Abstract：The effect of noise to frequency measurements on the condition of lowSNR is studied, on the basis of multi-cycle synchronization frequency measurement, method of an multi-multi-cycle synchronization frequency measurement is put forward and the formula of frequency measurement & error calculation is deduced.At the end, the implementation method and calculationformula based on STM32 MCU are given.Experimentresult shows that for the low SNR sinusoidal signal, the method introduced can effectively suppress noise, and increases the accuracy of frequency measurement.
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2015, Vol. 36 
