Wide-response-band particle vibration velocity sensor

Abstract

The invention relates to a wide-response-band particle vibration velocity sensor, which comprises a sensitive element, and is characterized in that the sensitive element (2) comprises a substrate (21)on which a bridge opening (211) is formed, and a plurality of sensitive wires (20) which are arranged on the bridge opening (211) in parallel; and each sensitive wire (20) sequentially comprises a sensitive material layer (206) and a supporting layer (205) from top to bottom, and the sensitive material layer (206) is of a hollow structure. By adopting the sensitive wires with the hollow structures, the equivalent density of the sensitive wires is reduced, so that the heat mass of the sensitive wires is reduced, the heat exchange rate of the structure is improved, the upper limit of the response frequency of the sensor is effectively improved, the response frequency band of the sensor is expanded, and the mass point vibration velocity of a broadband sound signal can be detected without distortion.

Description

technical field [0001] The invention relates to the field of sensors, in particular to a particle vibration velocity sensor with a wide response frequency band. Background technique [0002] The acoustic signal contains two parameter values, the scalar sound pressure signal and the vector particle velocity signal, which respectively reflect different characteristics of the sound field. Among them, the sound field vector particle velocity signal carries the information of the direction of sound wave propagation, which can be used in many aspects such as sound source location and tracking, sound field imaging, etc., and has broad application prospects in various fields such as aeroacoustics and hydroacoustics. For scalar sound pressure signals, it can be measured by various sensors such as electret condenser microphones and piezoelectric transducers. For the acoustic vector signal, the traditional measurement method is generally based on the principle of sound pressure gradie...

AI Technical Summary

Problems solved by technology

[0006] However, due to the limited thermal mass of the sensitive layer material of the traditional thermal temperature difference particle vibration velocity sensor based on the above structure, it is difficult for the heat exchange rate to keep up with the change rate of the acoustic wave amplitude when responding to high-frequency acoustic signals, thus failing to achieve a wider response frequency band

This will lead to a series of problems such as distortion of the sensor when detecting broadband sound signals, large noise in the frequency band, etc.

This defect directly affects the detection of broadband sound signals by the particle velocity sensor, which limits the application scenarios and scope of application of the particle velocity sensor

Although companies such as Microflown have expanded the response frequency band of thermal temperature difference particle vibration velocity sensors to a certain extent through hardware circuits and other methods, they have also introduced greater noise.

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