Investigation of a defected ground structure inspired wideband printed monopole mobile antenna using characteristics mode analysis.

In this research article, a wideband mobile antenna with defected ground structure (DGS) is designed using characteristics mode analysis. It consists of a modified crescent‐shaped monopole antenna (M‐mode), L‐shaped stub (S‐mode), and DGS element (slot modes). Here, the fundamental resonating modes of M‐ and S‐mode are induced to operate in the integration mode (I‐mode) to obtain good impedance bandwidth (IBW). The DGS is implemented in ground plane to get slot modes (1 and 2). By combining slot modes with M‐mode and S‐mode, it exhibits broadened IBW (i.e., C‐mode), is suitable for the coverage of mobile bands (sub‐6 GHz frequency bands). For the clarity, modal investigation is performed at each critical stages of antenna designing process and the modal metrics like modal significance, characteristics angle (βn), Eigen values (λn), modal currents, and modal patterns are extracted by using Computer Simulation Technology (CST) Studio Suite. The proposed monopole antenna operates in multiband for wireless applications, that is, 880–960 MHz, 2.3–2.4 GHz, 2.4–2.483 GHz, 3.3–4.2 MHz, 3.3–3.8 GHz, 5.15–5.85 GHz, and WLAN (IEEE 802.11 b/g/n) respectively with measured gain of 3–5.5 dBi. A prototype of proposed antenna is fabricated and measured, which shows good agreements with simulation. To validate, averaged specific absorption rate (SAR) is investigated with 3D voxel phantom human head and hand model. The observed SAR 1 g lies between 0.0014 and 0.0462 W/kg in the operating bands, which are under the limits prescribed by the Federal Communications Commission (FCC). From the above outcomes, it can be potentially used in the mobile handsets and also, can be extended to hybrid wireless cellular communication networks & potential applications like RF energy harvesting. [ABSTRACT FROM AUTHOR]