Apparatus and method for measuring resonant frequency of acoustic surface wave device by adopting wide-band excitation

Abstract

The invention relates to an apparatus for measuring resonant frequency of an acoustic surface wave device by adopting wide-band excitation. According to the measuring apparatus, broadband modulating signals are generated through an FPGA, and radio-frequency signals are generated by the broadband modulating signals and local oscillation signals of a local oscillator through frequency mixing of a frequency mixer; the radio-frequency signals are emitted out through an antenna after being amplified through a power amplifier, and the acoustic surface wave device absorbs the signals with frequency close to the resonant frequency of the acoustic surface wave device, then reflects the signals to the antenna and transmits the signals to a signal receiving unit; the signal receiving unit outputs intermediate frequency signals and RSSI signals through a receiver, an A / D processor performs sampling on the intermediate frequency signals and the RSSI signals, a signal processing unit compares the RSSI signals with a signal intensity designated value, and if the RSSI signals are larger than the designated value, the signal processing unit performs FFT conversion processing on the intermediate frequency signals to calculate the resonant frequency of the acoustic surface wave device. The measuring apparatus can emit the radio-frequency signals with multiple frequency point energy at the same time, so that resonant frequency measurement of the acoustic surface wave device is finished within a transmitting-receiving period, and the measuring speed is high.

Description

technical field [0001] The invention relates to a non-contact remote measuring device, in particular to a non-contact remote measuring device for identifying the frequency of a surface acoustic wave device. Background technique [0002] Remote non-contact measurement technology is widely used in military, environmental protection, medical, industrial control and other communication fields. Surface acoustic wave devices have strong anti-interference ability, high sensitivity, good linearity and repeatability within the detection range, and are very suitable for remote non-contact measurement. Contact measurement technology. However, because in the prior art, the change of the resonant frequency of the SAW device caused by the change of the physical quantity, chemical quantity or biomass in the surrounding environment is only observed as a phenomenon, there is no specific resonant frequency Measurement, so surface acoustic wave devices are not well used in remote non-contact ...

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Problems solved by technology

However, because in the prior art, the change of the resonant frequency of the SAW device caused by the change of the physical quantity, chemical quantity or biomass in the surrounding environment is only observed as a phenomenon, there is no specific resonant frequency Measurement, so surface acoustic wave devices are not well used in remote non-contact measurement technology

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