A compact reconfigurable microstrip slot antenna with switchable single and dual band notch functions for ultra‐wideband (UWB) applications is presented in this study. In the proposed structure, an additional resonance is excited by etching two symmetrical notches on the feed‐line and thereby a UWB characteristic is obtained. Then, by cutting two slots on the radiating patch and embedding two positive‐intrinsic‐negative (PIN) diodes along these slots, switchable single and dual band notch performances are added to the antenna performance. By changing the bias states of the PIN diodes, the antenna is capable of exhibiting four different performances of UWB spectrum coverage, UWB coverage with single rejection of the wireless local area network (WLAN) band, UWB coverage with single rejection of the WiMAX and C‐band spectrum, and UWB coverage with dual band notch function at the WLAN, the WiMAX and the C‐band frequencies. Good agreement between the simulated and the measured results is achieved at different performances of the antenna. The designed antenna has a small size of 20 × 20 mm2 and the measured results reveal that the fabricated antenna has good radiation behaviour in the UWB frequency spectrum with switchable band notch functions at 3.15–3.85 and 5.43–6.1 GHz which can eliminate the UWB frequency band interference with the WiMAX, the C‐band and the WLAN systems.

No abstract

No abstract

A novel design of ultra‐wideband (UWB) reconfigurable pulse generator (PG) active‐integrated antenna (AIA) is introduced and discussed in this study. The reconfigurable structure of the proposed PG AIA provides pulse‐shape modulation which is desirable for most UWB communication systems. The presented design utilises only a single step‐recovery diode and just a single positive‐intrinsic‐negative diode in order to generate sub‐nanosecond switchable monocycle/doublet pulse shapes. Since in UWB communication systems the design of source pulses and transmitting/receiving antennas should be optimal for the performance of overall systems both frequency domain and time domain characteristics of the designed PG AIA are carefully investigated under realistic conditions. The pulse distortion is insignificant in the operating band and is verified by the measured PG AIA performance with low ringing level, high signal fidelity, and virtually steady group delay. The presented design is a good candidate for UWB transmission because of its simplicity, low cost, and good performance.

No abstract