266 research outputs found
Reconfigurable Reflectarrays and Array Lenses for Dynamic Antenna Beam Control: A Review
Advances in reflectarrays and array lenses with electronic beam-forming
capabilities are enabling a host of new possibilities for these
high-performance, low-cost antenna architectures. This paper reviews enabling
technologies and topologies of reconfigurable reflectarray and array lens
designs, and surveys a range of experimental implementations and achievements
that have been made in this area in recent years. The paper describes the
fundamental design approaches employed in realizing reconfigurable designs, and
explores advanced capabilities of these nascent architectures, such as
multi-band operation, polarization manipulation, frequency agility, and
amplification. Finally, the paper concludes by discussing future challenges and
possibilities for these antennas.Comment: 16 pages, 12 figure
A Continuous Beam Steering Slotted Waveguide Antenna Using Rotating Dielectric Slabs
The design, simulation and measurement of a beam steerable slotted waveguide
antenna operating in X band are presented. The proposed beam steerable antenna
consists of a standard rectangular waveguide (RWG) section with longitudinal
slots in the broad wall. The beam steering in this configuration is achieved by
rotating two dielectric slabs inside the waveguide and consequently changing
the phase of the slots excitations. In order to confirm the usefulness of this
concept, a non-resonant 20-slot waveguide array antenna with an element spacing
of d = 0.58{\lambda}0 has been designed, built and measured. A 14 deg beam
scanning from near broadside ({\theta} = 4 deg) toward end-fire ({\theta} = 18
deg) direction is observed. The gain varies from 18.33 dB to 19.11 dB which
corresponds to the radiation efficiencies between 95% and 79%. The side-lobe
level is -14 dB at the design frequency of 9.35 GHz. The simulated co-polarized
realized gain closely matches the fabricated prototype patterns
Compact broadband electronically controllable SIW phase shifter for 5G phased array antennas
This work presents a novel compact and broadband electronically controllable substrate integrated waveguide (SIW) phase shifter intended for beamsteering applications in antenna arrays for 5G wireless communication. The proposed phase shifter is designed to operate over a large bandwidth (26 GHz–32 GHz) with a simulated maximum insertion loss of less than 3 dB and a maximum phase difference of more than 100°+5° over the entire band. The phase shift is provided via metal posts which are switched between capacitive and inductive loading through beam-lead PIN diodes
3D BEAMSTEERING LOW COMPLEXITY RECONFIGURABLE MULTILEVEL ANTENNA
The main idea of the thesis is to develop a new reconfigurable antenna that makes beamsteering in 3D, with the minimum number of possible switches (maximum 9) and as simple as possible for use in a car vehicle. The design will explore an active dipole located in the center of the antenna (which is fed by a tapered balun), and 4 parasitic dipoles around, placed so that the steering can be done in 9 3D directions according to which parasites we activate by means of switches. The basic idea is to study the physical principle of double reflection, the first reflection due toBeamforming, in its many variants, is a key spatial processing technique to improve user throughput, system capacity, system coverage as well as reducing interference. Simple architectures enabling beamforming either in predefined or arbitrary directions are very desirable for the Fifth Generation of Mobile Communications (5G) to boost power efficiency. Furthermore, it is expected that the number of 5G mobile subscribers grows from 5 million in 2019 to nearly 600 million by 2023, increasing traffic, connections density, and latency which will increase the demand of capacity to the network. Therefore, a broadband intelligent antenna must be at the basis to provide reliable data service, capable to adapt the antenna's capabilities to environment changes. The scope of this thesis focuses on a novel multilevel reconfigurable antenna incorporating beamsteering capabilities by using the lowest number of switches possible
10 GHz Low Loss Liquid Metal SIW Phase Shifter for Phased Array Antenna
This paper presents a proof of concept demonstrator for a pair of novel phase shifters based on substrate integrated waveguide (SIW) technology. Gallium-based liquid metal (LM) is used to reconfigure each phase shifter. The paper presents LM phase shifters that, for the first time, have a phase shifting range of 360⁰. The phase shifters have a small electrical size, and they are intended for use within phased array antenna applications. The paper also presents a design procedure for the phase shifters. The procedure has been used to design two phase shifters operating at 10 GHz. The design process can be readily scaled for operation at other frequencies. The proposed phase shifters are reciprocal and bidirectional and they have very low insertion loss. A series of reconfigurable LM vias are used to achieve the phase shift. Each of LM via is activated once a drill hole is filled with LM and it is deactivated once LM is removed. Using this method; it is possible to achieve a phase shift step ranging from 1° to 100° using a single LM via. Moreover, the overall phase shift can be extended to 360° by employing several LM vias in series inside the SIW. The proposed phase shifters have an insertion loss lower than 3 dB and provide a total phase shifting range of approximately 360° in eight steps of approximately 45° each. This enables the proposed two phase shifters to have an extraordinary Figure of Merit (FoM) of 131.3 ⁰/dB and 122.4 ⁰/dB
Antenna frequency and beam reconfliguring using photoconducting switches
This paper presents the use of photoconducting switches in antennas for reconfiguring operating frequencies and radiation patterns. It has also been demonstrated that these switches can be used in optically controlled phase shifters. A frequency shift of 40% is achieved with a dipole antenna and an array of patch antennas show beam scanning covering 30deg
Advances in Reconfigurable Antenna Systems Facilitated by Innovative Technologies
© 2013 IEEE. Future fifth generation (5G) wireless platforms will require reconfigurable antenna systems to meet their performance requirements in compact, light-weight, and cost-effective packages. Recent advances in reconfigurable radiating and receiving structures have been enabled by a variety of innovative technology solutions. Examples of reconfigurable partially reflective surface antennas, reconfigurable filtennas, reconfigurable Huygens dipole antennas, and reconfigurable feeding network-enabled antennas are presented and discussed. They represent novel classes of frequency, pattern, polarization, and beam-direction reconfigurable systems realized by the innovative combinations of radiating structures and circuit components
ELECTRONICAL LY RECONFIGURABLE FS S - INSPIRED TRANSMITARRAY FOR TWO DIMENS IONAL BEAMSTEERING FOR 5G ANDRADAR APPL ICATIONS AT 2 8 GHZ
In this dissertation, the author’s work on a 28 GHz transmitarray capable of antenna
beamsteering for various wireless applications, is presented. Such device allows for
the adjustment of the radiation pattern of an antenna by changing its main lobe
direction, without the need of any mechanical means.
A unit-cell based on a square-slot Frequency Selective Surface (FSS) is designed,
simulated and optimised through several full-wave simulations, using an electromagnetic
solver (CST MWS). Subsequently, the unit-cell was extended to a 10x10 array
configuration in order to enable Two-dimensional (2D) beamsteering. This work
yielded the fabrication of a prototype composed of four passive transmitarray lens,
which were experimentally tested and characterised. Finally, a novel unit-cell based
on a double square-slot intended aiming at active beamsteering was also studied
and optimised in simulation environment.
From this work, it was demonstrated that transmitarray can be seen as feasible
alternative to many traditional beamsteering techniques, such as phased antenna
arrays, while reducing the RF burden of the overall system using only a single
radiation source. This fact, allied with it’s ease of integration, reduced cost and
low-profile characteristics make transmitarrays a desirable solution for 5G and
RADAR applications, among others
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