Dielectric Resonator Antennas: Applications and developments in multiple-input, multiple-output technology

This article presents a comprehensive review of multiple-input, multiple-output (MIMO) dielectric resonator antennas (DRAs) that have evolved in the past decade. In addition to the major challenges faced during designing an MIMO DRA, this article also discusses research gaps that must be filled in the future. Exploring the advantages of DRAs, numerous novel designs have been proposed in the last few years

A dual band hybrid mimo dielectric resonator antenna for long term evolution applications

Dielectric resonator antennas (DRAs) are widely used in the last two decades. Comparison with microstrip patch antenna, DRA can provide high bandwidth, low metallic losses and high radiation efficiency. Smaller size of meander line is suggested to replace conventional microstrip line. Multiple-input multiple-output (MIMO) can increase more channel capacity and throughput compared to single port. In this project, a dual band MIMO hybrid DRA for LTE applications is proposed. This hybrid technique will be consisted of DRA and meander-typed antenna as radiators which can operate at LTE band 8 (880-960 MHz) at ???? = 900 MHz, LTE band 2 (1.85-1.99 GHz), 3 (1.71-1.88 GHz), and 9 (1.7499-1.7849 GHz) at ???? = 1.8 GHz respectively. A triple band is obtained in the simulations of HFSS software with additional 2.3 GHz for LTE Band 30 (2.305-2.360 GHz). The MIMO prototype has bandwidth up to 6.53 % at Port 1 and 12.68 % at Port 2, with isolation ranging - 6.10 dB to - 22.76 dB at 0.9, 1.5, 1.8 and 2.5 GHz

Antenna Design for 5G and Beyond

With the rapid evolution of the wireless communications, fifth-generation (5G) communication has received much attention from both academia and industry, with many reported efforts and research outputs and significant improvements in different aspects, such as data rate speed and resolution, mobility, latency, etc. In some countries, the commercialization of 5G communication has already started as well as initial research of beyond technologies such as 6G.MIMO technology with multiple antennas is a promising technology to obtain the requirements of 5G/6G communications. It can significantly enhance the system capacity and resist multipath fading, and has become a hot spot in the field of wireless communications. This technology is a key component and probably the most established to truly reach the promised transfer data rates of future communication systems. In MIMO systems, multiple antennas are deployed at both the transmitter and receiver sides. The greater number of antennas can make the system more resistant to intentional jamming and interference. Massive MIMO with an especially high number of antennas can reduce energy consumption by targeting signals to individual users utilizing beamforming.Apart from sub-6 GHz frequency bands, 5G/6G devices are also expected to cover millimeter-wave (mmWave) and terahertz (THz) spectra. However, moving to higher bands will bring new challenges and will certainly require careful consideration of the antenna design for smart devices. Compact antennas arranged as conformal, planar, and linear arrays can be employed at different portions of base stations and user equipment to form phased arrays with high gain and directional radiation beams. The objective of this Special Issue is to cover all aspects of antenna designs used in existing or future wireless communication systems. The aim is to highlight recent advances, current trends, and possible future developments of 5G/6G antennas

A Reconfigurable MIMO Antenna System for Wireless Communications

A reconfigurable antenna system is proposed to improve data throughput limitations in multiple input multiple output wireless communication systems in this investigation. The4×4 MIMO antenna is designed to operate in the 2.4 and 2.6 GHz for  Wireless  Local  Area  Network  (WLAN)  and  Long  TermEvolution (LTE) applications. The system’s radiation pattern re-configurability is  realized by  using the  microcontroller-drivenPIN diode switching concept. Simulations and measurements exhibited good agreements for the single, 2×2 MIMO and 4×4MIMO configurations. The antenna is operational between 2.387to 2.628 GHz, while the simulated and measured reflection coefficients are at least -24.3 dB. All configurations produced anarrow beam forward radiation, while the envelope correlation coefficient (ECC) and diversity gain for the two MIMO configurations are below 0.5 and at least 9 dBi, respectively

Circularly polarized multiple input multiple output transparent antenna

Circular polarization technology can improve mobile connectivity and mitigate signal losses caused by absorption, reflection and refraction by utilizing all planes in transmitting waves. In this thesis, Circularly Polarized (CP) transparent antenna designs are investigated for broadband applications. Two designs are introduced namely Single Input Single Output (SISO) and Multiple Input Multiple Output (MIMO) transparent antennas. A silver coated polyester film which is a Transparent Conductive Oxide (TCO) in the shape of film is incorporated in both designs. The film is cut according to design and attached to a glass substrate. SISO antenna is fed by Coplanar Waveguide (CPW) with a circular ring patch radiating element. The existence of tapered split gap and the inequality in CPW ground arm’s length has contributed to a 3 dB axial ratio bandwidth from 5.4 to 6.2 GHz. Results show that the proposed antenna has a gain of 0.92 dB and an efficiency of 14% at 5.8 GHz. It is shown that the electron mobility, a parameter that is determined by the material development is a primary limiting factor seen from the 14% efficiency of transparent antenna. The proposed antenna obtained a reflection coefficient response from 2.55 to 6 GHz which covers the desired frequency band. MIMO is designed by combining two aforesaid SISO CP antenna designs, mirrored 180° at y-axis and separated by 1 mm. Measurement results show |S11| and |S22| bandwidth from 2.65 to 6.23 GHz with good isolation of 27 dB at the 5.8 GHz band. Envelope Correlation Coefficient (ECC), Mean Effective Gain (MEG) and Diversity Gain (DG) with measurement values of 0.0007, 0 dB and 10 dB accordingly were discussed in the thesis. These values were calculated using scattering parameters data obtained from the measurement. Both designs are meeting the objectives of this project

Passive Planar Microwave Devices

The aim of this book is to highlight some recent advances in microwave planar devices. The development of planar technologies still generates great interest because of their many applications in fields as diverse as wireless communications, medical instrumentation, remote sensing, etc. In this book, particular interest has been focused on an electronically controllable phase shifter, wireless sensing, a multiband textile antenna, a MIMO antenna in microstrip technology, a miniaturized spoof plasmonic antipodal Vivaldi antenna, a dual-band balanced bandpass filter, glide-symmetric structures, a transparent multiband antenna for vehicle communications, a multilayer bandpass filter with high selectivity, microwave planar cutoff probes, and a wideband transition from microstrip to ridge empty substrate integrated waveguide

A Review on Different Techniques of Mutual Coupling Reduction Between Elements of Any MIMO Antenna. Part 1: DGSs and Parasitic Structures

This two-part article presents a review of different techniques of mutual coupling (MC) reduction. MC is a major issue when an array of antennas is densely packed. When the separation between the antennas i