PURPOSE: To accurately evaluate the function and capacity of a receiver by comparing the position and speed data calculated by simulating the motion of a motion body with the results due to the GPS signals from the track data of a plurality of predetermined GPS satellites.

CONSTITUTION: When a GPS receiver 16 is tested, the first operation part 10 simulates the motion of a motion body such as a satellite to calculate the position and speed thereof within a real time and outputs the data thereof to the second operation part 12. The track data of a GPS satellite preliminarily stored in a memory part 13 are inputted to the operation part 12 and the delay quantity and Doppler shift due to the propagation of a radio wave are calculated on the basis of those data to be outputted to a signal generating circuit 14. A GPS signal is formed in the circuit 14 and the signals from a plurality of GPS satellites calculated in the same way are synthesized by a power synthesizer 15 to be outputted to the receiver 16. The receiver 16 measures the position and speed of the motion body from the inputted GPS signals and compares the same with the result of the first operation part to evaluate function and capacity.