Doppler ambiguity analysis and suppression for LTE-based passive bistatic radars

摘要

In this study, we provide a detailed analysis of the frequency division duplex long term evolution downlink (FDD LTE DL) signal for passive bistatic radars that use the signal as an illuminator of opportunity. In particular, we analyze the cross-ambiguity function and illustrate its undesired deterministic peaks in the Doppler dimension due to the specific structure of the FDD LTE DL signal. A new adaptive mismatched filtering method is proposed for pre-processing the original reference signal to suppress these undesired deterministic peaks in the range-Doppler processing. The effectiveness of our proposed method is demonstrated via simulations following robustness analysis, showing that all undesired peaks are suppressed below ?40 dB, with only 1.7 dB reduction in the main peak.