1. Introduction TM01 mode horns were mainly employed as a reflector antenna feeds so as to achieve omni-directional coverage around the vertical axis[1][2]. When a shaped beam was designed in the vertical plane, low sidelobe characteristics became important[2]. A dielectric lens horn was introduced. In this paper, accurate radiation characteristics are calculated through FDTD analyses. As for a...

Abstract—Impulse response of an ultra wide band (UWB) antenna is one of the most important parameters, which in turn helps in deriving other important antenna parameters like gain, antenna factor etc. The excitation input pulse to the antenna is a Gaussian pulse of finite width, hence to get antenna impulse response, far zone electric field data needs to be deconvolve with the input excitation ...

A method to design a miniaturized two-element quasi-Yagi antenna (QYA) with size and gain requirements is presented for portable ultra high frequency (UHF) radio frequency identification (RFID) reader applications. The antenna consists of a driver dipole and a ground reflector, and these elements are serially connected with a coplanar strip line. The ends of both elements are folded back toward...

Reflectarray antennas composed of rectangular grooves with sub-wavelength holes on a metal plate are designed for millimeter-wave regions. All depths multiple in the reflectarray elaborately manipulated high-gain reflector. A hole each groove reduces mass antenna, which rarely affects re-radiated filed from groove. In this paper, we have demonstrated light and achieved 25%-light antenna compare...

Cost effective, new antenna technology is required to build the large collecting area being planned for the next generation of radio telescopes. The Large Adaptive Reflector (LAR) is a novel concept being developed in Canada to meet this challenge. A prototype with a 200-350m diameter reflector, operating up to 2 GHz with a bandwidth of 750 MHz is planned. With a collecting area up to ∼ 10% of ...

We describe here the construction and testing of an IRA with dual polarity. Four feed arms are evenly spaced around the reflector, and each channel consists of a pair of arms on opposite sides of the reflector. Each channel uses a standard balun to convert the 50-ohm input impedance to 200 ohms. Since the characteristic impedance of each channel is 400 ohms, there is a 2:1 impedance mismatch at...

One way to rtidiate m impulse-like waveform is to employ a TEM-fed paraboloidal reflector mtenna. Various performance features of this antenna, such as prcpulse, impulse amplitude, impulse width etc., h:~vcbeen an;dyzcd in the past ( 1 to 8]. It hos been obscrveci that the low frequency or Iatc-time pcrforrmmce of this fotm of an IRA is governed by the elecrnc and magnetic dipole morncnts. A kn...

This paper addresses the design of a 60-GHz shaped reflector antenna that has to illuminate a predefined circular area without substantial spatial variation. At the boundary of this coverage area, the field strength has to fall off rapidly. Such efficient and confined illumination may be required in wireless networks that have to cope with a stringent link budget and/or require low channel disp...