Smart Cylindrical Dome Antenna Based on Active Frequency Selective Surface

Abstract

In this paper, we proposed a beamforming antenna, which is realized using an omnidirectional antenna in the center surrounded by a cylindrical smart dome. The smart dome is made of 16 active frequency selective surface columns of which the amplitude and phase response can be continuously tuned by varying the bias voltages of the employed varactors. Thus, the performance of the proposed antenna could achieve higher gain, better nulling level, and more agility than many switch methods-based cylindrical reconfigurable antennas. Moreover, in order to overcome the unavailable analytical synthesis caused by complex mutual coupling between columns, we develop a genetic algorithm based optimization system and conducted a serial of experiments to evaluate the high-gain, nulling, continuously steering, and frequency-invariant ability. The results show that, during the frequency tunable range of the AFSS (2.0 GHz to 2.7 GHz), the antenna can offer an additional gain of up to 6.57 dB and nulling level of −56.41 dBi. For the high-gain modes, the −3 dB beam widths are 26°–34°, which offers enhanced angular resolution compared with other reported beam-sweeping work. Furthermore, the radiation pattern is continuously steerable.

Gain and Bandwidth Enhancement of Superstrate Loaded 2×2 Circular- Array Antenna for X-Band and RADAR Applications

“…Jing et al have fabricated and tested a flexible coplanar waveguide (CPW)-fed rotatable FSS antenna on a 0.25-mm-thick FR4 substrate. This antenna achieves a high 5.31 dBi gain and 1.35 GHz FBW enhancement [28]. Abraham and Suriyan have developed a proximity-fed hexagonal-shaped 2×2 tri-band microstrip array antenna that uses an H-shaped slotted defected ground structure for L-and S-band applications.…”

Double‐square and gridded‐square loop frequency‐selective surface in the K‐band

“…Frequency‐selective surfaces (FSSs) are widely used in quasi‐optical (QO) systems as spatial filters to separate signals in different frequency bands . Other applications may be found as sub‐reflectors, radomes, and wireless communication antenna . Owing to its periodic structure, an FSS exhibits not only frequency‐selective property, but also spatial filtering characteristic.…”

A Frequency-Tunable SRR-Adopted Two-Pole Waveguide Filter Operating below the Cutoff Frequency

“…Recently, frequency-tunable devices have been researched intensively for microwave applications, in an effort to meet the demands of numerous wireless services [1][2][3]. As well as frequency tunability, a microwave filter must be lightweight and compact [4].…”