应用于硅微谐振式传感器的等精度频率计设计

针对传统频率测量中存在的弊端,利用等精度测频原理,采用现场可编程门阵列(FPGA)设计实现了等精度频率计。通过FPGA对同步门的控制,使被测信号和标准信号在闸门时间内同步,消除了量化误差,提高了测量精度,实现了在整个测试频段内测量精度不随被测信号频率的高低而发生变化,即实现了等精度测量。实验证明:采用该频率计测量标准信号频率的相对误差数量级为10-6,测量谐振式传感器在温漂下的输出频率的变化稳定在±1 Hz,而且实现了谐振式传感器在红外辐射下频率的动态跟踪。

Design of equal precision frequency meter applied to silicon micro-resonant sensor

Aiming at the disadvantages of traditional frequency measurement,using equal precision frequency measurement principle,adopting field programmable gate array （FPGA）,design and achieve equal precision frequency meter.The measured signal and standard signal in the gate time are synchronized by controlling the synchronous gate using FPGA eliminate quantization errors and improve measurement precision which doesn＇t change with the frequency of the measured signal in the whole measurement frequency segment,that means equal precision measurement is realized.Experimental results show that the order of magnitude of relative errors by measuring standard signals frequence adopting the designed frequency meter is 10-6,and change of output frequency of resonant sensors is stablized in ± 1 Hz under the condition of temperature drifts,and dynamic frequency tracking under the infrared radiation is also implemented.