GPS receivers are classified into different types based on their purposes, frequency, and channel.
A. For purposes
1. Aviation GPS Receiver: Mainly used in mobile vehicle aviation. Indicates the locations and speed of the moving carrier in real time. Psychologically measured with C/A number, so its unique positioning is less accurate, which is about +-25MM. If you are affected by SA, the differences can be +-100 MM. The GPS type of receiver is less expensive and widely used in various industries.
2. Terrestrial GPS Receiver: It is mainly used in precise measurement of terrain and engineering. It uses the value of the carrier phase to measure the relative position, so the result is accurate. The receiver is built in a complicated way, so the price is higher.
3. Time Transfer GPS Receiver: Transfer time by high-precision satellite. It is usually used in the observatory and wireless communication.
B. By frequency
1. Single channel GPS receiver: It only receives L1 carrier wave signal and positions by carrier phase value. It cannot remove the effect of ionosphere delay, so it is only applicable for ultra-short baseline precision position less than 15KM.
2. Dual Channel GPS Receiver: It can receive L1 and L2 carrier signals. With its differences from the ionosphere delays, the electromagnetic wave signal delay caused by the ionosphere can be eliminated. Therefore, it can be used in precision position for thousands of kilometers.
C. By channels: GPS receivers can receive signals transmitted from multiple GPS satellites at the same time. It uses a single antenna channel to separate received signals and track, manage and measure individual satellites. The channels are divided into multi-channel receiver, serial channel receiver, and multi-channel receiver.