GPS satellite signal is divided into L1 and L2, the frequency is 1575.42MHZ and 1228MHZ respectively, among them L1 is the open civilian signal, the signal is circular polarization. The signal strength is about -166DBM, which is a relatively weak signal. These characteristics determine the need to prepare a special antenna for GPS signal reception.
There are built-in and external ps antennas. For example, the GPS antenna of a mobile phone is built-in. You don’t see an antenna on the phone. Some mobile phones also support an external GPS antenna. Antenna socket. There are built-in and external gps modules. The gps module on the mobile phone is built-in. Some devices do not have a gps module, but an external gps module can be used to realize the star search function.