Optimized broadband and dual-band printed slot antennas for future millimeter wave mobile communication

In this paper, a broadband and a dual-band printed slot antennas for the future millimeter wave mobile network communication are proposed. The antennas are designed for Ka-band frequency of operation. The basic antenna design consists of a circular radiating patch that is placed non-concentrically inside a circular slot etched off the ground plane. Matching between a radiating patch and the 50 Ω microstrip line is manipulated through a proximity-feed technique. The simulated antenna prototype – I and prototype – II are fabricated and successfully measured. The results indicate that the proposed antenna prototype – I yields the broadband impedance bandwidth >20 GHz (from 20 to >40 GHz) define by S11 < −10 dB that covers two important millimeter wave frequency bands (28/38 GHz). To reduce the interference between the different applications operating around these frequency bands, the L-shaped slot is etched off in prototype – II feedline to create a notched band of 30–35 GHz. The measured results show that the designed antenna has dual-band at 28 and 38 GHz with a band notched at 33 GHz. The low profile/cost broadband antenna (prototype – I) and dual-band antenna (prototype – II) has the measured gain upto 5.30 dBi and 5.6 dBi with the estimated radiation efficiency of 93% and 94%, respectively. The simulations are performed using industry-standard software CST MWS and HFSS. The measurements are in a good match with the simulated results.