As the same device may be used for various types of applications, antennas must have the capacity to perform multiple functions. Reconfiguring the polarization, operational frequency, and radiation pattern can create an outcome of multi-functionality. A hybrid, frequency- and pattern-reconfigurable antenna with two V-shaped extrudes in a patch is proposed. To increase the bandwidth of the proposed antenna, the defected ground structure (DGS) phenomenon is presented, which is significant in the bandwidth of 3200 MHz from 2.7 GHz to 5.9 GHz, providing a gain of 3.5 dB. For this design, an FR-4 material was chosen as the substrate, and CST software was used for simulation. Using two p-i-n diodes, the projected antenna illustrates switching for multi-frequency bands such as 1.5, 2.6, 3.2, 5.1, and 8.1 GHz, with a constant radiation pattern and a main lobe direction of 155 degrees. It has C-band, WLAN, cognitive radio (CR), and Bluetooth applications. The proposed antenna displays radiation pattern switching at 3.5 GHz, showing variation between 7°, 158°, 173°, and 175°, and at 4 GHz, it demonstrates switching between 11°, 15°, 165°, and 344°, which defines the hybrid reconfiguration.

A microstrip antenna with a pixel ground structure for single and multiband frequency reconfigurable applications is presented. The partial ground structure of the primary antenna is converted into pixel shapes which produce single and multiband frequency reconfigurable characteristics by the means of RF switches. The designed antenna operations are switchable over multiband, single frequency band and UWB spectrum with the distinct configuration of RF switches. Three cases of RF switch configurations have been demonstrated with their simulated and measured results to verify the reconfigurable characteristics.

A compact triple band notched ultra-wideband (UWB) monopole antenna is presented in this paper. Split Ring Resonator (SRR) structure is exploited in various forms like Complementary Split Ring Resonator (CSRR), Split Ring Resonator Pair (SRRP) and CSRR on Electromagnetic Band Gap (EBG) structure to produce triple band notched characteristics in UWB spectrum. The proposed antenna produces triple band notched functions with integration of all three types of SRR on primary antenna. The parametric analysis of each form of SRR is presented along with their current distribution effects on triple band notched antenna. The proposed antenna prototype is fabricated and measured results are also compared with simulated one to understand the discrepancies. The measured and simulated results are presented to investigate the band notching characteristics of suggested antenna in terms of VSWR and radiation characteristics.

A CPW-fed ultra-wideband (UWB) monopole antenna design which exhibits triple band stop functions is demonstrated. The proposed antenna comprises a Split Ring Resonator (SRR) and inverted U slots on a metallic patch to exhibit triple band-notch functions for WiMAX (3.3-3.6 GHz), Cband (3.8-4.2 GHz) and WLAN (5.1-5.8 GHz) bands. The slot width optimization is examined to tune the band-notch resonance frequency, and their effects are exhibited by surface current distributions. The antenna has compact size of 26 * 30 mm 2 , and it functions over 3 to 11 GHz with VSWR < 2 except notched bands. The SRR loaded dual band-notched antenna and amended inverted U slot integrated antenna both are fabricated and their VSWR, radiation characteristics measured. The antenna demonstrates excellent agreement between measured and calculated results.