On-Chip 60 GHz Coplanar Folded Slot Antenna with Air Cavity and Reflector

A 60 GHz coplanar folded slot antenna (CFSA) using a silicon-on-insulator substrate, an air cavity, and a back reflector is proposed. The proposed CFSA has a center frequency operating at 60 GHz with a −10 dB impedance bandwidth of 3.3% (58.9-60.9 GHz). The presence of air cavities and reflectors serves to improve efficiency and realized gain. The cross-sectional area of the air cavity occupies only 16% of that of the antenna unit cell. At 60 GHz, the peak gain of the proposed CFSA antenna is calculated to be 5.8 dBi with a directivity of 6.0 dBi. The efficiency of the proposed antenna is simulated to be 95%.