波形捷变二相编码信号产生与处理系统设计及实现

The Design and Implementation of Biphase coded singnal Generation and Processing System with Waveform Agility

本文以优化产生的二相编码信号为基础,应用超大规模集成器件,设计并实现了大压缩比二相编码信号的产生和数字处理系统。该系统处理190位、127位和63位三种典型码长,并具有处理190位以下任意码长信号的通用能力;系统兼有软限幅和硬限幅二种信号处理工作方式,供雷达操纵员根据目标环境条件灵活选用;系统既可采用码组波形捷变,实现MTI与波形捷变和频率捷变兼容;也可采用脉间波形捷变加非相参积累方式工作.本系统产生带有加性高斯噪声、子脉冲宽为0.3μs的模拟回波,在不同的多普勒频移(0～10kHz)下,测试了脉冲压缩系统的输出主副比及输出信噪比。在没有采用旁瓣抑制加权网络情况下,三位软限幅190位脉冲压缩输出主副比值,在f_d=0时为26.8dB,当f_d=8kHz时为21.6dB,满足了低空中近程监视雷达的工作要求。

This paper presents the design and implementation of the biphase coded signal generation andprocessing system with large pulse compression rate based on optimized biphase coded sequences and LSIdevices. The system can process the typical biphase code lengthes of 190, 127, 63 bit, and any other lengthen lessthan 190 bit. It provides two kind of pulse compression processing methods for radar operator according to tar-get environment(hard-limited or soft-limited). The system not only can adopt group- to- group waveform agili-ty compatible with MTI, but also can work in pulse-to- pulse waveform agility with non-coherent integration.When the subpulse width is 0.3μs and the return waveform is with Doppler frequeney (f_d =0 -10kHz), the sys-tem's output ratio of mainlobe to sidelobe [RMS] and output ratio of peek signal to noise [SNR] are measured.When f_d=0kHz, 3 bit soft-limited pulse compression output RMS is 26.8 dB in the condition of no weightingnetwork. When f_d=0, RMS is 26.8 dB; when f_d=8kHz. RMS is 21.6dB. This performances can meet the needsof low altitude surveillance radars.