多通道数字接收机的设计与实现

摘要

为了解决传统模拟中频接收机相位分辨率低等缺点,提出一种基于软件无线电的中频数字接收机技术.针对雷达信号的特点提出了脉宽匹配滤波器的设计方法.采用基于多相滤波的正交变换理论,以及基于脉宽匹配的数字滤波器方法完成了一种五通道中频数字接收机的设计.接收机利用五路高速A/D变换器对输入的模拟信号进行采样,然后将采样数据送入FPGA进行处理,最终完成了每两路信号相位差的提取.实验结果表明系统具有成本低、精度高、结构简单等特点,而且具有一定的工程应用价值.%In order to solve the shortcomings of low phase resolution of the traditional simulative intermediate frequency receiver, the technology of intermediate frequency digital receiver based on software radio was proposed. Aiming at the characteristics of radar signal the design method of pulse width matched filter was put forward. Using the orthogonal transform theory which based on multiphase filter and pulse width matching digital filter method, a design of five channel intermediate frequency digital receiver was completed. Receiver used five ways high-speed ADC to sample the input analog signals, then sent the sampling data to the FPGA for processing, eventually it completed the every two-channel signals phase extraction. Experimental results show that the system has the characteristics of low cost, high precision, simple structure and so on, and has certain value for engineering application.