In-Situ Wireless Pressure Measurement Using Zero-Power Packaged Microwave Sensors

Area of Science:

• Wireless Sensor Technology
• Microwave Engineering
• Electromagnetics

Background:

• Remote pressure monitoring is crucial in various industrial applications.
• Existing methods often require wired connections or active power sources for sensors.
• Development of passive, wireless sensors offers a significant advantage in accessibility and deployment.

Purpose of the Study:

• To report on indoor wireless measurements of pressure using zero-power microwave sensors.
• To detail the design, fabrication, and packaging of these passive pressure sensors.
• To evaluate the performance of 3D radar imagery for interrogating these sensors in reverberant environments.

Main Methods:

• Fabrication and packaging of zero-power microwave pressure sensors operating at 24 GHz.
• Measurement of sensor scattering parameters to determine pressure sensitivity.
• Application of 3D radar imagery for remote sensor interrogation in electromagnetic reverberant environments.

Main Results:

• Achieved a sensor sensitivity of 995 MHz/bar over a pressure range of 0.8 to 2.1 bars.
• Demonstrated a full-scale measurement range of 1.33 GHz for scattering parameter measurements.
• Obtained a dynamic range of 4.9 dB and sensitivity of 4.9 dB/bar (0.7–1.7 bars) using radar detection.
• Successfully interrogated passive pressure sensors wirelessly in a highly reflective environment.

Conclusions:

• The developed zero-power microwave sensors enable remote pressure measurement up to 2.1 bars.
• The 3D radar imagery technique is effective for interrogating passive sensors in complex electromagnetic settings.
• This work presents a novel approach for wireless, passive pressure sensing in challenging environments.