Microstrip grid array antenna for simultaneous transmission and reception at 24 GHz

This paper presents a dual-port microstrip grid array antenna and a multi-port microstrip grid array antenna on Rogers 5880 substrate for simultaneous transmission and reception at 24 GHz. High isolation between transmitting and receiving ports is achieved by using defected ground plane to weaken the coupling current between the ports. The dual-port microstrip grid array antenna has achieved a high isolation of 31.46 dB at 24.15 GHz, a 10-dB impedance bandwidth of 1.16 GHz, and a maximal realized gain of 18.66 dBi. The multi-port microstrip grid array antenna has achieved a high isolation of 32.80 dB at 24.15 GHz, a 10-dB impedance bandwidth of 0.4 GHz, and a maximal realized gain of 23.20 dBi. The two proposed antennas are suitable candidates for radar and sensor applications.