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Simulation of Beidou signal quality degradation in marine navigation equipment testing

The working environment of marine navigation equipment is poor. Limited by factors such as volume, energy consumption and cost price, higher integration is adopted in hardware design and the number of components is reduced. In the process of equipment testing, the decline of Beidou navigation signal quality has a particularly important impact on equipment performance. The signal degradation will lead to the correlation peak distortion in receivers, which will induce large tracking errors and finally affect positioning, navigation, and timing (PNT) performance. The objective of this paper is to simulate and detect Beidou signal distortions. An offline analysis method is introduced to effectively assess the signal quality in multiple domains based on the software receiver processing. Compared to a previous multi-correlator method which detects “evil waveforms” (EWFs) through correlation peak symmetry tests in the receiver, it characterizes the pre-correlation signal quality more clearly and expressively.