In recent year, various filtenna circuits have been developed satisfying the objectives and prerequisites of wireless communication. Some of these developed designs are new or some are the improved version of previous works whereas the others are the combination of conventional methods. This article presents the review of filtenna circuits starting from the beginning to the improvements until date. This article starts with brief overview of various filters with their design strategies and ends in its implementation in filtenna designs followed by discussion on several filtenna designs in term of size and overall performances. Among various designs, bandpass, and bandstop filters are extensively used in filtenna realization as it provides a better selectivity in desired band. Various planar filtenna circuits, based on either defected ground structure (DGS) or resonator or SIW filters are reviewed and presented. Besides, planar filtennas, these filters are also integrated to the aperture of horn antennas for the realization of horn filtennas, applicable for high frequency operations. It is observed that SIW based filtennas exhibited narrow impedance bandwidth. This feature can be improved by doubling substrate layer as well as the number of metallic ways. Whereas, resonator based filtennas use resonator based filters along with DGSs to enhance impedance bandwidth as well as minimize mutual coupling and cross‐polar radiation. Apart from single element filtenna, filtenna arrays, and reconfigurable filtennas (including planar and horn reconfigurable filtennas) are presented. This review article may be helpful for beginners working on filtenna circuits and also such a review process is not available in the open literature to the best of author's knowledge.

A microstrip patch filtenna inspired by defected ground structure (DGS) is presented in this article. It uses modified split ring resonator and capacitance loaded strip as a radiating element. The presented structure is incorporated with a pair of double U-shaped DGS (DU-DGS) to obtain filtering characteristics. The width of DU-DGS plays a vital role in selecting attenuation poles of the filter as well as for the filtenna circuit. The separation distance between the DU-DGS also affects the resonant frequency of the structure. Both radiation and filtration can be performed through a single structure, otherwise known as filtenna. The physical size of the proposed filtenna in terms of guided wavelength is 2.465λ g × 1.160λ g × 0.116λ g at 10.8 GHz, and is comparatively less to others reported, so is considered as a superior feature. The presented filtenna possesses impedance bandwidth of 700 and 1800 MHz at 10.8 and 16.6 GHz, which covers standards of X-and Ku-band, respectively. So, this can be referred to as dual band filtenna. The radiation pattern shows omnidirectionality in both E and H planes at resonance. K E Y W O R D Sdefected ground structure, dual band, filtenna, omnidirectional, split ring resonator

A new multiband coplanar waveguide fed zeroth‐order resonant (ZOR) antenna structure with improved bandwidth is proposed. This antenna achieves multiband functionality in five different frequency bands in the range of 2.5–5 GHz. The ZOR frequency is observed to be at 3.97 GHz. The bandwidth improvement, gain, and antenna efficiency at this frequency is found to be 3.28%, 1.9769 dB, and 73.42%, respectively. The proposed antenna is measured at antenna measurement facility, and results were compared with the simulated results. A good agreement between the measured and the simulated results validates the proposed design. The designed antenna proposed in this article holds potential applications in modern wireless communication systems which require multiband antennas with good radiation characteristics. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE 22:569–574, 2012.

ABSTRACT:The proposed paper addresses the setback of congestion in wireless sensor networks by introducing a mobile sink to reduce congestion. Moreover, in the considered method data has to voyage a restricted number of hops to arrive at the mobile sink which helps to improve the energy consumption of the sensor nodes. Parameters like packet delay, packet loss and throughput are measured for estimation. Since, congestion sternly affects the performance of wireless sensor networks, it has to be minimized in order to boost the life span of a sensor network. The mobile sink approach used in the planned scheme is very much effective in minimizing the congestion in the sensor network. In this model, the sink is not stationary, but it is mobile. With the use of simulation, the utility of the considered scheme in terms of congestion minimization in wireless sensor network is shown.

No abstract