Steerable Antenna Array Research Articles

Optimizing Radar Functionality: Development of a Steerable Patch Antenna Array With Enhanced Bandwidth

AbstractToday, wireless communication systems need an antenna with a high gain, efficiency and beamsteering, as well as broadband capability, especially important in radar communications. The array antenna is commonly used in many applications due to its advantages, such as high gain and wide bandwidth. This paper presents an advanced design of a horizontally steerable planar antenna array intended for significant radar applications. A novel structure is used to create a compact array antenna of 8 × 3 elements. The design features a comprehensive 60° steering sector alongside a notable 12% bandwidth (4.45─5.42 GHz), using 8 × 3 planar array in an novel configuration. A three‐element series‐fed vertical array is utilized, employing aperture feeds with precisely sized patches to maximize performance. A detailed description of the design and refinement process of this array is presented, with emphasis on its exceptional capabilities for horizontal steering and bandwidth efficiency. By employing series‐fed vertical arrays with variable patch dimensions, we have successfully developed an antenna array that meets the stringent bandwidth requirements essential for radar technology, thereby enhancing the operational versatility of radar systems.

A compact SiGe D-band power amplifier for scalable photonic-enabled phased antenna arrays

To address the rising demand for high-speed wireless data links, communication systems operating at frequencies beyond {100},hbox {GHz} are being targeted. A key enabling technology in the development of these wireless systems is the phased antenna array. Yet, the design and implementation of such steerable antenna arrays at frequencies over {100},hbox {GHz} comes with a multitude of challenges. In particular, the cointegration of active electronics at each antenna element poses a major hurdle due to the inherent space constraints in the array. This article proposes a novel scalable concept for opto-electronic phased antenna arrays operating at 140 GHz. It details the system architecture of a transmitter that enables the implementation of large scale, wideband, 2D steerable phased antenna arrays and presents the design and measurement of a compact SiGe power amplifier (PA) chip to be used as one of its key building blocks. The amplifier achieves a gain of 20 dB at 135 GHz, features a P_{1dB} of 14.6 dBm and can support data rates up to 45 Gbps in a limited footprint of only 540μm × 550μm. This makes it one of the fastest, most powerful D-band power amplifiers in literature with a footprint compatible with frac{lambda }{2}-spaced phased array integration.

A Compact Dual-Beam Steering Antenna Array Based on a Simplified Beamforming Network

Dual-beam steering has the advantage of providing extensive and efficient scanning in multitarget environment. However, existing methods of dual-beam steering antenna arrays are generally large or complex in structure. Therefore, this paper proposes a simplified beamforming network based on the theoretical analysis on a Hadamard matrix. The proposed beamforming network was constructed using a simplified topology, consisting of three 0°/180° couplers and four PIN diodes. For verification, a dual-beam steering antenna array at 2.4 GHz was designed, fabricated, and measured. Both simulated and measured results agree well with each other. The size of the fabricated network is 0.70 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</sub> × 0.93 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</sub> , which is only 20.3% of the size occupied by a traditional Hadamard matrix. At the center frequency, the implemented antenna array realizes steering angles of 0°, ±19°, ±31°, and ±51°, demonstrating good dual-beam steering properties.

A Dual-Band Beam-Steering Array Antenna With Integration of Reflectarray and Phased Array

This letter presents a dual-frequency beam steering array antenna (DBSA), which integrated a height adjustable reconfigurable reflectarray of C-band and a phased array of X-band. Each antenna element can achieve an arbitrary phase shift value in the range of 0° to 360° by controlling the height-adjustable device and digital phase shifter at 5.8 GHz and 10 GHz, respectively. Accordingly, the DBSA can be fed by two sets of feed networks independently, which can simultaneously achieve beam steering of arbitrary angle at dual frequencies. A prototype of 8 × 8 DBSA was designed and fabricated to realized beam scanning in the angle range from -40° to 40° in the XOZ plane at 5.8/10 GHz respectively. The measured maximum gain of DBSA is 14.4/21 dBi with aperture efficiency of 32.9% / 50.6% at 5.8/10 GHz respectively. The proposed DBSA can be applied in satellite communication to realize air-to-ground and inter-satellite communications at the same time.

Mechanical Beam Steering Array Antenna With Tunable Height

This letter presents a mechanical beam steering array antenna (MBSA) with tunable height elements. Each antenna element is composed of a U-slot radiation patch and a stepper motor supported by the three-dimensional-printed structure. By controlling the height of each antenna element using a stepper motor, an arbitrary phase shift value in the range of 0°∼360° can be achieved. In addition, steering high-gain beams can be generated by flexibly adjusting the height of each antenna element. A prototype of 8 × 8 MBSA was designed and fabricated to realize beam scanning in the pitch angle range from −40° to 40° in the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">xoz-</i> plane and near-field focusing. The measured gain of MBSA is 23.3 dBi with an aperture efficiency of 85.7% at 10 GHz. The proposed MBSA has the advantages of simple structure, low cost and high stability, which can be applied in satellite communication systems.

