资料为matlab实现的DDC功能，即数字下变频。数字下变频是软件无线电中的关键技术，文件可用matlab打开，直接可以跑出波形。-this is the code of DDC(digital down converter) on matlab,DDC is a key technology of SDR,this file can be opened by matlab，and you will get the simulation waveform directly.

这是用VHDL语言写的数字下变频模块，包含整个工程文件，数字下变频是软件无线电中的关键技术，可以直接用Quartus II打开。-this is a module of DDC(Digital Down Converter) with VHDL, it includes the whole project,you can open it with Quartus II directly.