Metasurface-Based Microwave Power Detector for Polarization Angle Detection

The detection of electromagnetic power in space is essential for the safe operation of electronic equipment systems. However, as the electromagnetic wave application scenarios become increasingly extensive and complex, it takes a serious challenge to effectively detect the power distribution of fixed-frequency electromagnetic waves over a large area at the same time. This article proposes a metasurface microwave power detector based on a metal resonant disk and load resistors. The detector unit cells can form array of any shape and size, enabling the detection of electromagnetic wave power at arbitrary spatial sizes. The detector unit cell consists of a metal resonant disk, a dielectric layer, a metal backplane, and load resistors. The metal resonant disk converts the received microwave to resonant current by resonance; then, the resonant current flows through the load resistors and is converted as Joule heat, and finally, the microwave power density can be detected by analyzing the heat signal. Simulation results demonstrate that the detector exhibits high absorption efficiency, wide detection angle, and polarization insensitivity. Furthermore, the detector can detect the polarization state of the microwave without any attachments. To verify the proposed method, a $10\times10$ array model is fabricated and measured, and the measured results are found to be consistent with the simulation results. Overall, besides the excellent detection performance and flexibility, the proposed detector also has the advantages of simple structure and low production cost, providing a new solution for large-area microwave power detection.