GPS M码信号压制干扰样式效能分析

摘要

Aiming at the feature and superiority on anti-jamming of global position system (GPS) M code signal, in order to find an effective jamming mode for M code signal, the jamming efficiency of three types of typical blanket jamming, single frequency, band-limited Gaussian noise, and pseudo code with the same rate, are analyzed. In the analysis, the power spectral density change of GPS receiver cross-correlation filtering output is taken as the qualitative evaluation bases;the code tracking error and the ephemeris bit error rate (BER) are taken as the quantitative evaluation indexes. The influence process of jamming to evaluation factor and the oneness of each evaluation factor are derived theoretically by modeling M code signal receiving system. The simulation results show that single frequency jamming exhibits the best jamming effect while band-limited Gaussian noise jamming is the worst, the second comes pseudo code with the same rate jamming when the influence of sub-carrier modulation was eliminated. Considering the complexity of smart jamming implementation, it is suggested to choose the pseudo code with the same rate as M code signal jamming since single frequency jamming needs strict frequency setting and it is easily eliminated by frequency domain filtering.%针对GPS M码信号的特点和在抗干扰方面的优越性，为实现对其有效干扰，以接收机相关滤波输出功率谱变化情况作为定性评估依据，以码跟踪误差和星历误码率作为定量评估指标，对单频、带限高斯噪声和同速率伪码3种典型压制干扰样式的干扰效能进行分析。通过建立M码信号的接收系统模型，从理论上推导了干扰对各具体评估要素的影响过程以及各要素之间的统一性。仿真结果表明，单频干扰效果最好，消除副载波调制影响的同速率伪码干扰次之，带限高斯噪声干扰效果较差。考虑到单频干扰对干扰频偏设置的较高要求以及容易被接收机通过频域滤波而抑制掉的实际情况，结合实施灵巧干扰的难易程度，可选择同速率伪码干扰作为对M码信号的压制干扰样式。