Wojciech Marynowski

Bio: Wojciech Marynowski is an academic researcher from Gdańsk University of Technology. The author has contributed to research in topics: Microstrip & Ferrite (magnet). The author has an hindex of 10, co-authored 43 publications receiving 211 citations.

An Analysis of Probe-Fed Rectangular Patch Antennas With Multilayer and Multipatch Configurations on Cylindrical Surfaces

Abstract: A multipatch configuration of probe-fed rectangular microstrip antennas mounted on a cylindrical body, with electrically small radius, with an arbitrary number of substrate and superstrate layers is investigated in this paper. A full-wave analysis and a moment-method calculation are employed. A unified procedure for creating proper matrices for the investigated geometry of the structure is outlined here. Numerical results for the input impedances and radiation patterns are calculated and verified by comparing them with results from the literature and our own measurements of manufactured prototypes.

Integrated Broadband Edge-Guided Mode Isolator With Antiparallel Biasing of the Ferrite Slabs

Abstract: In this letter, a novel configuration of the integrated waveguide edge-guide (EG) isolator, containing two antiparallelly biased ferrite slabs separated by a dielectric gap (DG), is reported. It is found that in this configuration the transmission losses are significantly lower than the ones observed in an EG mode isolator completely filled with ferrite (without a DG). The principle of operation of the proposed isolator is analyzed numerically and the obtained low losses originate from the wave transmitted in the gap. This behavior is also demonstrated using the prototype of this type of isolator working at 6.25 GHz, where simulated and measured results show isolation of 48 dB and insertion losses of 1.3 dB.

Design of UWB Coplanar Antenna with Reduced Ground Plane

Abstract: The paper presents the design of a compact ultra wideband antenna composed of two circular coplanar strips which enclose slot aperture of the similar shape. The antenna is fed with three coplanar strip-lines of 50 Ω. The effect of the outer strip edge on the antenna bandwidth is investigated. This antenna configuration has been modeled and experimentally tested, showing good performance in 1.7–15.5 GHz frequency range where return losses |S 11| < –10 dB are achieved. Stable radiation patterns across the whole band is also observed.

An Analysis of Elliptical-Rectangular Multipatch Structure on Dielectric-Coated Confocal and Nonconfocal Elliptic Cylinders

Abstract: A rigorous analysis of the resonance frequency problem of an elliptical-rectangular microstrip structure mounted on dielectric-coated elliptic conducting cylinder, with electrically small radius, is investigated in this paper. A full-wave analysis and a moment-method calculation are employed. The analysis is carried out considering the expansion of the field as a series of Mathieu functions. The complex resonance frequencies of the structure are studied. Modes suitable for antenna application are also investigated. Numerical results for the complex resonance frequency and radiation patterns are calculated and verified by comparing them with results from commercial software and our own measurements of manufactured prototypes. The difference between confocal and nonconfocal dielectric-coated elliptic cylinders is investigated.

Efficient Complex Root Tracing Algorithm for Propagation and Radiation Problems

Abstract: An efficient complex root tracing algorithm for propagation and radiation problems is presented. The proposed approach is based on a discretization of Cauchy’s Argument Principle and its generalization to the $\mathbb {C}\times \mathbb {R}$ space. Moreover, an engagement of the tracing process with a global root finding algorithm recently presented in the literature is performed. In order to confirm a validity and efficiency of the proposed technique, a few different types of structures have been analyzed.

IEEE Transactions on Microwave Theory and Techniques and Antennas and Propagation Announce a Joint Special Issue on Ultra-Wideband (UWB) Technology

Abstract: Before the emergence of ultra-wideband (UWB) radios, widely used wireless communications were based on sinusoidal carriers, and impulse technologies were employed only in specific applications (e.g. radar). In 2002, the Federal Communication Commission (FCC) allowed unlicensed operation between 3.1–10.6 GHz for UWB communication, using a wideband signal format with a low EIRP level (−41.3dBm/MHz). UWB communication systems then emerged as an alternative to narrowband systems and significant effort in this area has been invested at the regulatory, commercial, and research levels.

Design and Analysis of 24-GHz Active Isolator and Quasi-Circulator

Abstract: In this paper, a new topology using the common-source amplifier, which is a unilateral component and the directional coupler, is proposed to realize an isolator without ferrite. The theory and the design procedures are presented. The performance of this isolator is comparable to those of the ferrite isolators, except for the bandwidth. The 1-dB compression point of output power $({\rm OP}_{1{\rm dB}})$ of the insertion loss is high due to the passive nature of the directional coupler, but the reverse isolation deteriorates with the increasing input power. The proposed 24-GHz monolithic microwave integrated circuit isolator is developed in TSMC 180-nm CMOS. Based on the proposed isolators, a quasi-circulator is designed and fabricated. Both the isolator and quasi-circulator have better ${\rm OP}_{1{\rm dB}}$ of the insertion loss than reported active isolators and quasi-circulators.

Time-Domain Measurement of Time-Coded UWB Chipless RFID Tags

Abstract: Chipless ultra-wideband (UWB) has been proposed as a low-cost alternative for radiofrequency identiflcation (RFID). In this paper, a comprehensible theoretical introduction to time-domain operation of a UWB RFID tag is described, and a circuit model is proposed. For commercial applications low-cost RFID readers are demanded. To this end, this paper addresses the measurement of time-coded UWB chipless tags for RFID in time domain. Two difierent setups to detect time-coded tags are presented, one based on commercial UWB impulse radar (IR) and the other based on a vector network analyzer (VNA). The experimental results show the feasibility of using an IR-UWB radar as a UWB RFID reader, achieving very good read ranges.

Simulation and Experiment of a Compact Wideband 90 $^{\circ}$ Differential Phase Shifter

Abstract: A compact wideband 90° differential phase shifter is developed by modifying ports termination in the Abbosh phase-shifter configuration. This novel phase-shifter arrangement consists of a 3-dB directional coupler with the coupled and transmission ports terminated with reactive loads. The proper reactance is found at the input of the coupled line section in which the remaining ports are open circuited. Both coupled sections utilize a multilayer broadside coupling microstrip-slot-microstrip tight coupler. A theoretical model is presented to explain the performance of the proposed phase shifter and design procedure. Further, the phase shifter was designed and manufactured. Results of calculation and measurement show that the developed circuit provides a 90° differential phase shift with deviation less than ±4° across the 3-7-GHz frequency band.