Antenna For Wireless Communications Research Articles

Vehicular Bidirectional Internal Antenna with Asymmetric Gain Characteristics to Compensate for Backward Link Path Loss due to Interior Obstacles

Wireless communication technologies are expected to become essential in future self-driving vehicles. This study presents an antenna for vehicle wireless communication with a bandwidth of 75 MHz at a Wireless Access in Vehicular Environment frequency of 5.885 GHz. To compensate for the backward link path loss from the vehicle interior and passengers, the antenna is designed to have asymmetric gains of 0 and 6 dBi at 0° and 180°, respectively. The antenna is validated through an outdoor road test. We measured the received continuous-wave (CW) power, received signal strength indicator, and packet-delivered ratio (PDR) of the digital signal under vehicle-to-vehicle communication mode. Similar power is received in both the backward and forward scenarios. The forward and backward PDR are also similar.

A Novel Approach of Design and Analysis of a Hexagonal Fractal Antenna Array (HFAA) for Next-Generation Wireless Communication

The study and exploration of massive multiple-input multiple-output (MMIMO) and millimeter-wave wireless access technology has been spurred by a shortage of bandwidth in the wireless communication sector. Massive MIMO, which combines antennas at the transmitter and receiver, is a key enabler technology for next-generation networks to enable exceptional spectrum and energy efficiency with simple processing techniques. For massive MIMOs, the lower band microwave or millimeter-wave band and the antenna are impeccably combined with RF transceivers. As a result, the 5G wireless communication antenna differs from traditional antennas in many ways. A new concept of the MIMO tri-band hexagonal antenna array is being introduced for next-generation cellular networks. With a total scaling dimension of 150 × 75 mm2, the structure consists of multiple hexagonal fractal antenna components at different corners of the patch. The radiating patch resonates at 2.55–2.75, 3.45–3.7, and 5.65–6.05 GHz (FR1 band) for better return loss (S11) of more than 15 dB in all three operating bands. The coplanar waveguide (CPW) feeding technique and defective ground structure in the ground plane have been employed for effective impedance matching. The deviation of the main lobe of the radiation pattern is achieved using a two-element microstrip Taylor antenna array with series feeding, which also boosts the antenna array’s bandwidth and minimizes sidelobe. The proposed antenna is designed, simulated, and tested in far-field radiating conditions and generates tri-band S-parameters with sufficient separation and high-quality double-polarized radiation. The fabrication and testing of MIMO antennas were completed, where the measurement results matched the simulation results. In addition, the 5G smartphone antenna system requires a new, lightweight phased microwave antenna (μ-wave) with wide bandwidth and a fire extender. Because of its decent performance and compact architectures, the proposed smartphone antenna array architecture is a better entrant for upcoming 5G cellular implementations.

A Review on Reconfigurable Antennas for 4G and 5G Wireless Communications

A Review on Reconfigurable Antennas for 4G and 5G Wireless Communications

Interdigitated photoconductive terahertz antenna for future wireless communications

AbstractRecently, the technology buzz on utilization of terahertz (THz) technology in beyond 5G and 6G communication is growing due to the demands for large network capacity, bandwidth, and ultrahigh data rates. The THz frequencies are prudent for short‐range future wireless communication systems as they provide extraordinary channel capacity with data rates from few Gb/s to Tb/s due to its ultra‐wide spectrum bandwidth. However, there exists many challenges in designing devices that operate under THz frequencies. The photo‐conductive antenna (PCA) is one of the crucial components that support realization of ultrafast wireless THz communications. In this paper, investigations on photoconductive antennas with interdigitated electrodes (IDEs) have been presented for THz communications with an equivalent circuit model for IPCA with corresponding solved expressions. The results show that the maximum THz field strength of 4.41 × 105 V/m is achievable by a 10 μm interdigitated teeth length IPCA with larger spectrum bandwidth of about ~8 THz. The antenna module makes the possibility of miniaturization of the THz sources and detectors for the emerging variety of wireless THz applications.

Improving Sensor Network Performance with Directional Antennas: A Cross-layer Optimization

The use of directional antennas for wireless communications brings several benefits, such as increased communication range and reduced interference. One example of directional antennas are electronically switched directional (ESD) antennas that can easily be integrated into Wireless Sensor Networks (WSNs) due to their small size and low cost. However, current literature questions the benefits of using ESD antennas in WSNs due to the increased likelihood of hidden terminals and increased power consumption. This is mainly because earlier studies have used directionality for transmissions but not for reception. In this article, we introduce novel cross-layer optimizations to fully utilize the benefits of using directional antennas. We modify the Medium Access Control (MAC) , routing, and neighbor discovery mechanisms to support directional communication. We focus on convergecast investigating a large number of different network topologies. Our experimental results, both in simulation and with real nodes, show when the traffic is dense, networks with directional antennas can significantly outperform networks with omnidirectional ones in terms of packet delivery rate, energy consumption, and energy per received packet.

