Film bulk acoustic resonator (FBAR)-based wireless micro quality sensor network node

Abstract

The invention discloses a film bulk acoustic resonator (FBAR)-based wireless micro quality sensor network node, which comprises an FBAR sensor oscillating circuit to be measured, a reference FBAR sensor oscillating circuit, a coarse channel radio frequency tracking circuit, a fine channel intermediate frequency tracking circuit, a programmable processor circuit, a radio frequency transceiving circuit and an antenna. A double-channel differential measuring method and a double-channel frequency tracking control principle are combined, and the closed loop control of a variable local oscillator is realized by the programmable processor circuit, so that high-accuracy and wide-range micro quality real-time measurement is realized, application flexibility is increased, an application range is expanded, and the measuring error of the circuit in severe environment application is greatly reduced.

Description

technical field [0001] The invention relates to a mass sensor in the field of wireless sensor networks, in particular to a wireless micro-mass sensor network node of a film bulk acoustic wave resonator. Background technique [0002] At present, the measurement circuit of the quality sensor adopts the method of two-way differential measurement, that is, one way for the FBAR sensor to be tested and one way for the reference FBAR sensor. [0003] The FBAR sensor to be tested changes the frequency of the output signal of the oscillator circuit of the FBAR sensor to be tested as the perceived quality changes, so as to determine the variation of the quality by measuring the signal frequency. However, due to the influence of temperature, pressure, humidity and some environmental factors and uncertain interference in the measurement process, these factors will also cause changes in the output signal frequency of the FBAR sensor oscillation circuit to be tested. Therefore, another r...

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Problems solved by technology

Therefore, the mutual interference of the three-mixing method structure is large, and because there is no basis for dynamic adjustment of the local oscillation frequency, its measurement range is limited, and it can only be measured for individual types and bandwidths of sensor oscillation circuits, so it is not universal.

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