This paper presents a modal-expansion analysis of the electromagnetically coupled coaxial dipole antenna. The analysis of the antenna problem is initially simplified using the even-odd mode excitation and then the resultant half structure is divided into two parts; one is the characterization of a coaxial feeding network and the other is the modeling of a sleeve monopole antenna driven by a coa...

Planar antennas based on tightly coupled dipole arrays (also known as a current sheet antenna or CSA) are amenable for use as electronically scanned phased arrays. They are capable of performance nearing a decade of bandwidth. These antennas have been demonstrated in many implementations at frequencies below 18 GHz. This paper describes the implementation using a relatively new multi-layer micr...

Abstract—A printed Log-periodic dipole array (LPDA) is presented, operating over the C, X and Ku bands. The antenna feeding structure consists of two coaxial cables, in order to realize an infinite balun which provides the required broadband input matching. The second coaxial cable mirrors the first one, connected to the antenna input, and is capable of both stabilizing the antenna phase center...

In the fifth-generation (5G) wireless communications, due to advantages such as wide range and low cost, sub-6 frequency band is widely used. It a challenge develop antennas for base stations which are band, high gain compact. this paper, center-fed collinear antenna array with compact size developed based on turnstile antenna. Non-uniform dipole has been used achieve broadband so that disadvan...

This paper presents design procedure of a spatial fading emulator representing a Laplacian angular power spectrum of incoming wave applicable to the over-the-air (OTA) evaluation for a handset MIMO antenna. The emulator has a number of antenna probes located on a circle around a handset under tested. The radius of the circle arranging the antenna probes can be defined by the power ratio of wave...

In this paper, circular and hexagonal array geometries for smart antenna applications are compared. Uniform circular (UCA) and hexagonal arrays (UHA) with 18 half-wave dipole elements are examined; also planar (2 concentric rings of radiators) uniform circular (PUCA) and hexagonal arrays (PUHA) are considered. The effect of rotating the outer ring of the PUCA is studied. In our analysis, the me...

Antennas radiate (vector) momentum as well as energy, but if the radiation pattern is symmetric, the total radiated momentum is zero. Consider a simple antenna array that consists of two short linear dipole antennas whose centers are λ/4 apart and whose conductors point along the line of centers of the antennas. If the two antennas are excited with a 90◦ phase difference, deduce the asymmetric ...

in this paper, a resonant slotted waveguide array antenna with circular boundary has been designed and simulated for mono-pulse airborne radar applications. the antenna parameters are:11% bandwidth in x-band (8.6-9.6ghz),vswr < 2, 38dbi directivity, sidelobes level of - 20db and 3-db beam-widths of 2.1degree. to design this antenna, it is divided into short sections (sub-arrays) each with a uni...

This article presents a phased array antenna employing MEMS phase shifter. The proposed phased array antenna consists of eight square patch antennas operating at 10.4 GHz with a bandwidth of 400 MHz. Feed line for each patch passes through a MEMS phase shifter realized by a series of bridges above the transmission line. The distance between the bridge and the transmission line underneath it is ...