A Compact Two-element MIMO Antenna with High Isolation and Dual Band-Notched Characteristics for UWB Communication Systems

A novel compact two-element MIMO antenna with dual band-notched characteristics for ultra-wideband communication systems is presented and discussed. The proposed antenna consists of two identical and symmetrical radiating elements spaced by 19 mm (0.197 λ₀). The main radiating element is composed of a circular and trapezoidal segment, fed by a tapered microstrip line with a common ground plane. In addition, L-shaped and C-shaped slots are inserted in the main radiating element to reject the WLAN band (5.15–5.8 GHz) and the INSAT C-band (6.3–7.3 GHz), respectively. The proposed antenna with dimensions of 22 mm × 34 mm × 1.6 mm has a measurement operating frequency band from 3.1 to 23 GHz (152.4%). Inverted L-shaped stubs and a wide slot are introduced into the ground plane to achieve high isolation between the two ports. The proposed antenna has good MIMO diversity performances; the minimum measured isolation is 22 dB for the entire operating band, the envelope correlation coefficient (ECC) is less than 0.001, the diversity gain (DG) is near 10 and the channel capacity loss (CCL) is less than 0.29 bits/s/Hz, whereas a maximum total active reflection coefficient of − 35 dB is achieved for the whole operating band.