Investigation And Measurement System Of CSRR Integrated SIW Sensor In High-temperature Environments

Real-time in-situ measurement of multi-parameters(e.g.,temperature,pressure,humidity)in high-temperature environment has a wide range of demands in the fields of aerospace,energy extraction and transportation.At present,wireless and passive sensing technology has the great potential due to its non-contact measurement method.Microwave scattering technology is a promising candidate for monitoring environmental parameters in harsh environments,due to its advantages of long-distance signal transmission,high sensitivity,accuracy and Q factor,little metal background interference.Therefore,this paper proposes a wireless and passive microwave temperature,pressure and multi-parameter sensor based on the complementary split resonance ring integrated substrate integrated waveguide structure(CSRR-SIW).The HFSS simulation software was used to simulate and verify the feasibility of the propose sensors.This paper has designed the temperature correction algorithm for pressure parameters and a modular measurement system.The successful development of such wireless microwave sensors is a new idea in harsh environments for wireless multi-parameter measurements.The main research contents are as follows:(1)The CSRR structural model and equivalent circuit are established,the influence of CSRR structural parameters on its resonance frequency is analyzed,and the wireless transmission principle of the CSRR-SIW microwave sensor is clarified.By analyzing the temperature sensitive mechanism of the CSRR-SIW temperature sensor and the pressure sensitive mechanism of the CSRR-SIW pressure sensor,the thermal-electric coupling model of the CSRR-SIW temperature sensor and the thermal-mechanical-electric coupling model of the CSRR-SIW pressure sensor are established.In addition,parameter analysis and influencing factors of characteristic signals are studied.(2)It is proposed to integrate the CSRR structure on the SIW resonant cavity to realize the design of the high-temperature temperature sensor.The HFSS simulation software is used to simulate the effect of temperature on the resonant frequency of the sensor,and then the sensor is tested using the high-temperature test platform.The temperature sensor can achieve hightemperature test of 1200 ?.Based on the similar working principle,the CSRR structure is integrated on the SIW resonator with a sealed cavity to realize the design of the hightemperature pressure sensor.The COMSOL simulation software is used to analyze the mechanical parameters of the sensor.The HFSS simulation software is used to analyze the effect of pressure on the resonance frequency of the sensor,and verify the feasibility of the CSRRSIW pressure sensor.Based on the HTCC three-dimensional integrated manufacturing technology,the manufacture of the pressure sensor was completed.The pressure sensor can work stably at a high-temperature pressure environment of 800 ? and 300 kPa,and the pressure sensitivity at 800 ? is 206.89 kHz/kPa.In addition,the three pressure sensors loaded with different CSRR structures,which can be designed by changing the parameters of the CSRR,are employed for multiple discrete frequency bands to realize the multi-site and netted pressure testing.(3)A wireless slot-antenna integrated temperature-pressure-humidity(TPH)sensor loaded with CSRR for harsh-environment applications was presented.The sensor is a multi-resonance structure with three separate resonant frequencies,which renders simultaneous measurements of temperature,pressure and humidity by placing sensitive elements in the corresponding CSRR structures.The working principle of the multi-parameter sensor is explained by the equivalent circuit model and the electric field distribution at different resonance frequencies simulated by HFSS.The morphology characterization of GO@PI sensitive film was realized by SEM,and EDS.At the same time,the temperature correction algorithm of the pressure signal was proposed to achieve the accurate acquisition of the pressure signal under the variable temperature environment.Finally,the TPH sensor were tested using a high-temperature temperature-pressure-humidity composite test platform.In order to realize the multi-parameter miniaturized high-temperature sensor design,it is proposed to use a resonance frequency point to achieve simultaneous acquisition of temperature and pressure parameters.The resonance intensity is used to monitor the temperature changes,and the resonance frequency is used to characterize pressure changes.Finally,the sensor is tested using a high-temperature pressure test platform and the feasibility of the method is verified.The temperature sensitivity is 0.0133 dB/°C,and the pressure sensitivity at 800°C is 235 kHz/kPa.(4)In order to realize the miniaturization,portability and integration of the microwave sensor measurement system,the hardware and software modules of the modular measurement system are designed.The phase-locked loop frequency synthesis technology is used to transmit the sweep signal,combined with the power divider and directional coupler,attenuator,phase discriminator,MCU and other circuit components realize the extraction of characteristic signals of microwave sensor from 35 MHz to 2.7 GHz,and the test error is less than 1%.The experimental platform of buried pipeline is built,and the characteristic signals of the sensor buried under the sand are extracted by the modular measuring circuit.