Vortex information retrieval system base on relaxing notch periodogram

This paper describes the relaxing notch periodogram (RNP) method, basing on the characters of vortex signal and research findings of maximum likelihood (ML) estimate. This method possesses high frequency resolution, computational efficiency and noise immunity. Moreover, the results of simulation and experiment prove that RNP method is effective on improving flow meter accuracy, extending measuring range and strengthening anti-interference. While a low power signal processing system of vortex flowmeter is presented which is based on double-cores composed of digital signal processor (DSP) and microcontroller (MSP430). It is verified by the experiment that this system has the feature of high anti-interference, extended measuring range, low power, and real time data processing.