CPW FED CONFORMAL FOLDED DIPOLE WITH PATTERN DIVERSITY FOR 5G MOBILE TERMINALS

A coplanar waveguide (CPW) fed folded dipole with a 20% impedance bandwidth and 4– 6 dBi endfire gain with stable patterns is proposed. Since the proposed element is electrically large (2.1λ × 2λ) conformal topology of this endfire radiator is designed and characterized. The input impedance is not altered significantly compared to the planar element. The radiation in the H plane indicates an increase in specific absorption rate when integrated with a typical mobile terminal. In order to mitigate this effect, a compact (0.8λ×0.8λ) wideband reflector with periodic sinusoidal slots is proposed and mounted with the conformal element at an offset of 0.2λ from the radiator. The proposed antenna has an operating bandwidth from 24 to 30 GHz (20%) with an endfire gain of 6–7 dBi across the band. The front to back ratio is more than 12 dB across the band. Pattern diversity of the conformal antenna is also investigated. Simulated and measurement results are presented in detail.