In this study, a new microstrip patch antenna with wideband radar cross-section (RCS) reduction is presented. The RCS of the proposed antenna was reduced by subtracting the current-direction slots of the patch, with the radiation performance sustained not only for the current-direction subtraction, but also for the no modification in the ground plane. Modified and reference antenna were fabricated

In this paper, a triple-wideband bandpass filter (BPF) with controllable bandwidths based on two multi-mode stub-loaded resonators (MMSLRs) and a triple-mode resonator is presented. The MMSLR is loaded with two identical folded open-ended stubs and a T-shaped stub. Each passband of the tri-band BPF is formed by four resonant modes, which provide sufficient bandwidths to meet various application re

This paper presents a substrate-integrated waveguide (SIW) mixed electric and magnetic coupling structure implemented on a single-layer substrate to create finite transmission zeros (TZs), which can be used to design microwave filters with higher frequency selectivity. Mixed coupling is realized by three slot-lines on the top metal plane combined with an iris-window between two adjacent SIW caviti

A modified compact Y-junction substrate-integrated waveguide (SIW) four-way power divider (PD)/combiner is proposed in this paper. The proposed approach is based on the traditional Y-junction waveguide. By using direct transition structure from SIW to half-mode SIW, four-way PD that provides equal power split to all four output ports is achieved. The even- and odd-mode equivalent circuits are give

This paper presents an ultra-wideband coplanar waveguide (CPW)-to-asymmetric coplanar stripline (ACPS) transition based on aluminum nitride (AlN) substrate. The concepts of designing CPW, ACPS, and CPW-to-ACPS transition are explained. In order to suppress parasitic modes, vias going through AlN substrate are added along the ground traces. The signal trace is tapered out and chamfered to reduce th

In this paper, a self-actuated frequency-selective radome is presented and applied to a microstrip antenna. The radome acts as a self-triggered switchable screen to achieve adaptive electromagnetic protection in the L band. A prototype of the radome is fabricated to measure its transmission performance. The switchable characteristic is verified by a high-power radiation experiment carried out in a

In this paper, a novel class of balun bandpass filters is presented on slot-line resonator (SLR) toward intrinsic balanced performance in amplitude and phase. The proposed balun filter consists of three inductive-coupled SLRs in the middle, one single-ended unbalanced port, and one balanced port with two terminals. According to the distinct field conversion from the slotline to the microstrip feed

This paper discusses some significant design issues that are faced in resonant inductive system for wireless power transfer ?on the move?. The targeted system adopts a single AC source to power a sequence of transmitting () coils, placed along the path, whose geometry is optimized to minimize the variations of coupling for every possible position. To retain a constant coupling coefficient, two n

This paper presents a hexa-band frequency reconfigurable planar antenna, printed on a 1.6 mm thicker FR 4 substrate and backed by a truncated ground plane. The given antenna operates in four different frequency modes, depending on the state of the two lumped element switches. The proposed antenna works at six frequencies, 2.10, 2.40, 3.35, 3.50, 5.28, and 5.97 GHz. These frequency bands are dedica

This paper presents a new technique for the enhancement of axial ratio (AR) bandwidth of a circularly polarized dielectric resonator antenna with a single feeding. To enhance the AR bandwidth, adjacent 3-dB AR passbands are merged by inserting the notches and conductive coating in the dielectric resonator. The dimensions of the notches and conductive coating are selected in such manner that impeda

Microwave and millimeter-wave reflectometry is one of the potential techniques for the diagnosis and detection of biological abnormalities, such as subcutaneous masses or cancerous tumors in human body. In this paper, a high-quality microwave sensor based on planar misrostrip resonator is designed, fabricated, and successfully tested with different kinds of biological samples. The proposed sensor

The contribution of this paper is to propose a novel rat-race hybrid coupler of arbitrary coupling coefficient. Traditionally, the rat-race hybrid couplers are built by various loop-alike transmission-lines of multiple quarter-wavelength, and in this paper, we approach the coupler design by using a circular substrate integrated waveguide (SIW) cavity (SIWC). The employed SIWC supports two mutually

In this paper, theoretical/simulation study of specific absorption rate (SAR) and/or temperature distributions in a bi-layered bio-media (fat and muscle)/realistic tri-layered bio-media (skin, fat, and muscle layers) in direct contact with water-loaded metal diagonal horn (MDH) designed at 915 MHz are investigated. The effects of fat thickness on the input reflection coefficient, reflection coeffi

A compact coplanar waveguide (CPW)-fed circular polarization (CP)-antenna for new generation applications with dual bands filtering performance along with CP feature based on unit-cell semi-fractal is proposed in this paper. The CP-antenna privileges from semi-fractal radiator causes to have a miniaturized size. The stopped bands are designed to suppress the interference with present WLAN and ITU-

A novel shape penta-band microstrip patch antenna is presented in this paper. The proposed antenna shows five operating frequencies and can be used for various wireless applications, i.e. 2.58 GHz for non-direct line of sight, wireless Internet service providers, and compatible with Navini Networks; 3.17 and 3.42 GHz for WiMAX; 4 GHz for C-band application such as weather radar systems; and 5.3 GH

A compact and planar broadband circularly polarized (CP) eighth-mode substrate integrated waveguide (EMSIW) antenna is proposed in this paper. An isosceles right triangular waveguide with one electric sidewall (located on one of its catheti) and two magnetic sidewalls (located on the other two edges of the triangle) is presented to investigate the characteristics of the EMSIW. The closed-form mode

A simple multiple-input-multiple-output (MIMO) antenna with quad-band-notched characteristics for ultra-wideband (UWB) system is proposed and tested in the article. Based on two similar radiators, the UWB-MIMO system only occupies 22 mm × 28 mm. By etching an inverted L-like meander slot, two inverted L-shaped slots, and adding a C-shaped stub beside the feeding line, four notched bands are realiz

This paper presents a technique to increase the bandwidth in substrate integrated waveguide (SIW) cavity-backed antennas, inspired by the design of cavity filters. The proposed structure consists of a slot antenna backed by two cavities, located one on top of the other and coupled through a slot. To demonstrate the bandwidth increase, a standard cavity-backed SIW antenna, with a rectangular slot e

In this paper, the first reported waterproof inkjet-printed dual-band monopole antenna on the flexible organic paper substrate is presented. The antenna, which operates at 900 MHz and 2.4 GHz, is inkjet-printed on commercially available photopaper using conductive silver nano-particle ink. To protect it from ambient humidity, a 1 µm thick Parylene-C layer was deposited on top of the antenna. To ve

A simple closed-form analytical formula is proposed to compute the probe reactance of an equilateral triangular patch antenna. The variation of the probe reactance with the variation of antenna dimension, substrate electrical parameters, and probe location is examined thoroughly. The computed values employing the present model show excellent agreement with experimental and simulation results.