Design of a Reconfigurable Reflectarray Unit Cell for Wide Angle Beam-Steering Radar Applications

An electronically tunable reflectarray element is proposed in this work to design beam-steering antennas useful for radar applications. A reduced size reflectarray unit cell is properly synthesized in order to extend the antenna beam scanning capabilities within a wider angular region. The radiating structure is accurately optimized to provide a full phase tuning range by adopting a single varactor load as phase shifter element. A 0.46λ-reflectarray cell is designed at the frequency of 11.5 GHz, obtaining a phase agility of about 330°. The cell is successfully adopted for the design of a21 × 21reconfigurable reflectarray. The antenna is numerically tested for different configurations of the varactors capacitance values, and good beam-steering performances are demonstrated within a wide angular range.

Download Full-text

Wide-Angle Beam Steering AESA with Three-Dimensional Stacked PCB for Ka-Band In-Flight Connectivity

2019 IEEE International Symposium on Phased Array System & Technology (PAST) ◽

10.1109/past43306.2019.9020998 ◽

2019 ◽

Cited By ~ 1

Author(s):

Tomohiro Takahashi ◽

Katsuyuki Yamamoto ◽

Tatsuya Sakamoto ◽

Hiroshi Suzuki ◽

Hitoshi Arai ◽

...

Keyword(s):

Beam Steering ◽

Three Dimensional ◽

Wide Angle ◽

Ka Band

Download Full-text

A Design Approach of Optical Phased Array with Low Side Lobe Level and Wide Angle Steering Range

Photonics ◽

10.3390/photonics8030063 ◽

2021 ◽

Vol 8 (3) ◽

pp. 63

Author(s):

Xinyu He ◽

Tao Dong ◽

Jingwen He ◽

Yue Xu

Keyword(s):

Phased Array ◽

Phase Distribution ◽

Beam Steering ◽

Side Lobe ◽

Design Approach ◽

Optical Antennas ◽

Side Lobe Level ◽

Wide Angle ◽

Spacing Distribution ◽

Optical Phased Array

In this paper, a new design approach of optical phased array (OPA) with low side lobe level (SLL) and wide angle steering range is proposed. This approach consists of two steps. Firstly, a nonuniform antenna array is designed by optimizing the antenna spacing distribution with particle swarm optimization (PSO). Secondly, on the basis of the optimized antenna spacing distribution, PSO is further used to optimize the phase distribution of the optical antennas when the beam steers for realizing lower SLL. Based on the approach we mentioned, we design a nonuniform OPA which has 1024 optical antennas to achieve the steering range of ±60°. When the beam steering angle is 0°, 20°, 30°, 45° and 60°, the SLL obtained by optimizing phase distribution is −21.35, −18.79, −17.91, −18.46 and −18.51 dB, respectively. This kind of OPA with low SLL and wide angle steering range has broad application prospects in laser communication and lidar system.

Download Full-text

Characterization of Tiled Architecture for C-Band 1-Bit Beam-Steering Transmitarray

Sensors ◽

10.3390/s21041259 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1259

Author(s):

Dmitry Kozlov ◽

Irina Munina ◽

Pavel Turalchuk ◽

Vitalii Kirillov ◽

Alexey Shitvov ◽

...

Keyword(s):

Communication Systems ◽

Beam Steering ◽

Unit Cell ◽

Electromagnetic Simulations ◽

Fifth Generation ◽

Full Wave ◽

Array Architecture ◽

Modulation Pattern ◽

Good Agreement

A new implementation of a beam-steering transmitarray is proposed based on the tiled array architecture. Each pixel of the transmitarray is manufactured as a standalone unit which can be hard-wired for specific transmission characteristics. A set of complementary units, providing reciprocal phase-shifts, can be assembled in a prescribed spatial phase-modulation pattern to perform beam steering and beam forming in a broad spatial range. A compact circuit model of the tiled unit cell is proposed and characterized with full-wave electromagnetic simulations. Waveguide measurements of a prototype unit cell have been carried out. A design example of a tiled 10 × 10-element 1-bit beam-steering transmitarray is presented and its performance benchmarked against the conventional single-panel, i.e., unibody, counterpart. Prototypes of the tiled and single-panel C-band transmitarrays have been fabricated and tested, demonstrating their close performance, good agreement with simulations and a weak effect of fabrication tolerances. The proposed transmitarray antenna configuration has great potential for fifth-generation (5G) communication systems.

Download Full-text

Design of an Active Beam Steering Array with a Perforated Wide-Angle Impedance Matching Layer

IEEE Transactions on Antennas and Propagation ◽

10.1109/tap.2021.3073984 ◽

2021 ◽

pp. 1-1

Author(s):

Juho Yun ◽

Daesung Park ◽

Donghyuk Jang ◽

Keum Cheol Hwang

Keyword(s):

Beam Steering ◽

Impedance Matching ◽

Wide Angle ◽

Matching Layer

Download Full-text

Wide-angle, high-resolution three-dimensional (3D) imaging using non-mechanical beam steering

Unconventional Imaging and Adaptive Optics 2021 ◽

10.1117/12.2597229 ◽

2021 ◽

Author(s):

Christopher L. Hoy ◽

Jay Stockley ◽

Kelly Kluttz ◽

Doug McKnight ◽

Lance Hosting ◽

...

Keyword(s):

High Resolution ◽

3D Imaging ◽

Beam Steering ◽

Three Dimensional ◽

Wide Angle

Download Full-text

Combining solution wide-angle X-ray scattering and crystallography: determination of molecular envelope and heavy-atom sites

Journal of Applied Crystallography ◽

10.1107/s0021889809003094 ◽

2009 ◽

Vol 42 (2) ◽

pp. 259-264 ◽

Cited By ~ 3

Author(s):

Xinguo Hong ◽

Quan Hao

Keyword(s):

Structure Determination ◽

Heavy Atom ◽

Unit Cell ◽

Wide Angle ◽

X Ray ◽

X Ray Scattering ◽

Molecular Envelope ◽

Waxs Data ◽

Ray Scattering

Solving the phase problem remains central to crystallographic structure determination. A six-dimensional search method of molecular replacement (FSEARCH) can be used to locate a low-resolution molecular envelope determined from small-angle X-ray scattering (SAXS) within the crystallographic unit cell. This method has now been applied using the higher-resolution envelope provided by combining SAXS and WAXS (wide-angle X-ray scattering) data. The method was tested on horse hemoglobin, using the most probable model selected from a set of a dozen bead models constructed from SAXS/WAXS data using the programGASBORat 5 Å resolution (qmax= 1.25 Å−1) to phase a set of single-crystal diffraction data. It was found that inclusion of WAXS data is essential for correctly locating the molecular envelope in the crystal unit cell, as well as for locating heavy-atom sites. An anomalous difference map was calculated using phases out to 8 Å resolution from the correctly positioned envelope; four distinct peaks at the 3.2σ level were identified, which agree well with the four iron sites of the known structure (Protein Data Bank code 1ns9). In contrast, no peaks could be found close to the iron sites if the molecular envelope was constructed using the data from SAXS alone (qmax= 0.25 Å−1). The initial phases can be used as a starting point for a variety of phase-extension techniques, successful application of which will result in complete phasing of a crystallographic data set and determination of the internal structure of a macromolecule to atomic resolution. It is anticipated that the combination ofFSEARCHand WAXS techniques will facilitate the initial structure determination of proteins and provide a good foundation for further structure refinement.

Download Full-text