Principals of Operation
6 -2
6.1.2
GPS System
The
NAVSTAR,
(
N
avigation
S
atellite
T
iming
A
nd
R
anging), GPS, (
G
lobal
P
ositioning
S
ystem) is a satellite based navigation system offering precision navigation capability.
The system was originally designed for military use, funded and controlled by the U.S.
Department of Defense. Civilian access has been permitted to specific parts of the GPS.
GPS offers a number of features making it attractive for use in aircraft navigation.
Civilian users can expect a position accuracy of 100 m or better in three dimensions. The
GPS signal is available 24 hours per day throughout the world and in all weather
conditions. GPS offers resistance to intentional (jamming) and unintentional interference.
The equipment necessary to receive and process GPS signals is affordable and reliable
and does not require atomic clocks or antenna arrays. For the GPS user, the system is
passive and requires a receiver only, without the requirement to transmit.
GPS determines the position of the user by triangulation. By knowing the position of the
satellite and the distance from the satellite, combinations of satellites can be used to
determine the exact position of the receiver. The fundamental means for GPS to
determine distance is the use of time. Distance is computed by using accurate time
standards and by measuring changes in time.
The GPS System is comprised of three segments:
•
Space Segment
•
Control Segment
•
User Segment
Fig. 6-1 GPS System Segments
Spa ce S egment
User S egm ent
Co ntrol Se gm ent
Fr om Satel lites
L1 Carr ier S ignals
-
time p ulses
-
ep hem er is
-
al manac
-
satelli te health
-
date, time
-
establi shed ephemeri s
-
cal cu lated alm an acs
-
satell ite health
-
tim e co rrectio ns
From The
Gro und S tati on
Содержание 87339
Страница 1: ...GPSG 1000 GPS Galileo Positional Simulator Operation Manual...
Страница 4: ...ii THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 6: ...iv THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 12: ...x THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 24: ...iv THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 26: ...ii THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 117: ...Testing 5 18 THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 127: ...Principals of Operation 6 10 Fig 6 12 GPS Code Correlation Process Fig 6 13 GPS Nav Data Recover by Moduo 2 Addition...
Страница 157: ...Principals of Operation 7 6 THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 161: ...A 4 THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 167: ...B 6 THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 187: ...E 6 The Simulation will run until the end of the Trajectory File Figure E 10 Fig E 10 Trajectory Simulation Complete...
Страница 189: ...F 2 THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 191: ...G 2 THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 193: ...H 2 THIS PAGE INTENTIONALLY LEFT BLANK...
Страница 195: ...I 2 THIS PAGE INTENTIONALLY LEFT BLANK...