Abstract: The Global Navigation Satellite System (GNSS) plays a strategic role in positioning, navigation, and timing in infrastructure application. Given the characteristics of GNSS signals such as extremely low landing power and transparent civil code structure, civil satellite signals are extremely vulnerable to interference and spoofing attacks, which makes GNSS suffer from serious interference problems. In this paper, to address the problems of low detection probability and poor reliability of traditional SQM (signal quality monitoring) detection quantities, we propose a new type of SQM detection quantities without the carrier phase information of tracking loop. Then, the metric values are moving averaged to reduce the effect of abnormal fluctuation value on the false alarm probability. Besides, the statistical distribution characteristic of the proposed metric is derived. The computation threshold and measurement threshold without a priori information are set up. The proposed method can avoid the failure detection when the relative carrier phases of spoofing and authorized satellite navigation signal are integer multiples of π. The comparison experimental results based on the public database with real measured signals of TEXBAT (texas spoofing test battery) show that the proposed algorithm is able to detect spoofing attacks with better accuracy in a shorter time under different real signal scenarios. The research results are valuable for the development of anti-spoofing communication devices in the future to improve the detection performance effectively without making large-scale changes to the hardware structure of the receiver.