量程自整定高精度频率测量的FPGA实现

FPGA implementation of auto span-switching high precision digital cymometer

数字频率计是一种应用十分广泛的电子测量仪表,针对宽频率范围被测信号频率测量应用需求,提出并实现了一种基于FPGA的自动量程切换高精度数字频率计的设计方法。通过构建测频控制器、闸门同步生成器、量程自动切换等模块,并采用Verilog HDL语言进行描述,运用自顶向下的数字系统设计方法实现了宽频率范围频率测量的量程自动切换。在Xilinx公司的XUPV5-LX110T开发板上进行了测试,给出了系统后仿真波形。结果表明目标系统能根据被测信号频率范围进行自动量程切换,实现高精度频率测量,测量精度不低于10-7,有效提高系统稳定性和抗电磁干扰能力。

Digital cymometer is widely used in the field of electronics measurement. Aim at the need of frequency measurement of those signals with wide frequency-band, this paper proposes an FPGA-based design method for automatic span-switching and high precision digital cymometer. The system controller, time-gate sync generator, span auto-switching and other modules are constructed and described by using Verilog HDL, which implements the automatic frequency-measurement of those signals with wideband. The proposed method is implemented on the Xilinx XUPV5-LX110T board and the post-simulation waveform is presented in this paper. The testing result shows that the proposed method can automatically switch span according to the signal＇s frequency and improves the system stability and the anti-interference ability.