Reflective array antenna

About: Reflective array antenna is a research topic. Over the lifetime, 4366 publications have been published within this topic receiving 57884 citations.

An Efficient Pattern Synthesis Method for Cylindrical Phased Array Antennas

Abstract: An efficient approach for calculating the far field pattern of conformal phased array antennas mounted on cylindrical-shaped platforms is proposed. The array structure is taken into account by using an active element pattern technique, and the array is analyzed by using an element-by-element approach. The effects of all mutual couplings in the array environments are considered rigorously, and the efficiency of the proposed method is validated by using the commercial full-wave simulation software HFSS. Finally, a low side-lobe cylindrical phased array is designed for engineering by optimizing phases and amplitudes of port excitations.

Recent advances on space multibeam antennas based on a single aperture

Abstract: The objective of this work is to provide an overview on recent ESA developments on multibeam satellite antennas generating a multiple spot beams coverage with a single aperture. In particular, solutions based on a single oversized reflector, direct radiating arrays, active discrete lenses, and confocal reflectors will be discussed. They represent interesting solutions with respect to the architecture based on three or four reflectors which is still considered today the reference solution. ESA is supporting since several years activities in this challenging domain.

Experimental Study on the Dependence of Antenna Type and Polarization on the Link Reliability in On-Body UWB Systems

Abstract: An experimental study on the use of ultra-wideband antenna systems (3.5–4.5 GHz) on the human body for wireless body area network (WBAN) applications is conducted. It has been found that the link reliability can be improved and transmit power can be reduced by properly selecting the transmit and receive antennas with different radiation properties (omni-directional, directional, pattern diversity) and polarizations (vertical and horizontal) at each location on the body. Moreover, when there is blockage by the body, it may be possible to achieve better transmission when the antennas are horizontally polarized. Also, antennas with pattern diversity can be used to enhance the overall reliability of the communication system. In order to eliminate the use of cables in the measurements, an on-body UWB system has been developed and the reliability can be assessed more practically in terms of the peak amplitude of the received waveform and the bit error rate. It has been observed that when the link quality is improved, the transmit power can be reduced by more than 20 dB without compromising on the reliability, which will conserve the battery power.

Ultrawide band active radar array antenna for unmanned air vehicles

Abstract: The development of highly efficient, optically activated, semiconductor switches will yield compact radar transmitters that can be applied to airborne surveillance missions on unmanned air vehicles. Radar systems employing these high peak power sources must use ultrawide band antenna elements to efficiently meet system performance requirements. Unfortunately nearly all antenna elements that can meet the bandwidth requirements are undesirable for the airborne application because of their geometry and orientation necessary to utilize the maximum directivity. The equiangular spiral is a planar element which is suitable for the airborne application. This paper presents a heuristically derived expression for the transient radiation from this antenna and examines the performance of an ultrawide band active array composed of equiangular spiral elements, including beam forming and compensation of the waveform dispersion introduced by the spiral. >

Optimal number of array faces for active phased array radars

Abstract: The number of array faces is an important factor in determining antenna and radar system performance, cost, and manufacturing complexity. The subject of determining the optimum number of antenna faces has been addressed previously by several authors (Knittel,1965) using various figures of merit. For active phased array radars performing tracking and discrimination functions, the important figure of merit for antenna performance is power-aperture-gain (PAG) product. We determine the optimal number of faces by choosing PAG product as the figure of merit for the same tracking and discrimination performance at maximum scan angles. Given equal antenna performance at maximum scan angles in the coverage area, cost is the primary basis for comparison in the selection of the number of faces for a modern active phased array radar system.