Design and implementation of a beam-steering antenna array using butler matrix feed network for X-band applications

This article proposes the design, simulation, fabrication and testing of a beam steerable antenna array using a 4 × 4 Butler Matrix feed network technique. The proposed antenna is developed to operate at the X band frequency range. The integrated antenna array and the Butler Matrix feed network operating at 10 GHz has a bandwidth of approximately 2 GHz with an achieved gain of 12 dBi. The main beam pattern of the antenna array is switched between four directions (+10°, −38°, +38°, −10°) providing an effective coverage of over 100°. The proposed antenna has the advantages of low cost, easy fabrication, and simplicity.

High Gain Beam Steering Antenna Arrays with Low Scan Loss for mmWave Applications

In millimeter-wave (mmWave) communications, the antenna gain is a crucial parameter to overcome path loss and atmospheric attenuation. This work presents the design of two cylindrical conformal antenna arrays, made of modified rectangular microstrip patch antenna as a radiating element, working at 28 GHz for mmWave applications providing high gain and beam steering capability. The microstrip patch antenna element uses Rogers RO4232 substrate with a thickness of 0.5 mm and surface area of 5.8 mm × 5.8 mm. The individual antenna element provides a gain of 6.9 dBi with return loss bandwidth of 5.12 GHz. The first antenna array, made by using five conformal antenna elements, achieves a uniform gain of approximately 12 dBi with minimal scan loss for extensive scan angles. In the second antenna array, a dielectric superstrate using Rogers TMM (10i) was used to modify the first antenna array. It enhanced the gain to approximately 16 dBi while still maintaining low scan loss for wide angles. The proposed array design method is very robust and can be applied to any conformal surface. The mathematical equations are also provided to derive the array design, and both array designs are verified by using full-wave simulations.

A Narrow Beam Steering Antenna Array for Indoor Positioning Systems Based on Wireless Sensor Network

This paper proposes the 2.45 <i>GHz</i> planar Beam Steering Antenna Array for Indoor Positioning Systems. The antenna array consists of a phase shifter based on a 4 &#x00D7; 4 Butler matrix, and an array of four dipole Yagi antennas. By choosing one of four beams using a switching controller, the main beam of the antenna can steer in four directions from +37&#x00B0;, &#x2013;12&#x00B0;, +12&#x00B0; to &#x2013;36&#x00B0;. The antenna has a narrow fan beam with a beamwidth in the azimuth plane of from +21.5&#x00B0; to +24.5&#x00B0; and in the elevation plane of approximately 90&#x00B0; which effectively minimizes multipath signals. These advantages are suitable for positioning systems to increase location accuracy. The antenna achieves a peak gain of from 9.1 to 9.8 <i>dBi</i> in four directions, a wide band of 400 <i>MHz</i>. The fully electronically steerable antenna prototype has been designed using CST software, simulated based on the finite element method, and fabricated on the RO4003C substrate as well as measured. The antenna is implemented in the Indoor Positioning System using three different location methods, including trilateration, triangulation, and fingerprinting, to highlight the antenna&#x2019;s advantages in improving location accuracy with the ratio between the mean location error and area of 0.051, 0.033, and 0.023 respectively.

Circularly polarized beam steering array antenna fed by low magnitude and phase error response of Butler matrix to use pattern stabilization applications

In this work, a novel circularly polarized (CP) Fabry–Perot resonator beam-steering antenna array with capability covering C-band applications is introduced. The proposed antenna array caters to a relatively constant high gain at a broadband impedance bandwidth in comparison with conventional arrays. The presented antenna is designed based on a broadband Butler matrix feeding network which is able to stabilize direction patterns at different frequencies for each of the ports for the sake of phase distribution in whole operation frequency with low phase error.

A novel approach for design of beam steerable aperiodic planar array antenna with reduced number of elements

This paper introduces the design of an aperiodic beam steerable planar array antenna using a novel strip-projection (SP) method, offering the reduced array elements with improved peak SLL with beam scan. The SP method generates the aperiodic lattice by projecting a section of the 3D body-centric tetragonal lattice onto the aperture and rotating it using Rodrigue's formula. The optimized lattice parameters are obtained using Jaya algorithm. The proposed SP method requires only three optimization parameters for any aperture dimensions and 21.9% less elements as compared to the rectangular lattice. For comparison, pinwheel-based aperiodic planar array antenna has been designed and analyzed. The peak SLL is maintained <−11.63 dB and <−12.70 dB for 0°-30° beam scan by proposed array and pinwheel-based array respectively. Both types of aperiodic lattice have been populated with S-band dielectric resonator antenna and simulated. Position standard deviation has also been introduced and computed to quantify the aperiodic distribution.