Versatile metasurface platform for electromagnetic wave tailoring

The emergence of metasurfaces provides a novel strategy to tailor the electromagnetic response of electromagnetic waves in a controlled manner by judicious design of the constitutive meta-atom. However, passive metasurfaces tend to perform a specific or limited number of functionalities and suffer from narrow-frequency-band operation. Reported reconfigurable metasurfaces can generally be controlled only in a 1D configuration or use p-i-n diodes to show binary phase states. Here, a 2D reconfigurable reflective metasurface with individually addressable meta-atoms enabling a continuous phase control is proposed in the microwave regime. The response of the meta-atom is flexibly controlled by changing the bias voltage applied to the embedded varactor diode through an elaborated power supply system. By assigning appropriate phase profiles to the metasurface through voltage modulation, complex beam generation, including Bessel beams, vortex beams, and Airy beams, is fulfilled to demonstrate the accurate phase-control capability of the reconfigurable metasurface. Both simulations and measurements are performed as a proof of concept and show good agreement. The proposed design paves the way toward the achievement of real-time and programmable multifunctional meta-devices, with enormous potential for microwave applications such as wireless communication, electromagnetic imaging, and smart antennas.

Improvement of wider bandwidth using dual e–shaped antenna for wireless communications in 5G applications

Improvement of wider bandwidth using dual e–shaped antenna for wireless communications in 5G applications

A Study on Different Slot Position for Designing Dual Band Microstrip Antenna for 5G Wireless Communication

In this paper, four antenna designs with different slot positions for dual band frequencies are analysed. A reference antenna operating at 8 GHz is used at a dimension of 30 mm2 using Rogers RT58880 as the substrate with a dielectric constant of 2.2. Two slots are etched in order to produce a dual band. The antenna resonates at 8 GHz and 15 GHz. Return loss at 8 GHz and 15 GHz are −17.03 dB and −21.37 dB with gain at 7.39 dB at 8 GHz. By using CST Microwave Software, the simulated results are obtained. The slotted antenna produces a dual band antenna that is a suitable candidate for 5G wireless communication tool.

Microstrip patch antenna with metamaterial using superstrate technique for wireless communication

This work builds a metamaterial (MTM) superstrate loaded on a patch of microstrip antenna for wireless communications. The MTM superstrate is made up of four G-shaped resonators on FR-4 substrate with a relative permittivity of 4.4 and has a total area of (8×16) mm2, and is higher than the patch. The MTM superstrate increases antenna gain while also raising the input reflection coefficient. When it is 9 mm above the patch, the gain increased from 3.28 dB to 6.02 dB, and when it is 7 mm above the patch, the input reflection coefficient was enhanced from -31.217 dB to -45.8 dB. When the MTM superstrate loaded antenna was compared to the traditional unloaded antenna, it was discovered that metamaterials have a lot of potential for improving antenna performance.

무선통신 주파수 대역에서 운용할 수 있는 CPW 급전 초광대역 In-Building 중계기 안테나 설계

In this study, a super-wideband (SWB) in-building repeater antenna for mobile communication bands (0.8~0.9 GHz, 1.7~1.8 GHz, 1.9~2.1 GHz, 2.5~2.6 GHz, 3.4~3.7 GHz, 26.5~28.9 GHz), WLAN bands (2.4 GHz, 5.1~5.8 GHz), and ISM bands(2.4~2.5 GHz, 5.7~5.8 GHz) is proposed. The antenna is implemented in CPW feeding, a polygonal radiation patch, and slots on an FR4 substrate (dielectric constant= 4.4, thickness= 1.6 mm). The operating frequencies of the fabricated antenna are 0.83~15.6 GHz and 24.6~30.0 GHz, which meet a 10 dB return loss. In particular, the 0.83~15.6 GHz band has a bandwidth ratio of 18.8:1, which meets the minimum SWB bandwidth ratio of 10:1. The antenna gains at the frequencies of interest are 3.2 dBi (1.0 GHz), 4.5 dBi(3.5 GHz), and 8.2 dBi(26.5 GHz). Considering the radiation patterns, the proposed antenna will perform optimally as a repeater antenna when installed perpendicular to the ceiling facing the floor, thereby replacing the numerous wireless communication antennas installed inside buildings.

