IEEE Antennas and Propagation Magazine

This article will deal with the impact of mutual coupling on the far-field peak sidelobe performance of a finite planar phased-array antenna having a circular aperture shape and containing 2,066 elements arranged in a triangular grid. The radiator that is used is of the open-ended rectangular waveguide type, vertically polarized. The computation of the far-field performance of the array antenna is... View full abstract»

The growing demand for low-profile, efficient compact antennas with reconfigurable characteristics has prompted antenna engineers to use novel materials in place of conventional dielectrics. Magnetodielectric materials combining both dielectric and magnetic properties have been widely investigated. In this article, we present a comprehensive literature study that examines the advantages and limita... View full abstract»

An examination of a new kind of rectangular dielectric resonator antenna (DRA) demonstrates that it delivers better gain and radiation efficiency for operating in the Worldwide Interoperability for Microwave Access (Wi-MAX) (3.3-3.7 GHz) band. The new dual-mode wideband circularly polarized (CP) DRA is implemented by using a stair-shaped microstrip feed line, a pair of L-shaped slots in the ground... View full abstract»

Existing dual-polarization antennas are categorized into three separate groups according to their topologies. Various cross-coupling mechanisms between orthogonal polarizations are specifically discussed in three categories and related to port isolation and cross-polarization radiation. Some representative antennas of each group are presented, and their performance is compared in terms of port iso... View full abstract»

In ultradense networks (UDNs), finding an omnidirectional, yet orthogonally polarized, antenna in a reasonable size has been a challenge. We have developed an antenna type that appears to address this need. These antennas, which operate in pairs, offer enhanced polarization characteristics and can be scaled to operate at different frequencies. Moreover, the gain of each antenna, and thus the pair,... View full abstract»

The free-space Friis equation is often used in a half space over a conducting ground plane, sometimes with erroneous results. In this article, corrections for the Friis equation are shown for several ground-plane cases. This article also offers an explanation for the previously misunderstood 6-dB puzzle in the monopole-to-monopole case. View full abstract»

Most existing rain attenuation prediction models are tested only at 55 GHz. Few W-band models have been tested, and these models present problems associated with high complexity and cannot predict with high accuracy in the short term. A dynamical short-term prediction method is proposed here, and it has a simpler structure and higher accuracy than previous rain attenuation models and can theoretic... View full abstract»

A smaller microstrip antenna design is essential for current and future wireless applications. For the design proposed in this article, researchers achieved size reduction when a circular microstrip patch is loaded with a metamaterial structure using a complementary split ring resonator (CSRR) with partially loaded nonuniform metasurfaces (NUMSs) on a ground plane. The designed antenna achieved a ... View full abstract»

A framework is presented to investigate the leading causes that determine deviations between simulation and measurement results in circularly polarized (CP) antennas operating in the millimeter-wave (mm-wave) range. For mm-wave antennas in general and CP antennas in particular, the whole validation procedure is considered to be especially challenging. The mechanical differences between the applica... View full abstract»

This article presents a hardware-based courseware package for use in teaching transmission line (Tline) theory. The hardware components include large inductors and capacitors that are used to slow down the speed of signals in the Tline and LEDs to allow the slowed-down signals to be observed by the human eye. This courseware can be used to augment the laboratory work in electromagnetic courses tha... View full abstract»