相位比较器实现的VHDL程序，现有的C相结构。

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相位比较器的VHDL实现程序，现行的相位比较器结构往往十分复杂，难于实现。而在一些对精度要求不是很高的领域，简单灵活的相位比较算法有着广阔的市场。-Phase comparator realize the VHDL program, the existing structure of the phase comparator is often very complex and difficult to realize. In some of the precision of the field is not very high, simple and flexible algorithm for phase comparison with a broad market.