Various kinds of GPS Satellite Signal

There are 3 kinds of signals which is owned by GPS :
Carriers
GPS satellites send signals on two frequencies. L1 1575.42 MHz by bringing the two status messages and pseudo-random code for the purpose of calculating the time. 1227.60 MHz L2 brings with menggunakaan precession more accurate due to military purposes. Power radio signals emitted only ranged from 20-50 Watts. This is classified as very low considering the distance between the GPS and satellite to 12,000 miles. The signal emitted by line of sight (LOS), can pass through clouds, glass but can not be solid objects like buildings, mountains.

Pseudo-Random Codes

GPS is used for the public to monitor the frequency of L1 on the UHF (Ultra High Frequency) 1575.42 MHz. L1 signal that is sent will have the patterns of a particular digital code known as pseudorandom. Transmit signal consists of two parts: the code Protected (P) and the Coarse / Acquisition (C / A). Code that was sent was also unique among the satellites, allowing each receiver to distinguish signals sent by one satellite with another satellite. Some code Protected (P) also exists a randomized, so as not to be accepted by ordinary GPS. The random signal is known as the Anti-spoofing, which is commonly used by GPS specifically for certain purposes such as military.

Navigation Message
There is a weak power frequency signal added to the L1 codes that gives information about satellite orbits, clock corectionnya and other system status.


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