A Low-Complexity Reconfigurable Multi-Antenna Technique for Non-Terrestrial Networks

Multi-Antenna communication techniques are an efficient and relatively simple approach for the performance improvement of wireless communication systems. However, the direct application of multi-antenna techniques to an aerial communication system is not always feasible due to the constraints induced by the aerial platforms. Reconfigurable intelligent antenna technologies could provide an efficient solution to these problems and thus they are considered as ideal candidates for adaption in the aerial communication platforms that will be used in the 5G and beyond communication networks. In this paper, a joint Tx-Rx beamforming with beam selection and combining technique is proposed for improving the performance of an aerial communication system supported by electronically steerable antenna arrays. The main idea of the proposed scheme is to select, using an SNR maximization criterion, a pair of beam patterns between each RF chain of the ground station and the aerial platform, and combine the received SNRs under the maximal ratio principle. Initially, an analytical stochastic framework has been developed that is based on a Markov chain model, which is used to investigate the statistics of the received SNR. Then, an implementation of the novel beamforming and pattern adaptation scheme is presented, with the use of Electronically Steerable Parasitic Array Radiators (ESPAR), properly designed for Ground Station to UAV links. In addition, a realistic simulator is also developed with proper channel model selection, by the aid of which, the performance of the proposed scheme has been evaluated in conjunction with the extracted analytical results.

Time‐modulated multibeam steered antenna array synthesis with optimally designed switching sequence

SummarySteering the radiation pattern of an antenna array towards the desired spatial angle is beneficial for modern‐age communication systems. The generation of multiple steered patterns by enhancing the first‐order harmonics of a time‐modulated antenna array (TMAA) with controlled radiation features is proposed in this paper. Suitable switching sequences are designed to realize an efficient electronic beam steering with these simultaneously generated narrow directional beam patterns. TMAAs are considered the time‐domain counterparts of phased arrays where high‐speed switches are used to achieve a weighted response by periodically modulating the array elements instead of attenuators or phase shifters. This periodic modulation inherently produces spurious harmonic patterns generally considered as power loss in unintended directions. The beam steering aimed in this paper is accomplished by exploiting the first‐order harmonic patterns in some specific directions keeping the fundamental pattern unaltered. The intended first positive and first negative harmonic components of the TMAA are utilized as steered multibeam patterns, whereas all the remaining harmonic components are suppressed to improve the efficiency of the array. To achieve this, suitable switching sequences are designed by optimizing the ON‐time duration and switching intervals of the elements with a wavelet mutation‐based particle swarm optimization (PSOWM). 16‐element linear TMAA is used to generate the desired patterns with low sidelobe levels (SLLs) for enhanced performance. Numerical results obtained for spatially independent steered patterns are presented and compared with the state‐of‐the‐art literature results.

Surface-Mounted Ka-Band Vivaldi Antenna Array

The first electrically steerable dual-polarized Ka-band Vivaldi antenna array with connector-less, surface-mount interface is developed. The antenna interface includes integrated coaxial feed lines within the antenna element structure and contact pads on the PCB. The antenna array covers the frequency range from 26 to 40 GHz with a beam steering range of approximately ±60° in the elementary planes and ±50° in the diagonal plane, having less than 3 dB of scan loss. The 8×8 antenna array is manufactured with a feeding network for one polarization, and the operation of the interface and the electrical beam steering is demonstrated. Measurements are used to characterize the manufactured feed network, the gain of the antenna array and the steering range. The measured gain is between 19 and 22 dB, agreeing very well with the simulation and implying that the antenna interface operates properly. Furthermore, the antenna scan measurements agree with the simulation results.

Flat-Panel Mechanical Beam Steerable Array Antennas With In-Plane Rotations: Theory, Design and Low-Cost Implementation

We present a compact, flat-panel phased-array antenna design that beam steers using only mechanical in-plane rotations. We explain the steering mechanism and characterize the beam analytically and numerically. Measurements of two prototype antennas for different frequencies validate the concept and modeling. The prototype designs are described in detail and feature added phase-offset control of the array elements in the aperture layout. Potential applications include low-cost and low-power flat-panel user terminals for the next generation of aerial and space communication systems.

Design of a beam steering antenna array using 8x8 butter matrix for indoor positioning system

ABSTRACT This paper proposes a 5 GHz beam steering antenna array (BSAA) based on 8 × 8 Butler Matrix for Indoor Positioning System (IPS). The main beam of BSAA is narrow in azimuth plane with 12° of beam-width while the beam-width in elevation plane is 50°-120°. The steering angle of BSAA in azimuth plane is 108° with eight beams at −52°, −37°, −20°, −8°, +9°, +25°, +40°, +56°, and the peak gains of 7.8 dBi – 11 dBi. The wide beam-width in elevation plane helps to increase the positioning area of BSAA. Also, the narrow beam-width in azimuth plane allows improving the accuracy of IPS.

