International Journal

In this paper, a rectangular dielectric resonator antenna (DRA) with a parasitic gap-coupled microstrip resonator (MSR) is investigated; analytically, and experimentally. The proposed antenna uses an open-ended half-wavelength MSR patch as a hybrid radiator. Radiating modes are identified for both the radiators. Two separate and fully independent modes are merged together to get an enhanced bandwi

This paper presents the modeling, manufacturing, and testing of a micro-electromechanical system (MEMS)-based LC tank resonator suitable for low phase-noise voltage-controlled oscillators (VCOs). The device is based on a variable MEMS varactor in series with an inductive coplanar waveguide line. Two additional parallel stubs controlled by two ohmic MEMS switches have been introduced in order to in

In this report, a compact antenna system with dual-band-notched characteristics is proposed for ultra-wideband (UWB) multiple-input multiple-output (MIMO) applications. Two antenna elements are placed side by side and fed with matched microstrip lines on a substrate with an area of 35 × 30 mm. Notched characteristics at WiMAX (3.4?3.6 GHz) and WLAN (5.725?5.825 GHz) have been achieved using comple

A coplanar waveguide (CPW)-fed circular-shaped fractal antenna with third iterative orthogonal elliptical slot for ultra-wideband applications is presented. The bandwidth is enhanced by using successive iterations of radiating patch, CPW feedline, and tapered ground plane. An impedance bandwidth of 2.9?20.6 GHz is achieved. The designed antenna has omnidirectional radiation patterns along with ave

Wideband dipole antennas are proposed using the multi-mode resonance concept. By symmetrically introducing one-pair or two-pair of stubs at the nulls of current distribution of the second odd-order mode, two radiation modes are excited in a single, center-fed dipole resonator. Using these stubs, the second odd-order mode gradually moves down to its first counterpart, resulting to achieve a wideban

A simple and compact printed ultra-wideband antenna with dual-band-notched characteristics is presented. The proposed antenna is composed of a rectangular patch and a modified ground plane. The rectangular patch is etched onto a lossy FR4 substrate. A circular ring strip parasitizes the rectangular patch embedded by a U-shaped slot. Two inverted-L slits and a rectangular slit are embedded onto the

This paper describes a new configuration of frequency-selective structure (FSS) structures to reduce mutual coupling between the radiating elements. Also, the antenna performance before and after the implementation of FSS have been investigated. The proposed configuration provides an improvement in mutual coupling by 14 dB (measured value) with a reduced edge-to-edge spacing of 23 mm. The reductio

Patch antennas with a meandering slot and different distributions of grounded metallic vias are presented in this paper. The meandering slot is adopted to stimulate dual-band operation, while the number and position of the grounded metallic vias are suggested to achieve different radiation performances. The characteristics are analyzed in detail where we find that the existence of the vias also im

A coplanar waveguide-fed planar hexagonal monopole ultra-wideband antenna with dual-band rejection characteristics is proposed in this paper. The desired notch frequencies at 3.5 and 5.5 GHz are realized by incorporating mushroom structures. The input impedance and surface current distributions are used for analysis and explanation of the effects of mushroom cells. The prototype and proposed anten

This paper of lettering reveals about a modified Koch snowflake fractal multiband antenna for cognitive radio applications. Multiband antennas can be employed for spectrum sensing in cognitive radio. This new microstrip-modified Koch fractal antenna exhibits multiple actions in four dissimilar resonant frequencies at 3.2, 5.2, 6, and 9.5 GHz correspondingly that covers the frequency bands such as