通道失配对GNSS阵列抗干扰性能的影响分析

卫星导航接收机极易受到电磁干扰的影响,基于阵列接收机的空时(频)抗干扰技术被证明是目前最有效的抗干扰手段。在工程实现时,阵列通道存在通道失配,本文以统计性能的评估方法评估了通道失配对阵列抗干扰性能的影响。研究结果表明,通道间群时延偏差和幅度失配是导致阵列抗干扰性能下降的主要因素,前者可通过增加空时滤波器阶数来消除影响,而后者对空时滤波器阶数不敏感,需要进行必要的校正。

Effect of channel mismatch on the anti-jamming performance of GNSS adaptive antenna arrays

Satellite navigation receivers are highly susceptible to electromagnetic interference, and array-based space-time or space-frequency adaptive processing has been proved to be the most effective anti-jamming method. In actual engineering implementation, the channel mismatch is inevitable. Thus in this paper, the impact of channel mismatch on the performance of GNSS antenna array was evaluated according to the statistical evaluation method. The results show that, group delay bias and amplitude mismatch between channels are the two main factors leading to the deterioration of anti-jamming performance. The influence of the former can be eliminated by increasing the number of taps of space-time filter, while the latter is not sensitive to the number of taps and the necessary calibration is required.