Doppler shift is one of the basic measurements of GPS receiver, and the correctness and precision of its solution will directly affect the accuracy and integrity of GPS solution.In GPS spoofing, the synchronization of Doppler shift also has a direct impact on the success rate of spoofing and the complexity of identification.Derived from the formula, Doppler shift depends on the relative geometric distribution of the receiving terminal and the transceiver.The compensation cycle of the decoy device also has influence on the recognition complexity of the decoy process.The simulation analysis shows that, the relative geometric distribution of the GPS spoofing device and its compensation cycle for Doppler shift deviation determine the recognition complexity of the GPS decoy signal generated by the device.It also provides a new method to recognize the GPS spoofing signal from the viewpoint of Doppler shift.