Abstract The growing need of the compact and portable antennas with high speed and low latency wireless communication is the present and future demand of the voice over Internet protocol, on-demand bandwidth, and multimedia applications. Fifth-generation (5G) covers certain low-frequency bands under 6 GHz spectrum, and most of the high-frequency bands under 60 GHz. 5G is the part of the millimeter wave spectrum (30–300 GHz) and is introduced to overcome the problem of spectrum shortage due to exponential enhancement of wireless applications in industry, medical, airborne, radar, satellite, and research fields. The International Telecommunication Union's objective of wireless communications promises to provide higher data rates up to 10 Gbps for 5G mobile users and connectivity to the artificial intelligence devices, along with high spectral efficiencies and enhanced coverage. The users for the 5G require around 5 and 50 Gbps of data rates for low and high mobility, respectively. Beamforming in 5G is the modern powerful technique for the coverage of the intended user/direction using the narrow beam width radiation patterns. A brief survey on 5G beamforming techniques, i.e. analog, digital, hybrid, switched, and adaptive etc. and its types, working algorithms, design of compact antennas, gain, and size/type of the substrates is carried out in this paper. The study of the hybrid coupler, branchline coupler, Wilkinson power divider, and Butler matrix in beamforming is required for 5G smart antennas. Different beam widths like ±15, ±35, ±45, and ±55° etc. are produced for the intended directions using a variety of beamforming techniques. From lower to higher frequency band beamforming applications with Roger's Duroid 4003/4350/5880, tectonic, and aluminum oxide dielectric substrates are discussed here. Various beamforming techniques with their merits, demerits, and applications are included in the paper for the knowledge extension of the beamforming antenna designers and research community.

5G beamforming techniques for the coverage of intended directions in modern wireless communication: in-depth review

A high gain and wideband multiple-input multiple-output (MIMO) for 5G new radio (NR) networks is introduced in this paper. The single unit is a monopole antenna with partial ground plane and two small triangles are cut out from the patch to produce the proposed frequency band. The two elements are located orthogonal to each other in order to reduce the mutual coupling without using isolation structure at the desired frequency 28 GHz. An artificial magnetic conductor (AMC) is located underneath the MIMO antenna to improve the gain by about 55% over the entire achieved frequency band (26-31.5 GHz). The Suggested antenna model with the AMC structure is fabricated to verify the simulation results in terms of S-parameters, radiation patterns, gain, and diversity parameters. It is worth noting that the experimental results have the same trend of the simulation ones which makes the suggested AMC-based MIMO antenna applicable for 5G NR networks.

High gain, wideband and low mutual coupling AMC-based millimeter wave MIMO antenna for 5G NR networks

Abstract Fifth-generation technology is not fully deployed in the world wireless communication till date. Millimeter-wave (mm-wave) band needs to be used due to plenty of available bandwidth and for achieving the goals of 5G such as greater data rate, ultra-high-speed video broadcasting, low latency services, and many more. Wideband antenna is required for 5G applications to access the high speed, low latency Internet services, and ultra-high-definition video streaming. Various bandwidth enhancement techniques have been reported by the researchers for microstrip antennas operating at microwave bands. High link losses, small wavelength, limited coverage, and environmental losses are the major challenges of mm-wave band. To mitigate these issues and satisfy 5G standard, an antenna with wide bandwidth, high gain, narrow steerable beam, high isolation, low side lobe levels, and multiband characteristics is required. Modifications in conventional antenna design techniques are required to achieve broader bandwidth along with stable radiation characteristics, improved gain, and low side lobe levels at mm-wave frequencies. This paper presents the survey of various bandwidth enhancement techniques which has been used in the 5G antennas designed by researchers. Reviews of some wideband 5G antennas with their performance comparisons are also discussed.

Survey of various bandwidth enhancement techniques used for 5G antennas

Fifth generation of the wireless communication rely on modern antenna technologies like massive MIMO and mm-wave band to achieve data rate up to 10 Gbps. This paper presents a design analysis of 1×16 elements tapered antenna array feed with tapered microstrip lines and employing bending lines between the patches. The reported antenna covers −10 dB impedance bandwidth of 27.5 to 28.5 GHz frequency band. The Rogers RT duroid 5880 with 35×28 mm2 is used in the design. The proposed antenna resonates at 28 GHz and has return loss of −50.35 dB with measured gain and bandwidth is 17.9 dBi and 1 GHz respectively. In this design by using the bending transmission line between the patch antennas elements helps to enhance the antenna gain, return-loss and bandwidth and radiation efficiency.

