School of Computer and Information Engineering, Harbin University of Commerce, Harbin, Heilongjiang, China.
College of Automation, Harbin Engineering University, Harbin, Heilongjiang, China.
PLoS One. 2022 Apr 21;17(4):e0267216. doi: 10.1371/journal.pone.0267216. eCollection 2022.
In urban and other complex environments, satellite navigation signals are vulnerable to multipath interference, especially medium- and short-delay multipath interference, which seriously affects the positioning accuracy. Aiming at the problem that the effect of traditional methods on medium and short multipath suppression is not obvious and it is difficult to accurately estimate the direction of arrival (DOA) when beamforming is used, a multipath suppression scheme based on a postcorrelation and independent component analysis (ICA) algorithm is proposed in this paper. First, the satellite navigation signal on each array element is despread and demodulated by postcorrelation technology to improve the signal-to-noise ratio (SNR), and then the direct signal component is directly extracted by the ICA algorithm to filter the noise while suppressing the multipath interference. Simulation results show that this method can effectively suppress medium and short multipath interference when the SNR of satellite navigation signals is as low as -30 dB, significantly improve the SNR of navigation messages and reduce the bit error rate, which provides a new solution for global navigation satellite system (GNSS) multipath suppression.
在城市和其他复杂环境中，卫星导航信号容易受到多径干扰，尤其是中短延时多径干扰，这严重影响了定位精度。针对传统方法对中短多径抑制效果不明显且波束形成时难以准确估计到达方向（DOA）的问题，本文提出了一种基于后相关和独立分量分析（ICA）算法的多径抑制方案。首先，通过后相关技术对每个阵列元素上的卫星导航信号进行解扩和解调，以提高信噪比（SNR），然后通过 ICA 算法直接提取直达信号分量，在抑制多径干扰的同时滤除噪声。仿真结果表明，该方法在卫星导航信号 SNR 低至-30dB 时，能有效抑制中短多径干扰，显著提高导航消息的 SNR，降低误码率，为全球导航卫星系统（GNSS）多径抑制提供了新的解决方案。
