GPSP tracking receiver
The GPSP is a tracking system that uses the GPS constellation of satellites to determine the exact position of a transmitter.
Function
The GPSP supports precise orbit determination by the Doris system. It also helps to improve gravity field models and provides data for satellite positioning.
Principle
The GPSP receives dual-frequency navigation signals continuously and simultaneously from up to 12 GPS satellites (usually 8 are used). It uses these signals to acquire phase measurements accurate to about one millimeter and pseudo-range measurements accurate to about 10 centimeters.
Technical data
The onboard system consists of two independent receivers operating in cold redundancy, each with an omnidirectional antenna, low-noise amplifier, quartz oscillator, sampling converter, and a baseband digital processor communicating via the bus interface.
For more information see International GPS Services.
Past missions 