Analysis of single and multiple on-chip antenna for intra-chip wireless communication with four antenna transceiver model

Analysis of single and multiple on-chip antenna for intra-chip wireless communication with four antenna transceiver model

A Cross-Joint Vivaldi Antenna Pair for Dual-Pol and Broadband Testing Capabilities

The non-standalone 5G antenna wireless communication standard and devices operating under Wi-Fi 5, 6, and 6E operate at the 3 GHz frequency bands and above. With the increasing demand for these devices and technologies, it is crucial to test them rapidly and economically for commercial usage. This paper presents a dual-polarized Vivaldi antenna for the over-the-air (OTA) measurement of wireless communication devices used in the 3–7 GHz band. The dual-polarization performance is realized by vertically intersecting two planar Vivaldi antennas and soldering them at the back end. A three-step 1/4 wavelength balun is applied to the input for the wideband impedance matching of the antenna, which is attached to a Teflon holder for easy mounting. It has excellent performance and is designed to be manufactured at low cost. The fabricated antenna was tested in an anechoic chamber and showed S11 less than -10 dB from 2.63–7.15 GH, and a realized gain of more than 5 dBi from 3 GHz and above. A measured half-power beam width of more than 60° was realized with symmetric E/H-plane. Much of the required symmetry was achieved with the designed Teflon holder. The antenna has a measured cross-polarization discrimination of better than 15 dB across the entire operating bandwidth.

Design of High Gain Wearable Antenna Based on Wireless Body Area Network Communications

This paper presents a wearable antenna for Wireless Body Area Network communication. A 3×3 array artificial magnetic conductor structure (AMC) is loaded at the bottom of the antenna to reduce the backward radiation and improve the antenna gain. The simulated results show that the antenna can completely meet the working requirements in the bent state. After the addition of AMC array, the maximum gain reaches 7.53 dB, and the SAR value of human tissue can be reduced by about 94%. In addition, we have also processed and tested the antenna. The measured results are in good agreement with the simulated results, and its working bandwidth includes the low-frequency band of the ISM frequency band for WBAN communication, which can meet the working requirements of the antenna.

Backlobe Radiations Reduction with Patch Antenna Using Multilayered Dielectric Structure

Backlobe radiations are the key stumbling block to using microstrip patch antennas in wireless communication, but they can be minimised by using a slot-coupled feeding technique. This paper proposes a microstrip patch antenna with a multilayer structure. The Ansoft High Frequency Structure Simulation is used to describe and model this slot-fed antenna, which has an improved gain of 5.6dB and directivity of 5.9dB and resonates at a frequency of 2.25GHz.

High-Performance Implementation of Wideband Coherent Signal-Subspace (CSS)-Based DOA Algorithm on FPGA

Coherent Signal-Subspace (CSS) is a technique to separate the wide frequency band into narrowband components which can be applied in many applications such as smart antennas for wireless communications and radar. However, CSS is computationally intensive and may not achieve the real-time requirement. Therefore, this work aims to propose an efficient implementation of the CSS method on Field-Programmable Gate Array (FPGA) to achieve the desired performance. Different parallelization and optimization techniques such as loop unrolling, loop pipelining, dataflow, and loop flattening are adopted and applied to explore the opportunities of any computation and storage that could be eliminated in order to achieve high efficiency. The results of the proposed optimized implementation achieve the highest performance compared with other related implementations.

Performance analysis of patch antenna for underwater wireless communication in seawater

<span lang="EN-US">Underwater wireless communication in seawater is becoming more interesting and challenging in recent years. The development of antenna for underwater wireless communication in seawater at 900 MHz UHF range frequency is implemented by using patch antenna. In this paper, the antennas were designed using FEKO, an electromagnetic simulation software, and a suitable size for rectangular patch antenna for seawater application was developed to study the relevance between λ0 with W and L in seawater. The difference between the patches in free space and seawater was the L size, which was slightly bigger, about 0.9 mm, than free space size. But the gain for patch antenna in seawater was found at -2.51 dBi, lower than patch antenna in free space, which was 5.76 dBi due to the path loss in seawater. This shows that attenuation happened, and a better antenna will be design. The one that has better gain, which is around above 2 dBi in seawater, in order to get better performance antenna in seawater environment.</span>

Novel Design of Penta Band Planar Inverted F Antenna for Wireless Communication

In this paper, a novel penta-band internal single feed low profile Planar Inverted F Antenna (PIFA) that operates in several bands including Global System for Mobile Communication GSM 900 MHz, GSM 1800 MHz, Global Positioning System (GPS), Universal Mobile Telecommunications Service UMTS 2100 MHz, 1800 MHz, Advanced Wireless Services AWS 1700 MHz and Industrial, Scientific and Medical Band ISM 2.4 GHz has been proposed. The proposed antenna has a rectangular and slotted radiating patch suspended above a rectangular ground plane, which is also slotted. A 0.6 mm thick FR4 dielectric substrate of the same size as the rectangular ground plane has been used between the radiating patch and the ground plane. By optimizing the slots on the radiating patch as well as the ones on the ground plane, it has been noticed that the antenna can work at five distinct bands of frequencies with good operating bandwidth. The slots on the ground plane have contributed further to generate multiband frequencies with improved bandwidth and to form almost omnidirectional radiation patterns at the resonating frequencies. The simulation and the analysis of the proposed antenna have been done using Computer Simulation Technology (CST) Studio Suite software. This novel compact penta band PIFA antenna shows very good performance at all the frequencies of operations and it will be a suitable candidate for wireless communications.

