Electronic attack devices can interrupt a radar system by emitting jamming signals. This function typically depends on the support from electronic support measure (ESM) devices, which can capture and identify radar signals in the air. A radar system can avoid being interrupted by confusing adversarial ESM devices. In this article, at the background of colocated multiple-input multiple-output radar, we present an active antijamming method that aims at confusing adversarial ESM devices by masking radar signals with accompanying signals. Masking signals can be transmitted in either the pulsed mode or the periodic continuous-waveform mode. They can be either constant-modulus or with amplitude modulation. The masking signal will cover the radar signal in both time and frequency domains, in order to make adversarial ESM devices find it hard to determine whether an intercepted signal source is a spoofing device or an operating radar. We suppress the impact of masking signals on radar-matched filters, measured by the integrated sidelobe level and peak sidelobe level of their cross-correlation sidelobes, through optimization of masking signals. Masking signals whose chip duration is shorter than that of radar signals are considered for a lower cross-correlation sidelobe level. It is termed as the sequence spread spectrum method, and this method is found critical to obtain good cross-correlation sidelobes, as indicated in numerical results with several kinds of well-designed radar signals. In concerned simulation scenarios, a good masking signal tends to focus its power on frequency bands, where the radar signal power is low.

中文翻译：

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优化 MIMO 雷达信号掩蔽


电子攻击设备可以通过发射干扰信号来中断雷达系统。该功能通常依赖于电子支持测量（ESM）设备的支持，该设备可以捕获和识别空中的雷达信号。雷达系统可以避免被令人困惑的敌对 ESM 设备中断。在本文中，以共置多输入多输出雷达为背景，我们提出了一种主动抗干扰方法，旨在通过用伴随信号掩盖雷达信号来迷惑敌对ESM设备。掩蔽信号可以以脉冲模式或周期性连续波形模式传输。它们可以是恒模的，也可以是幅度调制的。掩蔽信号将在时域和频域上覆盖雷达信号，以使敌方ESM设备难以确定拦截的信号源是欺骗设备还是正在运行的雷达。我们通过优化掩蔽信号来抑制掩蔽信号对雷达匹配滤波器的影响，通过其互相关旁瓣的积分旁瓣电平和峰值旁瓣电平来测量。码片持续时间短于雷达信号的掩蔽信号被认为具有较低的互相关旁瓣水平。它被称为序列扩频方法，正如几种精心设计的雷达信号的数值结果所示，该方法对于获得良好的互相关旁瓣至关重要。在相关的仿真场景中，良好的掩蔽信号往往将其功率集中在雷达信号功率较低的频段上。