Lev Pazin

Multiband Flat-Plate Inverted-F Antenna for Wi-Fi/WiMAX Operation

A printed multiband flat-plate inverted-F antenna (IFA) is presented. The antenna is complexly structured and can operate as an internal laptop antenna over multiple Wi-Fi and WiMAX frequency bands. The antenna was studied by means of numerical simulations. The predicted achievable -10 dB return loss bandwidth of the antenna is confirmed and demonstrated by experimental measurements.

Reconfigurable Slot Antenna for Switchable Multiband Operation in a Wide Frequency Range

A reconfigurable antenna with switchable multiband functionalities is presented. The antenna operates one at a time at five adjacent frequency subbands in the upper ultrawideband (UWB) frequency band of 6.0-10.6 GHz. The switching from one subband to another is done electronically by means of five PIN diode switches. The antenna also has a nearly omnidirectional radiation pattern, with vertical polarization at each of its frequency subbands. Simulated and measured results are compared and are shown to be in good agreement.

Inverted-F Laptop Antenna With Enhanced Bandwidth for Wi-Fi/WiMAX Applications

A novel printed multiband inverted-F antenna (IFA) for laptop computers is presented. The antenna has a simple structure and it is sufficiently narrow to easily fit on each side of the housing of the display unit of the laptop. The antenna is designed to operate in all the allocated Wi-Fi and WiMAX frequency bands while providing near omnidirectional coverage in the horizontal plane. The multiband performance of the proposed antenna and its omnidirectionality are validated by measurements.

A Compact 60-GHz Tapered Slot Antenna Printed on LCP Substrate for WPAN Applications

We describe a compact endfire 60-GHz tapered slot antenna (TSA), which is printed on a low-permittivity liquid crystal polymer (LCP) substrate. The antenna features a novel wideband collinear microstrip-to-slot transition, which is of smaller size compared to other transitions. This antenna can be integrated with a RF module for use in future wireless personal area network (WPAN) applications. Such an antenna can be used both as an individual radiator as well as an element of antenna array. The antenna also features a fork-shaped metallic carrier, which gives it good rigidity. In addition, the antenna features a metallic reflector, which increases its directive gain. Numerical simulations show that the operating frequency band of the antenna is from 53.3 to 69.6 GHz (greater than 25% bandwidth) and that the directive gain of the antenna within its operating frequency range 57-66 GHz is between 6.8 and 9.9 dB.

Narrow-Size Multiband Inverted-F Antenna

We present a narrow-size multiband inverted-F antenna (IFA), which can easily fit inside the housing of display units of ultra-slim laptops. The narrowness of the antenna is achieved by allowing some of its metallic parts to extend over the sidewalls of the dielectric substrate. The antenna is aimed to operate in all the allocated WiFi and WiMAX frequency bands while providing near-omnidirectional coverage in the horizontal plane. The multiband performance of the proposed antenna and its omnidirectionality are validated by measurements.

Errata to “Dual Frequency and Dual Circular Polarization Microstrip Nonresonant Array Pin-Fed From a Radial Line”

A new type of a dual frequency and dual circular polarization multilayer microstrip nonresonant antenna array for satellite communication is presented. The microstrip radiating elements in the array are arranged in concentric circles and fed through pins embedded in a radial line. The radial line is excited through a probe at its center. The microstrip array exhibits a dual frequency band of operation, low side-lobes in the radiation pattern, and high radiation efficiency (more than 65%) for both polarizations. The microstrip element has been designed using commercial software based on the method of finite integral time domain algorithm, and the feed network has been designed by a theoretical analysis. A prototype of the array has been built and tested. The agreement between the measured and numerical results is satisfactory.

Reconfigurable Rotated-T Slot Antenna for Cognitive Radio Systems

A novel reconfigurable slot antenna for the upper ultra wideband frequency range is presented. The antenna can operate at any of eight adjacent sub-bands in the 6.0-10.6 GHz frequency band, and is configured by means of seven PIN diode switches. At each of its sub-bands, the antenna provides a nearly omnidirectional radiation pattern in the horizontal plane, with predominantly vertical polarization.

Quasi-Isotropic X-Band Inverted-F Antenna for Active RFID Tags

An X-band (10.5 GHz) inverted-F antenna (IFA) for an active radio frequency identification (RFID) tag is presented. The antenna consists of two parts. One part comprises a driven monopole and a ground plane. The second part is a metal casing mounted on the ground plane to provide enclosed space for housing the electronics of the tag. The antenna was studied by means of both numerical simulations and measurements. The numerical simulations reveal that the radiation pattern of the antenna is quasi-isotropic. They also show that the -10-dB return loss bandwidth of the antenna is nearly 15%. This predicted antenna bandwidth value has been confirmed by experimental measurement.

ON REDUCING THE PHASE ERRORS IN THE APERTURE OF A RADIAL WAVEGUIDE PIN-FED NON-RESONANT ARRAY ANTENNA

With a proper design, the aperture field of a conventional radial waveguide pin-fed non-resonant array antenna (RWPFAA) can be rendered equiphase at a given central frequency. However, when the operating frequency deviates from this central frequency, the aperture field will exhibit an undesired conical phase error. To alleviate this problem, we propose a novel design in which the frequency-dependent aperture phase error distribution is rendered serrated. The gain and side-lobes of an RWPFAA with serrated phase error distributions are studied by resorting a simple model of a line source as well as a more representative model of a circular aperture. The theoretical results are supplemented by numerical data. Schemes of RWPFAAs comprising two and three sections, which render the phase error distribution in the antenna aperture serrated, are suggested.

On the matching characteristics of a rectangular slot located near the edge of a finite-size ground plane

We study the matching characteristics of a rectangular slot located in the farthest upper part of a ground plane. First, we investigate the effect of geometrical parameters including the length and width of the slot, the ground plane height, and feed point position on the input impedance. In turn, we consider the matching between the slot and a feed and examine impedance-matched frequencies and bandwidths. An approximate closed-form expression for the impedance-matched wavelength of the slot in terms of its length, width, and feed-point position is given. The results can aid in the design of application-specific slot antennas for handheld devices.