1‐D reconfigurable graphene‐strips leaky‐wave antenna with different feeders for wide scanning angles

This paper introduces electronic-beam switching graphene-strips leaky-wave antenna (GS-LWA) for THz wireless communications with different feeding structures. The antenna is constructed from graphene-strips printed on silicon oxide substrate with total dimensions of 1350 × 300 × 35 μm3. The graphene tunable conductivity is used to control the GSLWA radiated beam direction without changing its physical structure. A scanning range of 94° (from −68° to 26°) is achieved at 2 THz using different codes. The effect of different plane wave launchers on the radiation characteristics of GS-LWA is investigated. A planar substrate integrated waveguide horn antenna as a plane wave launcher is designed. It introduces a peak gain of 18.2 dBi with a bandwidth of 21.95% and SLL of 10.6 dB. End-fire radiation from parabolic reflector is employed to launch plane-wave in the GS-LWA. A matching BW of 0.82 THz is achieved with peak gain of 18 dBi. A coplanar fed Yagi-Uda like structure element is studied using a single element and two elements array. The two elements array provided the highest matching of −40 dB over BW of 6% and gain of 16.5 dBi. Finally, tapered microstrip line is investigated. It introduced the lowest SLL −16.1 dB with a gain of 17.5 dBi and BW of 39.57% (from 1.5 to 2.24 THz). The selection of proper feeding structure depends on the required matching BW, peak radiated gain, and the lowest SLL. Full-wave analysis of the GS-LWA launched by different feeding methods is introduced.

A 300-GHz low-cost high-gain fully metallic Fabry\u2013Perot cavity antenna for 6G terahertz wireless communications

A low-cost, compact, and high gain Fabry–Perot cavity (FPC) antenna which operates at 300 GHz is presented. The antenna is fabricated using laser-cutting brass technology. The proposed antenna consists of seven metallic layers; a ground layer, an integrated stepped horn element (three-layers), a coupling layer, a cavity layer, and an aperture-frequency selective surface (FSS) layer. The proposed aperture-FSS function acts as a partially reflective surface, contributing to a directive beam radiation. For verification, the proposed sub-terahertz (THz) FPC antenna prototype was developed, fabricated, and measured. The proposed antenna has a measured reflection coefficient below − 10 dB from 282 to 304 GHz with a bandwidth of 22 GHz. The maximum measured gain observed is 17.7 dBi at 289 GHz, and the gain is higher than 14.4 dBi from 285 to 310 GHz. The measured radiation pattern shows a highly directive pattern with a cross-polarization level below − 25 dB over the whole band in all cut planes, which confirms with the simulation results. The proposed antenna has a compact size, low fabrication cost, high gain, and wide operating bandwidth. The total height of the antenna is 1.24 {lambda }_{0} ({lambda }_{0} at the design frequency, 300 GHz) , with a size of 2.6 mm × 2.6 mm. The proposed sub-THz waveguide-fed FPC antenna is suitable for 6G wireless communication systems.

A Comparative Study of UWB Micro-strip Antenna for Wireless Communication and RF Energy Harvesting

Ultra Wide Band (UWB) is first-class famous technology in recent wireless communication since it affords excessive data rates and excellent high-quality offerings. FCC (Federal Communications Commission) opens a 7.5 GHz spectrum (extending 3.1 GHz - 10.6 GHz) in 2002 for wireless ultra-wide band system [1]. With high data rates of wireless communication technology, UWB is increasingly advancing and the micro-strip antenna is also being developed with bandwidths of 1 to 5%. However, within the ultimate decade, UWB has additionally been proposed as a RF energy harvester. The strategies which enhance bandwidth are one of the popular research areas in patch antenna’s field. The bandwidth is generally described as just a percent of the width of the desired frequency range and the resonant antenna frequencies. Other constraint like return loss, efficient radiation and VSWR (voltage standing wave ratio) are also accustomed to describe the bandwidth of a micro-strip antenna. Several things need to be considered into account in choosing an ideal aerial for Ultra-Wide Band including physical structure, performance and frequency band, and radiation quality and emission pattern.The major issue in UWB antenna system is to achieve only the wide bandwidth with high levels of radiation efficiency and compact size. So several method have been extensively investigated for the wide bandwidth of patch antenna and to optimize the qualities of array antenna, as described in various published articles in this survey paper.