A compact UWB monopole patch antenna with reconfigurable Band-notched characteristics for Wi-MAX and WLAN applications

Abstract A compact planar monopole elliptical UWB antenna with a microstrip band-stop filter using a Slot-Type Split-Ring Resonator (ST-SRR) is analyzed and presented in this paper. In order to improve the impedance matching and operating bandwidth of the proposed antenna, a partial defected ground plan is utilized. The ST-SRR structure is inserted into the center of the feed line of the UWB antenna to achieve notch band characteristics to reject interference with the wireless local area network (WLAN) IEEE802.11a/h/j/n (5.15–5.35 GHz, 5.25–5.35 GHz, 5.47–5.725 GHz, 5.725–5.825 GHz) and Wi-Max (IEEE802.16 3.30–3.80 GHz). A pin diode is inserted in the ST-SRR structure in order to achieve reconfigurability in the notch band function. The measured result shows that the proposed antenna operates over 2.7 to 14.9 GHz with a fractional bandwidth of 138.63% for S11 ≤ −10 dB. By controlling the PIN diode at OFF and ON states, the notch bands of the proposed UWB can be switched in the range of 3.43–3.75 GHz and 4.87–6.40 GHz, respectively. Good agreement between the simulated and measured results is achieved. The obtained results show that the proposed antenna is a good candidate for reconfigurable UWB communication applications.