滤波器阶数对导航接收机时域抗干扰的影响分析

滤波器阶数是影响卫星导航接收机时域自适应抗干扰性能和计算复杂度的核心参数。为了解决当前阶数选取严重依赖工程经验而影响分析不足的问题，分析了滤波器阶数对导航接收机时域自适应抗干扰性能的影响，可为导航接收机低复杂度时域抗干扰的研究提供理论支撑。该分析面向不同干扰环境，分别以滤波器幅频响应和信号载噪比为评估指标，并通过仿真实验和实测对传统最小均方算法和改进型最小均方算法进行验证，提出了一种基于数字滤波器设计的自适应最优滤波器阶数的设计方法。实验数据分析表明，通过适当提升滤波器长度，可以有效提升时域自适应滤波器的抗干扰性能；在实际应用中，可根据实际抗干扰需求，对滤波器阶数进行优化设计。

Influence analysis of filter order on time-domain interference suppression of navigation receiver

Filter order is the core parameter affecting the time-domain adaptive anti-jamming performance and the computational complexity of satellite navigation receivers. In order to solve the problem that the current order selection is heavily dependent on engineering experience and the impact of the analysis is insufficient, the impact of the filter order on the time-domain adaptive anti-jamming performance of navigation receivers was analyzed, providing theoretical research for low-complexity time-domain anti-jamming. The analysis was oriented to different interference environments. The filter amplitude-frequency response and the signal carrier-to-noise ratio were used as evaluation indicators. The simulation experiments and practical tests verified the traditional LMS(least mean square) algorithm and the improved LMS algorithm. Finally, an adaptive design method for optimal filter order based on digital filter was proposed. Experimental data analysis shows that the anti-interference performance of the time-domain adaptive filter can be effectively improved by appropriately increasing the filter length. In practical applications, the filter order can be optimized by constraining the carrier-to-noise ratio loss.