An On-board Autonomous Detection Technology of carrier leakage on GNSS Signal

The performance of GNSS depends on the quality of navigation signal, which is of great importance to the position accuracy and integrity. With the abilities of immediate warning, low cost and less depending on ground station, the onboard Satellite Autonomous Integrity Monitoring (SAIM) becomes an indispensable technology of signal quality monitoring (SQM), or detection of evil waveforms. As a common anomaly of GNSS signal, Carrier leakage is usually identified by obvious peak uplift at carrier frequency point. This paper analyzes the causes of carrier leakage, and based on the traditional model, a more reasonable mathematical model is putted forward. When there exists carrier leakage, part of signal energy will be concentrated in the frequency point, which makes it possible to detect the carrier leakage by energy detection technique. So we present a novel carrier leakage detection arithmetic based on energy detection, and it shows very guiding significance for the on-board Satellite Autonomous Integrity Monitoring technology.