A Miniaturized Millimeter-Wave Radar Sensing Microsystem With High Isolation Full-Duplex Microstrip Patch Antenna

In this letter, a novel miniaturized 24-GHz millimeter-wave (mmW) radio frequency (RF) microsystem with a high isolation full-duplex patch antenna (FDPA) is proposed for short-range radar sensing. By adopting a novel dual-decoupling technique combining defected ground structure (DGS) and a decoupled inductance, an FDPA with high Tx/Rx isolation of >62 dB is achieved. By integrating the RF circuit with the proposed FDPA, the prototype of a custom-designed miniaturized radar microsystem with a whole size of just $10\times10$ mm is designed, fabricated, and measured. The experimental scenes to test the features of the proposed microsystem are also given. Experimental results demonstrate the feasibility and accuracy of short-range radar sensing applications.