干扰条件下基于互信息量准则的弹载雷达波形优化

弹载雷达发射波形设计在导弹制导系统中有着重要作用。为解决复杂电磁环境下，弹载雷达受到噪声、杂波和干扰影响导致目标探测性能降低的问题，基于互信息量（mutual information，MI）准则提出了一种新的同时存在噪声、杂波和电子干扰影响时的发射波形优化算法，通过拉格朗日乘子法得到最大化目标响应与雷达回波间互信息量的最优波形表达式，并利用一阶泰勒级数近似简化该表达式。仿真实验对比了不同杂波和压制干扰、不同发射能量约束下优化前后所获互信息量；结果表明，当平均功率限制为100 W时，相比于原始波形，采用优化信号情况下所获互信息量翻倍。优化发射波形能够通过优化信号的频域能量分布，主动避开干扰和杂波影响大的频率，使接收回波包含更多目标信息。

Waveform optimization for the missile-borne Radar under jamming using mutual information criterion

The transmitting waveform design of missile-borne radar plays an important role on missile guidance. To solve the problem of low target-detection performance when the missile-borne is affected by noise, clutter and jamming in the complex electromagnetic environment, a new waveform design algorithm based on the mutual information(MI) criterion is proposed. This algorithm maximizes the mutual information between the target ensemble and the received signal using Lagrangian multiplier method, then it is simplified by using Taylor series. The Simulation has compared the mutual information of optimized and original conditions under different clutters and blanket jamming with different power constraints. Simulation results indicate that, the optimized condition doubles the mutual information when compared to the original condition with 100watt average power constraints. The optimized waveform could lower the effect of jamming and clutter by redistributing the signal energy in the frequency domain, thus the received echoes contain more information of the target.