数字接收机的硬件实现

Hardware Realization of a Digital Receiver

本文主要讨论一种基于软件无线电技术的中频多通道数字接收机的实现.在系统具体实现中,依据Nyquist欠采样理论,采用带通信号采样.将较高的中频变到较低的中频,它克服了传统接收机使用两个乘法器产生同相和正交信号所带来的两路特性不一致的问题.对经过采样信号的后期处理全部交给FPGA,用软件来实现.结果表明,系统具有成本低、精度高、结构简单等优良性能,可以满足实际需要.

The software radio made noticeable progress in recent years since putting forward for the first time by Jeo Mitola 1992. This article discussed the realization of the multicharmel digital receiver Based on Software Radio. Concrete while realizing in the system, Nyquist Band - pass Sampling was adopt. Higher intermediate frequency will become lower intemediate frequency, it has overcome the inconsistencies in phase produced by two multiplications used by traditional digital receiver. Signals sampled were given to FPGA on later stage where all dispoistions will be realized with the software. The result shows, the system has free performance such as lower costs , higher precision simple structure, can meet the actual demands.