1-Bit wideband 14 × 14 reconfigurable reflectarray with steady beam scanning at Ku-band

In this article, we propose an ultralow-power-consumption reconfigurable reflectarray antenna (RRA) capable of wide-angle beam scanning and simultaneous phase, amplitude, and polarization control. The RRA element is integrated with two single-pole single-throw (SPST) switch chips, which achieve 1-bit phase shift and continuous amplitude control for both <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i>- and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</i>-polarizations. By independently biasing each element, the RRA enables wide-angle electronic beam scanning in both polarization channels. Flexible beam phase control is achieved by adjusting the reference phase in the array factor. The beam amplitude is continuously tuned by precisely controlling the bias voltages of the integrated SPST switch chips. Furthermore, since both the phase and amplitude of the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i>- and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</i>-polarizations can be modulated, the RRA can synthesize scanning beams with arbitrary polarization. As a demonstration, a 16 × 16 RRA prototype is designed, simulated, and measured. Both simulations and measurements confirm that the RRA can achieve beam scanning over a wide-angle range of ±60°, with a maximum gain of 20.78 dBi and an aperture efficiency of 22.8%. Additionally, its capacities for phase, amplitude, and polarization control are fully demonstrated. Furthermore, the measured maximum power consumption of the RRA is only 0.34 W, corresponding to 1.3 mW per element. With its ultralow power consumption and versatility, the proposed RRA shows great potential for green wireless communications and advanced radar applications.

In this paper, an electronically 1‐bit reconfigurable reflectarray antenna (RRA) with wide‐angle beam‐scanning and high efficiency performance is presented for formation satellite communication applications. A 1‐bit phase distribution can be generated by controlling the state of the PIN dipole in the configurable element comprising a double split ring (DSR) patch and two T‐shaped parasitic structures. The resonant frequency of the DSR patch in both states can be optimised by a T‐shaped parasitic structure, which is beneficial to improving the bandwidth and aperture efficiency. A 180° ± 20° phase difference can be realised from 9.7 to 10.3 GHz only by controlling one PIN dipole loaded on the proposed element, which ensures stable radiation performance over a larger band. To validate the effectiveness of the proposed element, a prototype RRA containing 20 × 20 units is designed and measured. A ±60° beam scanning range with the gain drop of 3.2 and 3.3 dB in the xoz and yoz planes is realised, which verifies the wide‐angle beam‐scanning ability of the RRA. The measured peak gain is 25 dBi at 10 GHz in the broadside direction, corresponding to an aperture efficiency of 25.2%. Meanwhile, the 1‐dB gain bandwidth of the proposed RRA is 12.6%.

A folded reconfigurable reflectarray antenna for mono-pulse radar application is presented in this paper. The proposed antenna combines the properties of reconfigurable reflect-array antenna and folded reflectarray antenna. A reconfigurable reflectarray with $15\times 15$ elements is developed to verify the design method. The antenna design is calculated and simulated using MATLAB and HFSS, and detailed results are presented and discussed. The reconfigurable reflectarray antenna can operate at Ku-band and provide the performance of beam scanning. This reconfigurable reflectarray antenna has significant potential for satellite applications, due to its low profile, simple control and beam-scanning capability.

This work presents a pattern and polarization reconfigurable reflectarray antenna (RRA). Using 1-bit independently controlled dual-linearly polarized (DLP) units, the radiation beam of the RRA can be scanned with switchable polarization. The designed unit is composed of a crossed dipole, a metallic centered patch, four PIN diodes and biasing networks. By controlling the working states of the PIN diodes, the unit possesses independently 180° reflection phase shift in either of the two linear polarizations (LPs). A novel polarization manipulation method is introduced, and the 1-bit DLP unit can be transformed into a 2-bit unit with agile polarization. Based on the DLP unit, the proposed RRA can realize polarization reconfigurable among ±45° LPs, left-hand circular polarization (LHCP) and right-hand circular polarization (RHCP) by only changing the biasing voltages applied on the RRA. A prototype including 256 units is analyzed, fabricated, and measured. The 2-D beam-scanning ability is verified for dual-linear polarization and reconfigurable polarization. Good performance, including high gain and good polarization purity, can be observed. The proposed RRA features a wide beam scanning range and agile polarization, which makes it a good candidate for the wireless communication system.

