スプーフィング検知に向けたMUSIC法による信号到来方向推定

抄録

GNSS signals are weak and can easily be affected by radio interference. Also, since the signal format is open to the public, the signal can be created easily. Thus, a fake signal (spoofing signal) imitating a satellite signal may be generated and transmitted. As the signal has the same structure as the satellite signal, it is difficult for general receivers to distinguish them. However, the direction in which a spoofing signal arrives is usually different from that in which the satellite signal does. The purpose of this research is to calculate the direction of arrival (DOA) by using an array antenna and to determine whether the received signals are spoofing signals or not. The MUSIC algorithm can estimate the DOA with high accuracy, but this algorithm can be applied only when the number of arriving signals is less than that of antenna elements. Consequently, it is usually difficult to apply it to the satellite signals. Therefore, in this research, we proposed the MUSIC algorithm based on “despreading” of the satellite signals and verified the effectiveness of this method. As a results of experiment, the spoofing signal was detected by estimating the DOA of the received signals.