Gas particle concentration measurement method and device on basis of broadband linear frequency modulation ultrasound

Abstract

The invention discloses a gas particle concentration measurement method and a gas particle concentration measurement device on basis of broadband linear frequency modulation ultrasound. The measurement method includes the following steps: constructing a measurement signal by using a linear frequency modulation (LFM) signal, performing digital-to-analogue conversion to the measurement signal and transmitting the converted measurement signal from a transmitting ultrasonic transducer array; detecting an ultrasonic signal by a receiving ultrasonic transducer array, so as to obtain a received signal; performing analog-to-digital conversion to the received signal, and further performing spectrum estimation to the received signal, so as to obtain an attenuation spectrum of the received signal; and moreover, analyzing the obtained attenuation spectrum, determining the linearity of corresponding particles on basis of the frequency, and determining the concentration of corresponding linear particles as per the frequency spectrum amplitude on basis of a mathematical model or an empirical formula. The device for realizing the method includes an operating module, a processing module, a transmitting/receiving module, an outputting module and a measurement cavity. The method and the device, disclosed by the invention, have the advantages of wide application range, high measurement accuracy, simple device, low cost, convenience in use and the like.

Description

[0001] technical field [0002] The invention relates to the technical field of gas particle concentration measurement, in particular to a gas particle concentration measurement method and device based on broadband chirp ultrasound. Background technique [0003] In recent years, air pollution has become more and more serious, and the toxic and harmful substances discharged in human production and life have seriously affected air quality. At the same time, human awareness of environmental protection has improved, so people pay more and more attention to the monitoring of air quality, which also puts forward the demand for particle concentration measurement in gas. In addition, the measurement of gas particle concentration has a wide range of applications in fields such as climate change research and volcano detection. At present, the commonly used particle concentration measurement methods include Ringelmann blackness method, sampling method, capacitance method, charge metho...

AI Technical Summary

Problems solved by technology

However, although ultrasound has a wide frequency range, most of the current methods for measuring particle concentration using ultrasound use single-frequency signals or narrow pulse signals (CN201096703). Although narrow pulse signals have broadband characteristics, they are not easy to generate, and It is not a broadband signal with equal frequency spectrum; in addition, even if there is a broadband signal, most of the current me

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