In this letter, a 1-bit wide-angle and multi-polarization beam-scanning reconfigurable reflectarray antenna (RRA) is designed, fabricated and measured. The proposed RRA element consists of a square base, a circular turntable and three butterfly staircases with different heights based on 3D all-metal structure. The 1-bit reflected phase and orthogonal linear polarization reconfigurability can be achieved by rotating the proposed RRA element. Then, an all-metal RRA prototype with 26 × 26 rotational elements are fabricated, which is fed by a <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> -polarized corrugated horn with 20° inclination. The multi-polarization scanning beams are generated by dynamically rotating individual element on the aperture. The measured results show that the RRA prototype can achieve a 60° beam scanning with maximum scan loss of 3.3 dB in <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> -polarization, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</i> -polarization and circular polarization at 10.0 GHz. The peak gains of 27.2 dBi, 26.7 dBi and 27.1 dBi with aperture efficiency of 24.7%, 22.0% and 24.2% are obtained where the 1-dB gain bandwidth is 24.0%, 14% and 18% for <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> -polarization, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</i> -polarization and LHCP. The proposed RRA greatly reduces the cost, complexity and RF loss.

A liquid metal based 1-bit reconfigurable reflectarray antenna for beam-scanning applications

A <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$16\times 16$</tex> reconfigurable reflectarray antenna is designed, fabricated, and measured with low power consumption. The element is reconfigured by a FET transistor instead of a PIN diode. The beam scanning performance can be obtained by controlling the bias voltage on each element. The measured results demonstrate the beam scanning capability. The antenna operates at C band with a gain of 17.5dB and a scanning range of ±60° while the control power is only 0.74mW.

This paper presents a beam scanning electronically reconfigurable reflectarray configuration for Ku-band applications using a single varactor diode. A 15×15 center-fed reconfigurable reflectarray antenna is designed consisting of 225 octagonal shaped unit cells. The proposed tunable element has a unit cell size of 9.8 mm, developed on a 1.575 mm thick Taconic TLY-5 substrate. A single varactor diode is integrated with the tunable element to produce a reflection phase variation of 340° at 14.1 GHz. In this work, both the varactor and biasing circuit are placed beneath the substrate to avoid unexpected reflections, which leads to achieving a pencil beam of 8.1° beamwidth. The simulation results of the reconfigurable reflectarray antenna (RRA) shows good beam-scanning radiation performance of scanning range ±30° and a peak gain of 27.6 dBi. This structure provides a convenient solution for Ku-band distinctive applications like uplink operation in the direct broadcast satellite system, digital video broadcasting, earth exploration satellites, space research satellites, and defense systems.

Reconfigurable reflectarray antenna (RRA) has been considered a potential technology for future communication. However, few studies focus on investigating the intermodulation distortion induced by its active devices, which are employed to provide different compensation phases for the RRA elements. In this paper, the radiation pattern prediction for third‐order intermodulation (IM3) distortion of the RRA with embedded varactor diodes is first proposed. It is implemented with a nonlinear model of the varactor and full‐wave electromagnetism (FEM) simulation. The presented varactor model is first employed to design the RRA and then to acquire the power and phase of the IM3 signal in each element of the RRA, which is realized with a nonlinear harmonic‐balance and FEM co‐simulation. With the help of the HFSS software, the radiation pattern is achieved when the co‐simulation results of the RRA elements are input. The IM3 radiation measurement of the RRA is presented to verify the radiation pattern prediction of the IM3 signal. The consistent comparison results between the simulation and the measurement indicate that the proposed method is accurate. Significantly, the radiation pattern of the IM3 signal is different from that of the fundamental signal based on the designed RRA. It is meaningful and implies that it may have linearization approaches for the RRA. The proposed method will enhance the application of the RRA since the linearization approach is still a scientific challenge in future wireless networks.

An electronically steerable monopulse antenna based on reconfigurable reflectarray antenna (RRA) has been designed, fabricated and tested. The large-scale RRA at X-band is consisted of $160\times 64$ elements integrated with PIN diodes, and is controlled by arrays of 160 field-programmable gate arrays (FPGAs) in parallel, for the steerable monopulse patterns. The steerable sum-difference beams are achieved by the diode state distributions of the RRA. The gain of the RRA is measured to be 37.35dBi, and the null-depth is measured to be -43.51dB at the direction angle of 0 o. A null-depth of under -37.54dB is verified at the direction angle of 60°. The electronically steerable monopulse antenna based on RRA presents a low-cost solution for high resolution tracking applications.

