基于非匹配滤波的SAR通信一体化技术

SAR-communication integration technology under the framework of unmatched filtering

一体化波形设计是雷达通信一体化技术实现的关键,正交频分复用(OFDM)信号更是被视为最具应用潜力的一体化波形信号。然而,OFDM一体化信号在实际应用中存在如下问题:在匹配滤波框架下,OFDM一体化信号中包含的通信信号导致二维模糊函数出现高旁瓣和伪峰,影响合成孔径雷达(SAR)成像性能;OFDM一体化信号具有较高的峰均功率比(PAPR)值,无法充分发挥功放的线性放大性能,进而影响探测距离和通信性能。针对上述问题,将基于循环前缀的非匹配滤波成像算法应用到一体化信号处理中,同时提出基于离散傅里叶变换预编码的一体化信号设计方法,消除通信信号对成像性能的影响,并将信号的PAPR值控制在可接受范围内,实现了SAR成像和通信性能的良好兼容。最后通过实验证明了所提方法的有效性。

Integrated waveform design is the key to the realization of radar communication integration technology.Orthogonal frequency division multiplexing(OFDM)signal is regarded as the most potentially integrated waveform signal.However,the OFDM integrated signal has the following problems in practical application:under the framework of matched filtering,the communication signals contained in the OFDM integrated signal lead to high sidelobes and pseudo peaks in the two-dimensional fuzzy function,which affects the performance of synthetic aperture radar(SAR)imaging.OFDM integrated signal has a high peak-to average power ratio(PAPR),which can not give full play to the linear amplification performance of the power amplifier,and then affect the detection range and communication performance.Aiming at the above problems,this paper applies the CP(cyclic prefix)-based unmatched filter imaging algorithm to integrated signal processing and proposes an integrated signal design method based on discrete fourier transform(DFT)precoding to eliminate the influence of communication signals on imaging performance.The PAPR of the signal is controlled within an acceptable range to achieve good compatibility between SAR imaging and communication performance.Finally,the effectiveness of the proposed method is proved by experiments.