Wireless surface acoustic wave temperature measurement system reader-writer

Abstract

The invention discloses a wireless surface acoustic wave temperature measurement system reader-writer, which consists of a signal generating unit 101, an amplifier unit 102, a band-pass filter 103, a radio frequency switch 104, a crystal oscillator 105, a local oscillator 106, a band-pass filter 107, a low noise amplifier 108, a filter 109, an intermediate frequency amplifier 110, an analog-digital conversion module 111 and a digital signal processing module 112. The reader-writer has a double phase-locked loop structure, ensures that the expected frequency can be achieved during transmission and receiving, and provides guarantee for accurately measuring temperature.

Description

technical field [0001] The invention belongs to the cross application of wireless radio frequency technology and surface acoustic wave technology, in particular to a wireless surface acoustic wave temperature measuring circuit and a surface acoustic wave radio frequency identification reader-writer based on DSP technology. Background technique [0002] Surface acoustic wave (SAW) is a mechanical wave propagating on the surface of piezoelectric crystal, its sound speed is only one hundred thousandth of the electromagnetic wave speed, and the propagation attenuation is very small. Through the interdigital interchanger, the electrical signal is converted into an acoustic signal, and it is limited to spread on the surface of the substrate. It is used in the measurement of pressure, temperature and other parameters with high accuracy, such as a publication with the publication number CN202305058U A resonant SAW temperature sensor automatic test system, this test system is huge an...

AI Technical Summary

Problems solved by technology

Through the interdigital interchanger, the electrical signal is converted into an acoustic signal, and it is limited to spread on the surface of the substrate. It is used in the measurement of parameters such as pressure and temperature with high accuracy. For example, a publication with the publication number CN202305058U A resonant SAW temperature sensor automatic test system, this test system is huge and complex, and cannot test multiple sensors at the same time. Temperature reader, there is still no relevant technical disclosure of wireless surface acoustic wave temperature measurement reader at present; Another example is a kind of improved UHF RFID reader whose publication number is CN102622571A, although this reader has a far operating distance , but its encoding method is only used to identify information, and cannot achieve the function of measuring temperature

Images