A Novel Sensor Based on Microstrip Patch Antenna for Detecting Different Gases in Circular Pipe

Abstract

Many industries need a robust sensor to detect and collect information. This paper proposes a sensor based on microstrip patch antennas which are fed by circular waveguide. It can not only realize the function of the antenna but also detect the information about gas as a sensor. When different gases pass through the circular pipe, due to the change of dielectric permittivity, the impedance characteristics of antenna change, which can cause the changes in resonant frequency, return loss, etc. Besides this sensor has advantages of real-time automatic detection, which can reduce the cost of time and manpower. When the inside of the pipe is vacuum, the reflection coefficient of the antenna is less than -20 dB at 24.4 GHz.