单脉冲脉内互补低距离旁瓣雷达波形设计

Intra-Pulse Complementary Radar Waveform Design with Low Pulse Compression Sidelobe Level

雷达脉冲压缩的距离旁瓣较高将会导致遮蔽效应的产生,已有的低旁瓣波形设计都是基于全脉冲相关进行处理。本文利用波形组合的方法进行波形设计,基于单脉冲脉内分段脉压信号处理方式和互补码自相关求和零旁瓣特征相结合,利用频域正交设计,将两个或多个互补序列调制至不同频点以子脉冲的形式分段合并为恒模单脉冲雷达波形。仿真试验表明,本文设计的单脉冲脉内互补低旁瓣波形脉压后的峰值旁瓣电平和积分旁瓣电平较低,分段脉压结合互补码零旁瓣特征的信号处理方式虽然会导致0.89 dB左右的信号处理增益损失和主瓣展宽,但却能够突破部分相位编码信号的峰值旁瓣电平下限。强弱目标场景仿真表明,与线性调频信号相比,本文提出的雷达波形不会导致强目标的副瓣对弱目标的遮掩。恒虚警检测仿真表明,在剔除强目标峰值后,本文所提波形对弱目标的检测概率要优于传统的线性调频信号。

For pulse-compression radar waveforms,higher range side lobes will result in the target masking effect.Low range sidelobe radar waveform design is an important research on radar waveform.The existing low-range sidelobe waveform designs are all based on full-pulse correlation.This paper uses the method of waveform combination to design the waveform.Based on the frequency-domain orthogonal design,two or more sub-pulses of complementary sequences are modulated to different frequency points and then combined into a constant-modulus monopulse radar waveform.Different from full-pulse matched filtering,this paper presents a single-pulse intra-pulse segmental pulse compression signal processing method,which makes full use of the autocorrelation characteristics of complementary codes.The simulation test shows that the peak sidelobe level and the integral sidelobe level of the designed waveform after pulse compression are low,and can even break through the lower limit of the peak sidelobe level of some phase-encoded signals,but there will be main-lobe broadening and 0.89 dB energy loss.Compared with the chirp signal,the radar waveform proposed in this paper does not cause the sidelobe of the strong target to mask the weak target.The constant false alarm detection simulation shows that the detection probability of the waveform in this paper is better than that of the chirp signal.