Free space and user proximity analysis of octaband monopole MIMO/diversity antenna for modern handset applications

Abstract

In this article, a comprehensive study of the compact octaband monopole MIMO/diversity antenna is carried out in the free space and user proximity. The radiating structure of the proposed antenna consists of a driven element which is directly fed with microstrip line and a parasitic element. However, the designed antenna provides of 730-885 MHz at lower frequency side and 1670-2740 MHz at higher frequency side. Further, to reduce the mutual coupling between two antenna elements, a folded T-shaped structure is designed of electrical length λ/4 at 0.8 GHz and attached to the ground plane. This structure helps in isolation improvement up to the level of −12 dB from −6 dB. The folded structure of T-shaped provides compactness to the proposed antenna. Thereafter, three kinds of user proximity named as Talk mode, Data mode, and Read mode along with mobile phone are studied. Moreover, the specific absorption rate (SAR) is calculated and found well below the standard limit of FCC and European standard. Finally, the proposed antenna is fabricated and tested. The measured results are in close agreement with simulated results.