High-sensitivity Microwave Sensors Based On Metamaterials

High-sensitivity microwave integrated sensors are important for the development of the economy and society.Planar integrated microwave devices with higher sensitivity and smaller size can be realized by metamaterials.This thesis focuses on the research of high-sensitivity planar integrated microfluidic sensors based on metamaterials at microwave frequencies.The research contents and results are summarized as follows:1.A passive sensor combining a quarter-mode substrate integrated waveguide(SIW)and complement split-ring resonator(CSRR)was proposed.The value of the quality factor(Q)of the sensor is improved and its electrical size is reduced by ～1/3,realizing a compact and high-sensitivity microfluidic microwave sensor.2.An active amplifying resonator based on a grooved metal ring is designed.By loading a low noise amplifier(LNA)chip,the internal Ohmic loss of the device can be greatly compensated and its Q value has been significantly increased.Amplified spoof localized surface plasmons(LSP)were first demonstrated and the working mechanisms were explored in details.3.An active microwave sensor based on the spoof LSP resonator loading an LNA chip at 45-degree slit has been proposed.By compensating the internal loss and the loss of the under test liquid,its Q value can be increased by nearly 2000 times.Different liquid detection experiments verified the high sensitivity.4.A microfluidic glucose sensor based on the amplifying spoof LSP is designed.By introducing two coupling stubs with the amplifier chip,a glucose solution sensor with ultra-high sensitivity and resolution has been designed,whose resonant modes are unchanged.5.A set of glucose solution concentration detecting system based on the active spoof LSP sensor was designed to realize the integrated system prototype including RF source and detection analysis.