A GNSS Interference Monitoring Method with Low False Alarm and Low Missed Detection Probability

Interference monitoring and analysis for GNSS frequency bands plays an important role in construction and development of satellite navigation systems, which can promote interference source locating, and has much benefit for system construction and the development of anti-jamming equipments. Due to high satellite orbits, GNSS signals reached the ground are very weak and submerged below the thermal noise, which makes it vulnerable to interference. Interference sources for satellite navigation system require only a small transmission power; however, a significant interference effect can be obtained. Therefore, a high sensitivity is needed by interference monitoring for satellite navigation system. The interference judgment threshold is close to thermal noise power, which often causes a higher probability of false alarm. It is very important to reduce the probability of false alarm at the same time to ensure high sensitivity. In this paper, a high sensitivity (low missed detection probability) and low false alarm interference monitoring method is proposed, a dual decision threshold is designed, thus the probability of false alarm can be effectively reduced at the same time of identifying interference accurately. The experimental results demonstrated the effectiveness of the algorithm.