Adaptive Signal Processing Method Using a Single-Element Dual-Polarized Antenna for GNSS Interference Mitigation

摘要

Due to their weak received power, Global Navigation Satellite Systems (GNSS) signals can be easily disrupted by radio frequency interference. Various GNSS signal processing techniques using single-antenna-based methods and antenna-array-based methods have been addressed in the literature to mitigate the interference, as well as to enhance the desired GNSS signals. However, single-antenna techniques do not successfully suppress wideband interference in general, and the computational complexity, as well as the large size and high cost of the antenna array, still remain as barriers to numerous applications. To obtain interference mitigation performance while reducing hardware complexity, the polarization diversity provided by single-element dual-polarized antennas has also been studied. However, to the best of the authors' knowledge, the previous works can mitigate only one source of interference at a time, or only interference with a certain polarization (e.g., linearly-polarized interference only). This paper proposes an adaptive signal processing method for a single-element dual-polarized antenna. Similar to spatial-temporal adaptive processing algorithms for antenna arrays, our method can mitigate one wideband interference signal in the spatial domain by exploiting polarization diversity while mitigating the narrowband interference in the frequency domain using finite impulse response (FIR) filters. We consider right-hand circularly polarized (RHCP), left-hand circularly polarized (LHCP), and linearly polarized (LP) interference signals, and it is shown that our method has the capability to simultaneously suppress one wideband and multiple narrowband interferences with any of the three polarizations (i.e., RHCP, LHCP, and LP). For a demonstration of our method, simulation is performed with one wideband and multiple narrowband interference signals, which have different polarizations, in the test scenario. Using the weight vector obtained by the proposed algorithm, the angle-frequency response, frequency responses with respect to the three polarizations, and signal-to-interference-plus-noise-ratio plots are presented.