A compact MIMO UWB antenna with band notched characteristicsat WLAN frequency band

Abstract

This work presents a compact UWB MIMO antenna with band notch characteristics for WLAN application is designed and investigated. The proposed MIMO antenna consists of two unit cell antennas, being comprised of a Microstrip feed line and a partial ground plane, and these radiators are placed parallel to each other. A single antenna comprises an inverted Christmas tree shaped patch fed by a 50 OMicrostrip line and partial ground plane is designed for achieving UWB application. The operating frequency of the proposed single antenna is 3.5–14.5 GHz with a return loss of less than -10 dB. Subsequently, a circular split ring shaped slot is implemented in the radiating element to optimize the antenna for WLAN band rejection at 5.6-6.2GHz. Furthermore, a 2 × 1 MIMO antenna is designed by utilizing the polarization diversity technique. The two radiating elements are placed parallel and decoupling structure is placed between them to improve the isolation performance. Finally, the compact UWB MIMO antenna prototype is designed on the FR4 substrate with the overall dimensions of 20 × 39 × 1.63 mm3.The proposed UWB MIMO antenna design provides an impedance bandwidth (S11 less then -10 dB) of 130% (3.3–16 GHz) with band notch centered at 5.8GHz. The isolation of the proposed MIMO antenna is higher than -17?dB,. Results show that the proposed MIMO antenna is a good candidate for handheld devices for wireless personal-area networks application.