This paper proposes the step-by-step design procedure for obtaining independent dual band-notch performance, which provides a valuable method for designing tunable dual band-notched UWB antenna. The proposed antenna consists of the semicircle ring-like radiating patch with an elliptical-shaped slot and double split ring resonators on the top surface of the substrate and defected ground structure (DGS) on the bottom surface of the substrate. The operating frequencies ranged from 1.3 to 11.6 GHz (S11 < − 10 dB). By loading varactor diodes at the gap of the resonators structure and changing the varactor diode’s reverse bias voltage(0–30 V), a wider band-notched tuning range from 2.47–4.19 to 4.32–5.96 GHz can be achieved, which covers the whole WiMAX band and WLAN band. The experimental results agree well with the simulated results. The notched gain at notched frequency points is about − 5.3 dBi and − 5 dBi, demonstrating that the narrow-band interference signal could be efficiently suppressed. The security of UWB communication systems can be further enhanced. Meanwhile, the selection of varactor diode and DC bias circuit are fully considered. Hence, the accuracy of the experiment results and antenna operating performance have been improved. Furthermore, the proposed antenna only has an electrical size of 0.26λ*0.19λ at 1.3 GHz. Compared to the related reported antennas, the proposed antenna has achieved a simpler structure, low profile, compact size, tunable dual band-notched characteristics, extensive independent tunable range, and good band-notched performance simultaneously, to the best of our knowledge. The proposed antenna is believed to have a valuable prospect in UWB communication, Wireless Body Area Network, Industry Science Medicine, mobile communication applications, etc.

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In this paper, a miniaturized ultra-wideband( UWB) microstrip antenna with independent tunable double band-notched characteristics is presented, which consists of the semicircle ring-like radiating patch with an elliptical-shaped slot and double split ring resonators(SRRs) on the top surface of the substrate and defected ground structure(DGS) on the bottom surface of substrate. The operating frequencies have range from 1.3GHz to 11.6GHz(S11<-10dB). The double band-notched characteristics have been achieved by etching elliptical-shaped slot at the radiating patch and placing double C-shaped SRRs at the both side of the microstrip feed line. By loading varactor diodes at the gap of the elliptical-shaped slot and the double C-shaped SRRs and changing the reverse-bias control voltage of the varactor diodes, the notch frequency can be electronically tuned efficiently. The experimental results, which are agree well with the simulated results, demonstrate that the proposed antenna have created the notched frequency band shift from 2.47GHz to 4.19GHz(1.72GHz) and 4.32 GHz to 5.96GHz(1.64GHz) when the reverse bias voltage vary from 0V to -30V corresponding to the junction capacitance of varactor diode has decreased from 2.67pF to 0.63pF, which imply that the proposed antenna with band-notched characteristics has the capability to suppress the narrow interference signals which cover the wireless local area network(WLAN) and world interoperability for microwave access(WiMAX) band. Furthermore, the proposed antenna structure only has the electrical size of 0.26λ*0.19λ at 1.3GHz. Compare to the related reported antennas, the proposed antenna has achieved compact size, tunable dual band-notched characteristics and good band-notched performance simultaneously to the best of our knowledge. It is believed that the proposed antenna will have a very valuable prospect in the fields of wireless body area network (WBAN), UWB communication, Internet of Things(IoT), etc.