Miniaturized triple band-notched quasi-self complementary fractal antenna with improved characteristics for UWB applications

Abstract

This paper is a continuation and extension of a previous work [1]. In this paper, an enhanced UWB microstrip-fed quasi self-complementary fractal (QSCF) antenna with triple band notches is presented. These band notches are allocated at 3.5, 5.5 and 7.8 GHz. The proposed design supports coexistence with narrow band applications IEEE 802.16 WiMAX, IEEE 802.11 WLAN and X-band of satellite communications, respectively. Both slot and parasitic loading techniques are utilized to achieve this goal. A guided half wavelength U-shape slot is etched in the ground for creating band rejection at the WiMAX frequency band. To attain the WLAN band rejection, another half wavelength U-shape slot is inserted to the feed line. A split ring resonator (SRR) is embedded to the left and right of the feed line for avoiding interference with X-band. The prospective antenna is designed using low cost FR4 substrate of miniaturized size 32 × 16.5 × 1.5 mm3 which empowers it to be embedded in assorted portable devices. Nearly omnidirectional radiation patterns and stable gain are accomplished over the operating bandwidth from 2 to 11 GHz. For further clarification of the operating principle, an equivalent circuit model is considered showing good agreement with CSTMWS, HFSS and experimental results. Furthermore, a time domain analysis is investigated presenting satisfactory distortion performance between excited and received pulse validating it for diversified UWB applications.