An AMC-Based Liquid Sensor Optimized by Particle-Ant Colony Optimization Algorithms

This paper proposes a liquid sensor based on artificial magnetic conductor. The artificial magnetic conductor structure is optimized numerically using particle-ant colony optimization algorithm to increase the freedom of structural optimization exploration while reducing the time consumption. In the optimization process, the resonant frequency is kept at 2.45 GHz to ensure that the operating frequency is within the industrial scientific medical (ISM) band. The optimized artificial magnetic conductor is combined with a broadband antenna to build a liquid sensor. The designed sensor is fabricated and tested by loading butan-1-ol, propan-2-ol, ethanol, methanol, and water. The liquid samples can be injected directly into the channel without the need for additional expensive microfluidic chip such as polydimethylsiloxane, thereby greatly reducing the fabrication cost. A maximum sensitivity of 3.48% and a wide application range up to 78 are achieved, verifying the potential of the proposed sensor for low cost and real time monitoring of liquid samples in practical applications.