GPS satellite transmits carrier signals with two frequencies, namely L1 carrier with a frequency of 1575.42MHz and L2 carrier with a frequency of 1227.60Mhz. Their frequencies are 154 times and 120 times of the basic frequency of 10.23MHz, and their wavelengths are 19.03cm and 24.42cm, respectively. A variety of signals are modulated on L1 and L2 respectively. These signals mainly include:

　　C/A code

　　C/A code is also known as coarse capture code, which is modulated on L1 carrier and is a 1MHz pseudo-random noise code (PRN code) with a code length of 1023 bits (period of 1ms). Since each satellite has A different C/A code, we often use their PRN number to distinguish them. C/A code is one of the main signals used by ordinary users to determine the distance between the station and the satellite.

　　P code

　　P code is also known as fine code, it is modulated on L1 and L2 carrier, is 10MHz pseudo-random noise code, its period is seven days. In the implementation of AS, P code and W code are added mode-two to generate a secret Y code. At this time, ordinary users cannot use P code for navigation and positioning.

　　Y code

　　See P code.

Read recommendations:

GPS Tracker wholesaler

simple gps tracking manufacture

10000mAh Magnetic Asset GPS Tracker

Review of GPS development in the past ten years

gps tracker purchase points?