Gain and Bandwidth Enhancement of 28 GHz Tapered Feed Antenna Array

This paper proposed a 1 × 16 antenna array to cover 28 GHz bands for 5G wireless communications systems. The design approach is based on 16-element tapered antenna array with corporate (parallel)-series feed structure network. The individual element of the antenna consists of the inset feed for achieving the proper impedance matching and tapered patch for achieving the desired gain, bandwidth and miniaturization. The whole configuration is designed over a Rogers RT/duroid 5880 dielectric substrate size of 28 × 30 × 0.79 mm3. The measure peak gain is 15.85 dB at 28 GHz. The simulated result shows a return loss of −45.73 dB, bandwidth of 27.56–28.381 GHz, gain of 15.85 dBi and 93.36% of radiating efficiency.

A 28 GHz Corporate Series-Fed Taper Antenna Array for Fifth-Generation Wireless Communication

Fifth generation (5G) is the current hot topic of the world's leading telecommunication companies. The compact designs of antennas made it possible for them to resonate at higher frequencies, thus to enable the devices to attain higher data rate as compared to 4G technology. Data rate of 5G technology for low mobility users is expected to be 50.0 Gbps and for high mobility users it is 5.0 Gbps. On the other hand, International telecommunication union's objective for 5G is 3 times more spectrally efficient thanlong-term evolution (LTE). The paper has carried out meticulous study over the impact of 5G antennas on the size of antenna, size/type of substrate, gain, efficiency, and isolation, etc. Also, different arrays andmultiple input multiple outputs (MIMOs) with patch antenna, magneto electric-dipole, microstrip grid array antenna, folded dipole, series-fed array, connected antenna array, MIMO are studied. The paper also includes the existing technology i.e 4G LTE and their isolation enhancement approaches. Many of the designs used the reflector plates to reduce the back lobe radiation problem in MIMO/array antennas to increase front-to-back ratio. The gain in 5G antennas can be increased by using balun, parasitic element as directors, multiple notch structures, three identical slot sub-arrays, etc. Mathematical equations of multi-element/port antennas are included to model the designed antennas. The beam steering is also included for the 5G technology in this paper.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/1F0B37314022585EBCF690715132421C/S1759078719000382a.pdf/div-class-title-5g-multi-element-port-antenna-design-for-wireless-applications-a-review-div.pdf

5G multi-element/port antenna design for wireless applications:a review

Highly isolated inset-feed 28 GHz MIMO-antenna array for 5G wireless application

With the growing demand of mobile and wireless users, there is a need to switch from fourth generation (4G) to ﬁfth generation (5G) wireless technology for better data rate, coverage, and spectral ...

Millimeter Wave High-Gain Antenna Array for Wireless Applications

To accomplish promises of 5G technology like blazing speeds, massive throughput, capability and ultra-low latency, antennas should be designed having compact designs, high gain, high efficiency, very low return loss, and very low ECC. To achieve all these requirements, researches are required to switch to array and MIMO antennas with low loss tangent substrates such as Rogers Duroid, etc. The proposed design is a combination of an array and MIMO so that all the needed requirements can be fulfilled in 5G in the best possible manner. A 2x8 array-MIMO antenna is designed on Rogers Duroid 5880 substrate with substrate’s dimension of 23.83 x 53.52 x 0.79 mm3. Each patch with inset-feed is uniquely designed with radius, ’r’ = 1.44 mm to achieve sharp peak at 28.0 GHz resonant frequency. The gain of 10.67 dBi and radiation efficiency of 88.2% is achieved at 28.0 GHz in 27.572 - 28.648 GHz frequency band with respect to 2:1 VSWR band.

MIMO antenna design with low ECC for mmWave

In this paper, a wideband 2x2 array MIMO antenna is proposed to cover 5G frequency band. The presented antenna is operational under 2:1 VSWR with -10 dB return loss bandwidth for 21.06 GHz – 29.7 GHz frequency range. The proposed antenna has bandwidth of 8.63 GHz. The isolation between the two ports in the entire band is more than 10.52 dB. With the compact design structure of 15.2 x 7.3 mm2, the proposed antenna offers a gain of more than 3.0 dBi. in the entire band with ECC of less than 10-4 in the whole operating band.

Parul Gupta

Papers

5G multi-element/port antenna design for wireless applications:a review

Highly isolated inset-feed 28 GHz MIMO-antenna array for 5G wireless application

Millimeter Wave High-Gain Antenna Array for Wireless Applications

MIMO antenna design with low ECC for mmWave

2x2 Wideband Array MIMO Antenna for 5G Spectral Band