基于FPGA移相倍频方式的频率计设计与实现

The Design And Implementation Of Frequency Meter Based On FPGA With Phase Shift And Frequency Multiplication

FPGA给现代电子设计带来了极大的方便和灵活性,通过FPGA实现的数字频率计精度高,电路简单,实现方便。本文通过等精度测频频率计的设计与改进,提出如何在低成本FPGA上移相倍频获得等效1G Hz时钟,并降低相移误差的方法,同时通过仿真验证了方案的可行性,并给出了以限压放大为核心思想的硬件电路实现方法。

The implementation of digital frequency meter by FPGA has many advantages like high precision,simple circuit and easy to implement. In this paper,through the design and improvement of equal precision frequency measure meter,put forward how to get equivalent 1G Hz clock with phase shift and frequency multiplication in low cost FPGA,and reduce the method of phase shift error,at the same time,the feasibility of the scheme is validated by simulation. Also,give out a voltage limiting amplifier as the core thought of hardware circuit realization method.