GHz 5G Research Articles

Packaging and Antenna-Assembled Hybrid Stacked PCB with Novel Vertical Transition for 39 GHz 5G Base Stations

This paper proposes a novel packaging and large-scale antenna-assembled structure for a printed circuit board (PCB) that reinforces productivity, facilitates cost reduction, and maintains reliability. This was achieved by splitting the antenna from the main board and packaging it into a radio-frequency integrated circuit. In addition, two innovative solutions—an externally attachable flexible PCB antenna and a PCB-embedded coaxial line—are introduced to overcome the degradation in antenna performance and vertical RF transition loss in the proposed low-cost hybrid PCB. First, the proposed externally attachable flexible PCB antenna and a parasitic aircoupled antenna, which were easily assembled on the PCB, achieved an antenna efficiency of 95% and an impedance bandwidth of 7 GHz. Second, the fabricated coaxial line exhibited enhanced impedance matching over a wide frequency range of 30–40 GHz and improved insertion loss of approximately 1.4 dB. Furthermore, the packaged antenna, composed of 256 dual-polarized antenna elements per stream, incorporated a 39 GHz CMOS-based 16-channel phased-array transceiver IC. The set-level beam-forming measurements were verified considering an effective isotropic radiated power of 55 dBm at boresight and a steering range >±60°. In addition to being suitable for mass production in terms of cost and reliability, the proposed structures and solutions met the required antenna and beam-forming performance for commercial 39 GHz base stations without sacrificing performance.

A Novel Compact Broadband Quasi-Twisted Branch Line Coupler Based on a Double-Layered Microstrip Line.

A novel quasi-twisted miniaturized wideband branch line coupler (BLC) is proposed. The design is based on bisecting the conventional microstrip line BLC transversely and folding bisected sections on double-layered substrates with a common ground plane in between. The input and output terminals, each with a length of λg/4, and the pair of quarter-wavelength horizontal parallel arms are converted into a Z-shaped meandered microstrip line in the designed structure. Conversely, the pair of quarter-wavelength vertical arms are halved into two lines and transformed into a periodically loaded slow-wave structure. The bisected parts of the BLC are placed on the opposite side of the doubled-layer substrate and connected through four vias passing through the common ground plane. This technique enabled a compact BLC size of 6.4 × 18 mm2, which corresponds to a surface area miniaturization by ~50% as compared to the classical BLC size of 10 × 23 mm2 at 6 GHz. Moreover, the attained relative bandwidth is 73.9% (4.6-10 GHz) for S11, S33, S21, and the phase difference between outputs (∠S21 - ∠S41). However, if a coupling parameter (S41) of up to -7.5 dB is considered, then the relative bandwidth reduces to 53.9% (4.6-10 GHz) for port 1 as the input. Similarly, for port 3 as the input, the obtained bandwidth is 75.8% (4.5-10 GHz) for S33, S11, S43, and the phase difference between outputs (∠S43 - ∠S23). Likewise, this bandwidth reduces to 56% (4.5-8 GHz) when a coupling parameter (S23) of up to -7.5 dB is considered. In contrast, the relative bandwidth for the ordinary BLC is 41% at the same resonant frequency. The circuit is constructed on a double-layered low-cost FR4 substrate with a relative permittivity of 4.3 and a loss tangent of 0.025. An isolation of -13 dB was realized in both S13 and S31 demonstrating an excellent performance. The transmission coefficients between input/output ports S21, S41, S23, and S43 are between -3.1 dB to -3.5 dB at a frequency of 6 GHz. Finally, the proposed BLC provides phase differences between output ports of 90.5° and 94.8° at a frequency of 6 GHz when the input ports 1 and 3 are excited, respectively. The presented design offers the potential of being utilized as a unit cell for building a Butler matrix (BM) for sub-6 GHz 5G beamforming networks.

Singly-Fed Large Frequency Ratio Composite Dielectric Resonator Antenna for sub-6 GHz and mm-Wave 5G Applications

Singly-Fed Large Frequency Ratio Composite Dielectric Resonator Antenna for sub-6 GHz and mm-Wave 5G Applications

Triple Bandstop 2.5D Frequency Selective Surface for Sub-6 GHz 5G Communication

Triple Bandstop 2.5D Frequency Selective Surface for Sub-6 GHz 5G Communication

Metamaterial-based Octagonal Ring Penta-band Antenna for Sub-6 GHz 5G, WLAN, and WiMAX Wireless Applications

Metamaterial-based Octagonal Ring Penta-band Antenna for Sub-6 GHz 5G, WLAN, and WiMAX Wireless Applications

A Miniaturized Metamaterial-Based Dual-Band 4×4 Butler Matrix With Enhanced Frequency Ratio for Sub-6 GHz 5G Applications

A Miniaturized Metamaterial-Based Dual-Band 4×4 Butler Matrix With Enhanced Frequency Ratio for Sub-6 GHz 5G Applications

