A surface acoustic wave sensor chip structure and sensor

Abstract

The invention discloses a chip structure of an surface acoustic wave sensor. The structure comprises a piezoelectric substrate (21) and an interdigital transducer (20), wherein the interdigital transducer (20) comprises a bus bar (22) and an electrode part (23); the electrode part (23) adopts a sharp corner structure; the piezoelectric substrate (21) is used for accumulating electric energy; and the interdigital transducer (20) is used for converting the electric energy into mechanical energy, modulating an acoustic wave signal on a propagation path, converting the mechanical energy into the electric energy through an inverse piezoelectric effect and providing the energy for the surface acoustic wave sensor. According to the structure, the reading-writing range of the SAW sensor can be greatly expanded, so that longer-distance receiving is realized and the demands of a sensor market on the reading-writing range are met.

Description

technical field [0001] The invention relates to the field of signal and information processing, in particular to a surface acoustic wave sensor device. Background technique [0002] Surface Acoustic Wave (SAW, Surface Acoustic Wave) sensors are widely used in the monitoring of many physical quantities such as pressure, temperature, and strain due to their good performance, small size, and low cost. [0003] A general wireless passive SAW sensor is composed of a sensor chip and a reader. The sensor chip receives the radio frequency signal emitted by the reader through the antenna. Based on the piezoelectric effect, the interdigital transducer of the sensor chip converts electrical energy into mechanical energy, modulates the acoustic signal on the propagation path, and converts mechanical energy into electrical energy through the inverse piezoelectric effect. , to provide energy for the sensor. However, since the energy of the SAW sensor comes from the reader, and the radio...

AI Technical Summary

Problems solved by technology

However, since the energy of the SAW sensor comes from the reader, and the radio frequency signal is severely attenuated in the atmosphere, the received signal is very weak, and the energy generated by the piezoelectric effect is very weak, which seriously restricts the reading and writing distance of the SAW sensor.

At present, the longest distance that SAW wireless sensors can achieve is 6 meters, which cannot fully meet the needs of the sensor market.

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