GPS CALIBRATION SYSTEM AND MEHTOD FOR SPEEDMETER BASED ON GPS

摘要

According to an embodiment of the present invention, a GPS-based speedometer calibration system comprises: a GPS signal generation device capable of generating at least three virtual GPS signals; a GPS signal transmission device modulating the frequency of the GPS signals to include, in a carrier wave, the GPS signals received from the GPS signal generation device; a signal separation device copying the GPS signals transmitted from the GPS signal transmission device, and separating the same into first and second GPS signal groups; a reference measurement device calculating a standard speed value for a moving specific object by measuring a Doppler frequency through the first GPS signal group received from the signal separation device; an object-to-be calibrated measurement device calculating a measured speed value of the specific object by measuring a Doppler frequency through the second GPS signal group received from the signal separation device; and a control device controlling the operation of the GPS signal generation device, receiving the standard speed value and the measured speed value from the reference measurement device and the object-to-be calibrated measurement device, respectively, and outputting the same. The control device compares the standard speed value with the measured speed value, and outputs, as a measured error value of the object-to-be calibrated measurement device, a value obtained by subtracting the measured speed value from the standard speed value. Therefore, the GPS-based speedometer calibration system can correct an error value more accurately.