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Ultra-wideband coplanar waveguide-to-asymmetric coplanar stripline transition from DC to 165 GHz

Author: Yunfeng Dong, Tom K. Johansen, Vitaliy Zhurbenko

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

Design and realization of a self-actuated frequency-selective radome integrated with microstrip antenna

Author: Qihui Zhou, Peiguo Liu, Bo Yi, Dingwang Yu

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

Balun bandpass filter on slot-line resonators with intrinsic balanced performance in amplitude and phase

Author: Lin-Ping Feng, Lei Zhu

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

Criticality mitigation in a quasi-constant coupling position independent resonant IPT network

Author: Alex Pacini, Franco Mastri, Diego Masotti, Alessandra Costanzo

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

A multi-band switchable antenna for Wi-Fi, 3G Advanced, WiMAX, and WLAN wireless applications

Author: Sadiq Ullah, Shaheen Ahmad, Burhan A. Khan, James A. Flint

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

Axial ratio bandwidth enhancement of a circularly polarized rectangular dielectric resonator antenna

Author: Gaurav Varshney, V. S. Pandey, R. S. Yaduvanshi

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

Detection of biological abnormalities using a near-field microwave microscope

Author: Fatemeh Kazemi, Farahnaz Mohanna, Javad Ahmadi-Shokouh

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

Novel rat-race coupler design of arbitrary coupling coefficient using substrate integrated waveguide cavity

Author: Min-Hua Ho, Yi-Hao Hong, Jen-Chih Li

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

Bi-layered/tri-layered bio-media in direct contact with metal diagonal horn for hyperthermia

Author: Soni Singh, Bhagirath Sahu, S. P. Singh

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

WiMAX and C bands semi-fractal circularly polarized antenna with satellite bands filtering properties

Author: T. Sedghi, T. Aribi, A. Kalami

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-