双通道带通采样和多相滤波的微波引信信号侦察接收机

Study on Double Channel Sampling and Polyphase Filtering Based Reconnaissance Receiver of Fuze Signal

用于侦察无线电引信信号的数字侦察接收机必须具备以全概率截获宽频带内多个引信信号并进行近实时处理的能力,以此为目标设计了一种无线电引信侦察接收机的数字化方案。针对带通采样存在着频率覆盖盲区的问题,提出了宽带中频信号双通道带通采样的方法,通过增加一个采样通道既解决了传统处理盲区方法中设计复杂采样时钟电路、高矩形系数滤波器的困难,还缓解了后续DSP处理压力。为处理双通道采样带来的冗余数据并进一步解决实时性问题,推导出了一种更实用的基于实信号多相滤波的数字信道化方法。最后进行了带通采样、数字信道化和冗余数据剔除和FFT测频的功能仿真,结果证明方案功能正确,并具有很强的去宽带加性白噪声的能力。

Digital receiver for radio fuze signal reconnaissance must have the ability of intercepting several signals which arrive simultaneously in a wide band and processing them synchronously. Taking this as a cause, the paper designs a method for digitizing reconnaissance receiver. Double channel bandpass sampling method for wide band IF signal is presented to settle the problem of blind zone, which exchanges one more sampling channel for simplification of clock circuit and band pass filter. As a practical reconnaissance receiver, real-time processing performance must be considered. Digital ehannelizing method lays the base of parallel processing by multi DSP chips and discarding of the redundant data resulting from double channel bandpass sampling. By analyzing present methods for digital channeling, a novel digital ehannelizing method based on polyphase filter technique is demonstrated, which is more suitable for processing discrete real signals. Functional simulation is implemented in the end, the results show the eorreclness and excellent denoising capability in AWGN channel of proposed method.