In this article, a metal-only reconfigurable reflectarray antenna (RRA) is proposed for generation of diversified circular-polarization (CP) focused beams and mode-agile vortex beams in the X-band. The proposed RRA element has the 3-D metal-only configuration, which consists of three staircases with different heights, a turntable, a latch, and a base. By rotating the proposed RRA element in 45° steps, the ability of 1-bit phase quantization with orthogonal linear polarization (LP) reconfigurability can be realized. Then, a 26 × 26-elements reconfigurable reflectarray antenna feeding by a linear polarization horn antenna is designed to enable free conversion of line-to-circle polarization at the array level. Full-wave simulations show that the diversified circular-polarization beams can be synthesized by adjusting the aperture element distribution. Furthermore, a manually reconfigurable reflectarray antenna prototype is fabricated to obtain the actual performance of the synthetic LHCP focused beams. The measured maximum gain of the LHCP beams is 27.1 dBi, with the aperture efficiency of 24.2% where the beam point at 20°, and the 1-dB gain bandwidth is 18.0% (9.3 GHz − 11.1 GHz). Finally, mode-agile vortex beams can also be realized by using the proposed reconfigurable reflectarray antenna, and the simulated results show that the mode purity of vortex beams are all above 35% in different modes, and the maximum gain of the vortex beams is 21.1 dBi, with aperture efficiency of 6.1% where the mode of vortex beams is −1.

Design of a C-band reconfigurable reflectarray antenna (RRA) is presented. The RRA element consists of a fixed upper patch and a tunable slotted patch. By mechanically controlling the height of the slotted patch, the RRA element has a phase shift range of 324° with small element loss. A prototype with 408 elements is designed and fabricated. The measurements show that the gain of the 20° scanned beam is 25.7 dB and the aperture efficiency is 48.6%. The large-angle beam-scanning capability of the RRA is also verified within ±60° angular range, and well-defined scanned beams are obtained with maximum scan gain loss of 3.4 dB.

Design of a circularly polarized reconfigurable reflectarray antenna (RRA) at X band is presented. The RRA element employs concentric dual split rings, and can be mechanically rotated to obtain continuous 360° phase coverage with negligible element loss. A prototype with $15\times15$ manually rotated elements is first computed, simulated, and measured. Full-wave simulations show that the gain of the beam focused in ( $\theta =20^{\circ }$ , $\varphi = 0^{\circ }$ ) direction is 25.8 dB and the 1-dB gain bandwidth is over 28.6%. The measured results show that the beam at ( $\theta = 20^{\circ }$ , $\varphi = 0^{\circ }$ ) direction achieves the maximum gain of 25.6 dB, corresponding to an aperture efficiency of 51.8%. The beam-steering capability of the RRA is measured within ±60° angular range, and well-defined scanned beams are obtained with maximum scan loss of 3.7 dB. The versatile beam-forming capability of the RRA is also verified by synthesizing a square shaped beam and a cosecant shaped beam. Another micromotor-controlled prototype with 756 elements on an octagonal aperture is fabricated and its measured radiation performance validates the feasibility of the proposed design as well.

The design and simulation of a 1-bit broadband multi-polarization reconfigurable reflectarray antenna (RRA) in Ka band is proposed in this paper. The unit cell of the RRA consists of four patches and four p-i-n diodes, which can be used in broadband multi-polariztion working mode. By controlling the on-off state of the diodes, two kinds of phase shift states (0° and 180°) can be realized to form a 1-bit phase quantization. The reflection phase of unit cell should compensate for the spatial phase delay from the feed phase center. The simulated results show that the RRA can realized a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\pm 60^{\circ}$</tex> beam scanning in the frequency range of 31GHz-40GHz.

In this letter, a broadband and low loss circularly polarized (CP) electronically reconfigurable reflectarray antenna (RRA) that can operate over the X-band is reported. The proposed RRA invokes a new reconfigurable magneto-electric (ME) dipole based element for dynamically manipulating the phase of the back-scattered CP wave from each pixel, and hence, the direction of the reflected beam. The engineered wideband ME-dipole element and the design of a low loss reconfigurable perturbation structure contribute jointly to a superior CP bandwidth as well as a high efficiency. A reflectarray prototype with two-dimensional (2-D) beam scanning is designed, fabricated, and measured, demonstrating a wide-angle beam scanning capability. Besides, notable advances in bandwidth and aperture efficiency of the 1-bit CP RRA are identified, over the previous state of the art.