Coupled-mode theory is applied to obtain an analytic form of scattering parameters for a class of transmission line metamaterials with antisymmetric split-rings. The same structure is modeled with equivalent circuit, which includes electric and magnetic coupling with the line and inter-resonator coupling. Modified even/odd analysis is used to obtain scattering parameters from the equivalent circui

In this work, simple, low profile, compact quarter-mode substrate-integrated waveguide (QMSIW)-based antennas are proposed for Wireless Local Area Network (WLAN) at 5.2/5.5 GHz and Wireless Body Area Network (WBAN) at 5.8 GHz, respectively. By implementing QMSIW technique, the electrical size of the antenna is reduced up to 1/4th of the conventional circular SIW cavities. Thanks to the quarter mod

A printed multiband Multi-Input Multiple-Output (MIMO) antenna is proposed in this paper. This MIMO antenna system comprises two symmetric printed monopole antennas. Each antenna element consists of multiple bend lines, producing four resonant modes and covering the GSM900, PCS, LTE2300, and 5G bands. Simulated and measured results prove that the proposed MIMO antenna can be applied to traditional

This paper describes the design and characterization of a compact substrate integrated waveguide (SIW) fed antenna for the 122 GHz industrial, scientific, and medical band. The use of a single RO4350B substrate layer and the SIW feeding ensure a low-cost fabrication. Two versions of the antenna are presented differing in antenna gain and size. For measurement purpose, a transition from rectangular

In this paper, a compact, low-profile, coplanar waveguide-fed metamaterial inspired dual-band microstrip antenna is presented for Wireless Local Area Network (WLAN) application. To achieve the goal a triangular split ring resonator is used along with an open-ended stub. The proposed antenna has a compact size of 20 × 24 mm fabricated on an FR-4 epoxy substrate with dielectric constant () 4.4. The

This paper proposes a new radar cross section (RCS) reduced microstrip antenna incorporating 475 square slots on the patch. The proposed antenna achieves wideband RCS reduction with radiation performance sustained. The modified and reference antenna are simulated and analyzed in radiating and scattering mode, respectively. Prototypes of two antennas are fabricated and measured. Compared with the r

This paper presents a novel artificial magnetic conductor (AMC) loaded dipole above FR4 substrate. The proposed AMC consists of two metal layers that shield the wave from the lossy substrate leading to a significant increase in the dipole efficiency over a wide bandwidth. The dipole is fed through vias that are connected to a wideband balun placed on the opposite side of the ground plane. The prop

The pulse radiating characteristic of a wrapped bow-tie antenna (WBA) and wrapped resistively loaded bow-tie antenna (WRLBA) is presented for impulse radar applications in this paper. The numerical analysis of the WRLBA is performed by comparing that of the WBA. The wrapped antennas are realized on a flexible substrate. The antennas are fed by an impedance tapered balun, which has an overall trans

In this paper, a compact wideband tightly-coupled dipole antenna array has been developed. Dipole elements are placed in the triangular lattice to reduce the side lobe level in the radiation pattern of one of the planes. To obtain the initial dimensions, 1-D infinite array analysis of the proposed array is carried out. The infinite array is designed to operate in 5?14.3 GHz (96.3% impedance bandwi

The paper describes the design and development of a low profile wide scanned conformal active 1 × 32 phased array antenna for Ku-band SATCOM applications. The realized antenna is diagonally polarized and covers full transmit frequency band (i.e. 13.75?14.5 GHz) of Ku band SATCOM. All the developed sub-systems of the antenna, i.e. conformal radiating array, conformal transmit module, manifold netwo

A compact reconfigurable filtering ultra-wideband (UWB) antenna with switchable band-notched functions is proposed. The basic structure of the proposed design is a filtering slot antenna with good band-edge selectivity using stepped impedance resonator feeding line. The reconfigurability is achieved by using two microstrip lines paralleling to the feeding line and two PIN diodes. The reconfigurabl

The control of cutoffs is of great interest in designs of circular waveguides. In this paper, this topic is investigated for pure transverse-electric (TE) and transverse-magnetic (TM) modes by taking advantage of anisotropic reactance lining loadings. It is found that the cutoffs of TE and TM modes are determined by the reactance in the azimuthal and axial directions, respectively. When the reacta

The scattering of the H-polarized plane electromagnetic wave by a finite multilayer graphene strip grating is considered. The properties of the whole structure are obtained from the set of integral equations, which are written in the operator form. The scattering operators of a single layer are used and supposed to be known. Scattering and absorption characteristics as well as diffraction patterns

Microwave holography technique reconstructs a target image using recorded amplitudes and phases of the signals reflected from the target with Fast Fourier Transform (FFT)-based algorithms. The reconstruction algorithms have two or more steps of two- and three-dimensional Fourier transforms, which have a high computational load. In this paper, by neglecting the impact of target depth on image recon

The implementation of stable, accurate, and wideband second-order microwave integrators (SOMIs) is presented in this paper. These designs of SOMIs are obtained by using different combinations of transmission line sections and shunt stubs in cascading. Particle swarm optimization (PSO), cuckoo search algorithm (CSA), and gravitational search algorithm (GSA) are applied to obtain the optimal values

A new time reversal (TR) method for target imaging is proposed in this paper. Through single measurement by the antenna array, the received signals are utilized to form the space?frequency?frequency multistatic data matrix (MDM). Singular value decomposition is applied to the matrix to obtain the left singular vectors which span the signal subspace. The obtained vectors are divided into multiple s

In this paper, we propose a novel study of zero-index materials (ZIM) based on lumped element circuits using a wave concept iterative method (WCIP). This method is well used to demonstrate the behavior of zero-index-based microwave applications. This type of metamaterial can maintain the amplitude and the phase of an electromagnetic wave to be constant through the ZIM region, which is an important

In this paper, the patch-type frequency selective surfaces (FSS) based on substrate-integrated waveguide (SIW) technology is proposed to improve the bandwidth (BW) and angular performance. The proposed FSS configuration overcomes the limitations of both conventional 2D and 3D FSS structures. A closely coupled cascaded mechanism is employed to combine two identical FSS elements separated by thin di

In this paper, a miniaturized open-ended dual-band band-pass filter with stepped series capacitance and shunt meandered line inductance for microwave frequency applications has been designed and discussed. In order to offer ease of fabrication and uniplanar configuration, coplanar waveguide feeding arrangement has been used. Zeroth order resonance, a special phenomenon of composite right/left hand

This study introduces an alternative approach to the numerical solution of two-dimensional (2D) electromagnetic scattering problems by a numerical method of moments (MoM). The real source position vector is replaced by a complex quantity, then Green's function generates a complex source point beam, therefore the interactions between the far zone elements in the impedance matrix are neglected, exce

In this paper, two different radiating structures fed with modified L-probe, are reported using a circuit theory concept. The proposed antennas are operating in wireless local area network (WLAN) and universal mobile telecommunications system (UMTS) frequency bands. In the first design, an E-shaped patch is studied to increase the bandwidth. It is observed that the bandwidth is directly proportion