Efficient Beam Sweeping Algorithms and Initial Access Protocols for Millimeter-Wave Networks

5G millimeter-wave (mmW) systems rely on electronically steerable antenna arrays to support directional communications. Directionality complicates the initial access (IA) process, whereby a base station (BS) announces itself to nearby user equipments (UEs), giving them the opportunity to associate with this BS. Existing approaches for IA suffer from long discovery time and/or nonnegligable probability of missing UEs. In this paper, we propose FastLink, an efficient IA protocol for mmW systems, in which discovery beacons are transmitted/received using the narrowest possible beams, allowing for high beamforming gains and low misdetection rate, while maintaining low discovery time. Fastlink executes a unique algorithm, called 3-dimensional peak finding (3DPF), to find the best beam in logarithmic time. We formulate the beam-finding process as a sparse problem and use compressive sensing to determine the minimum number of measurements needed for this process. We first study FastLink for the discovery of a single UE and then extend our analysis to a multi-user scenario. Both simulations and over-the-air experiments based on a custom mmW testbed are used to evaluate FastLink. Our results verify its efficiency, and show that it can reduce the search time by 90% compared to the scanning approach used in 802.11ad systems.

Beam Steerable and Frequency Reconfigurable Antenna Array for 5G Mobile Networks

Beam Steerable and Frequency Reconfigurable Antenna Array for 5G Mobile Networks

Low-Profile Beam Steerable Patch Array With SIW Feeding Network

This paper presents a novel beam steerable array antenna that encompasses fully planar, low profile and lightweight characteristics for satellite communication (SatCom) applications. The proposed array contains a wideband linear source generator (LSG), an array of circular patches, and an inductive surface. The LSG is designed based on the substrate-integrated-waveguide (SIW) technology, whereas the patches are regarded as coupling circular scatterers, placed on the inductive surface for converting surface wave into the radiating wave. Each scatterer acts as a location-dependent phaser that can tailor the farfield behaviour to leverage beam steering, and is achieved by changing its distribution mechanically. A prototype of the proposed design has been fabricated and measured to evaluate the antenna performance. The measured results are in good agreement with the simulated results. The array antenna operates well with S 11 <; -10 dB in the frequency band of 10.75-12.5 GHz and has stable radiation performance with beam steering capability of nearly ±60° in the elevation plane. The total height of the proposed array is about 5.1 mm (0.19λ 0 ). It is envisaged that the proposed antenna array will empower small moving platforms due to low cost, low profile and suitability for mass production.

Outage of Millimeter Wave Links With Randomly Located Obstructions

According to current regulation, millimeter wave links can only rely on low transmission power, which calls for high gain steerable antenna arrays to generate very directional beams bringing signals of detectable power to the intended receiver. However, beam directionality, jointly with the very limited scattering and diffracting capabilities of millimeter waves, implies high sensitivity to obstructions, which can cause link outage. This article proposes new analytical models for the estimation of the outage probability of millimeter wave indoor and outdoor links, based on the derivation of the distribution of the obstruction length along the beam. To derive the models, we use stochastic geometry and assume randomly located obstructions. The proposed models are used to explore the impact on millimeter wave link performance of a number of parameters such as distance between transmitter and receiver, obstruction shape and size, density of obstructions, carrier frequency and modulated bandwidth. The models can be used to study realistic 2D and 3D scenarios, and are shown to be quite accurate by comparing analytical predictions and simulation results in numerous cases.

ASIP development of a real-time control module for a retrodirective antenna array

Electronically steerable antenna arrays become attractive due the possibility of simultaneously steering the main lobe in the desired direction and suppressing side lobes only by means of electronic control of excitation currents, hence avoiding mechanical components. However, this type of antenna requires intensive calculation for setting the excitation current of each array element in order to shape the radiation pattern for retransmission, thus demanding a dedicated hardware. This work reports the development of a digital control module for a retrodirective antenna array based on a customized dedicated microcontroller called PAMPIUM, which has been implemented on FPGA, aiming real-time response and low power consumption. A methodology for generation of optimized hardware in terms of area, power efficiency and performance is discussed. A design tool to provide the user with a practical and intuitive environment has been developed, which allows simulating and assessing statistics about execution and performance of the designed architecture. The developed digital control module is capable of updating the current coefficients of an eight-element antenna array in less than 1 s with a power consumption of 5.3 mW for beamsteering angles from 0° to 60°. The proposed methodology allows the demonstration of full efficiency of a retrodirective antenna array system.