Study on the Influence of Channel’s Non-Ideal Characteristic on Pseudo-Code Measurement Bias for GNSS Receiver

GNSS has been widely used in civilian and military areas due to its high precision. However, the channel’s non-ideal characteristic may introduce pseudo-code measurement bias to degrade positioning precision. There are few theoretical analyses for interpreting why the channel’s non-ideal characteristic may introduce pseudo-code measurement bias and what kind of channels will not introduce pseudo-code measurement bias. We have conducted a systematical study on the above issues. Firstly, we established an analysis model for interpreting the channel’ non-ideal characteristic’s influence on pseudo-code measurement bias. Based on the analysis model, we proposed four sufficient conditions for unbiased pseudo-code measurement. Secondly, we applied the analysis model to typical channels, i.e. sine type group delay channel, frequency-domain anti-jamming channel and space-domain anti-jamming channel, to evaluate the channel’s influence on pseudo-code measurement bias. Finally, we conducted simulations to evaluate the theoretical analysis’ correctness. Results show that these typical channels do not introduce pseudo-code measurement bias, which are consistent with theoretical analysis. As a result, the correctness of the proposed four sufficient conditions is verified so that the proposed four sufficient conditions can be used to guide the design of unbiased pseudo-code measurement channel. Keywords: Channel characteristic, pseudo-code measurement bias, GNSS receiver, non-ideal