谐振式压力传感器频率测量算法研究

摘要

利用DSP高速、内存大的特点，对谐振式压力传感器输出信号进行等精度测量，以提高系统的整体测量精度。针对无线信号传输中 FFT 算法频率估计误差大的问题，提出一种基于FFT 变换的改进 Rife 算法。改进 Rife 算法的思想是：若被估计信号频率接近于 FFT 量化频率，则对信号进行频移以使信号频率位于两相邻量化频率中心，再用改进的 Rife 算法公式估计频率，频移方向由 Quinn 法确定。通过 MATLAB 仿真实验证明了改进算法的有效性。%As per the advantages of high speed and large memory of DSP,the resonant pressure sensor output signal is measured with equal precision to improve the overall accuracy of the system.For the accuracy problem caused by the estimation wireless signal transmission of FFT algorithm frequency, then,an improved Rife algorithm based on FFT transform is proposed.The concept of Rife algorithm is that,if the estimate signal frequency close to the FFT frequency,the signal frequency shift is conducted to make the signal frequency in the center of two adjacent sampling frequency,then the improved Rife algorithm is used to estimate frequency as the frequency shift direction determined by Quinn method.The MATLAB simulation proves the validity of the improved algorithm.