uses of DGPS

DGPS can be used for a variety of applications.  Some of these applications will be

discussed in this chapter. 

Instrument approach

All weather helicopter operations

Narrow channel maritime operations

Reference Station for testing/calibration of navigation equipment

Surveying for mapping and positioning

Blind take off

11.2.1.1  Instrument Approach

Most established airfields have sufficient landing instrumentation, however, during

major conflicts, GPS can be used as an approach aid to temporary airfields. The GPS

PPS accuracies are adequate to provide non precision approach guidance to any

landing location in the world, providing the coordinates of the runway end are

accurately known.  The use of DGPS would allow even better accuracy and may allow

lower descent limits to a smaller landing area.  The DGPS system can be set up almost

immediately to provide very accurate guidance to any runway threshold.

11.2.1.2  All Weather Helicopter Operations

Helicopters are required to operate almost anywhere under all weather conditions, day

or night.  DGPS is used to give helicopters improved position and height information

when maneuvering close to the ground and in close proximity to obstacles.

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