A DODECAGON SLOTTED CIRCULAR TWO-ELEMENT SUB-6 GHZ FLEXIBLE ANTENNA FOR WEARABLE APPLICATIONS USING MODAL ANALYSIS

The sub-6 GHz 5G band has opened doors for a seamless and high-data-rate communication system connecting multiple devices. Multiple-input/multiple-output (MIMO) antennas are the backbone of such reliable communication systems with enhanced channel capacity. In this paper, a flexible two-element antenna is proposed for wearable applications. The dodecagon-slotted modified circular patch antenna with a defective ground structure gives isolation of 18 dB over the bandwidth. The antenna exhibits a gain of 3.38 dBi at the operating frequency of 4.8 GHz. A characteristic mode analysis was performed to investigate the resonance behavior of the antenna. Furthermore, specific absorption rate analysis was performed and found to be 0.790/0.314 W/kg for 1/10 g of tissue at 4.8 GHz. The MIMO diversity metrics exhibited an envelope correlation coefficient < 0.001, total active reflection coefficient < -10 dB, diversity gain ≈ 10, mean effective gain < -3 dB, channel capacity loss < 0.40 bps/Hz, and multiplexing efficiency < 0 over the operating frequency band.

Low-Cost Multiband Four-Port Phased Array Antenna for Sub-6 GHz 5G Applications With Enhanced Gain Methodology in Radio-Over-Fiber Systems Using Modulation Instability

Low-Cost Multiband Four-Port Phased Array Antenna for Sub-6 GHz 5G Applications With Enhanced Gain Methodology in Radio-Over-Fiber Systems Using Modulation Instability

Novel design and implementation of irregular fractal arrow head structure microstrip antenna for sub 6 GHz 5G applications

Novel design and implementation of irregular fractal arrow head structure microstrip antenna for sub 6 GHz 5G applications

Leaf-Shaped Antennas for Sub-6 GHz 5G Applications

Leaf-Shaped Antennas for Sub-6 GHz 5G Applications

Reconfigurable Compact Wide-band Quad-port Antennas Based on a Varactor Diode for Sub-6 GHz 5G Communications

Reconfigurable Compact Wide-band Quad-port Antennas Based on a Varactor Diode for Sub-6 GHz 5G Communications

Novel Design and Implementation of Irregular Fractal Arrow Head Structure Microstrip Antenna for sub SUB 6GHz 5G Applications

Novel Design and Implementation of Irregular Fractal Arrow Head Structure Microstrip Antenna for sub SUB 6GHz 5G Applications

Connected Slot Array With Interchangeable ADL Radome for Sub-8 GHz 5G Applications

Connected Slot Array With Interchangeable ADL Radome for Sub-8 GHz 5G Applications

Design of a Novel Microstrip Ultra-Wideband Power Divider for WLAN and Sub-6 GHz 5G Applications

Design of a Novel Microstrip Ultra-Wideband Power Divider for WLAN and Sub-6 GHz 5G Applications

Design and Performance Analysis of Defected Ground Slotted Patch Antenna for Sub-6 GHz 5G Applications

Recently, there have been notable advancements in wireless communication systems to address the deficiencies of fourth generation (4G) wireless technology, such as insufficient spectrum bandwidth, slow data transfer rates, and constrained network capacity. These issues may be addressed in fifth generation (5G) wireless technology, which is no longer stand-alone. This article proposes and designs a defected ground slotted patch antenna (DGSPA) for 5G (Sub-6 GHz band) applications. It can work at 3.5 GHz in the 5G N77 band, Sub-6 GHz 5G, LTE Band 42, and WiMAX. The suggested antenna has an overall dimension of 38×38×1.575 mm3 and is built on the Rogers RT5880 substrate material, whose dielectric permittivity is 2.2. The CST software is used as the simulation tool to analyze the designed antenna’s performance. The novelty of the recommended antenna is in terms of its small size with defective ground structure (DGS), high antenna gain, perfect impedance matching, and improved impedance bandwidth. The role of the DGS is evaluated by comparing the antenna’s performance with and without the DGS. It has been noticed that the DGS-backed antenna had an impedance bandwidth improvement of more than 11MHz, whereas the impedance profile is (50.086−????0.179) Ω, which denotes 50 Ω pure resistivity. It will operate within the frequency range of (3.4828 - 3.522) GHz with an impedance bandwidth of 69.2 MHz. The proposed antenna’s reflection coefficient (|????1,1|) is obtained as -54.028 dB at the resonating frequency of 3.5176 GHz, whereas the radiation gain and efficiency are observed as 6.463 dB and 93.475%, respectively. Thus, due to its promising performance based on radiation pattern, optimum efficiency, and higher bandwidth, the recommended defected ground slotted patch antenna can efficiently be used for the application of Sub-6 GHz 5G services.

Asymmetric Coplanar Strip- (ACS-) Fed Side Edge Panel MIMO Antenna for IoT and 5G Applications

For future wireless high-speed wireless applications, the antenna design plays an indispensable role. Electrical compactness has been challenging over the years among the research fraternity. Hence, this paper proposes an electrically compact and miniaturized asymmetric coplanar strip- (ACS-) fed MIMO to bridge this research gap. In MIMO antennas, two electrically small antennas are used and are placed on the edges of the smartphone. A ladder-shaped radiator with a C-shaped slit inserted on the ground plane makes up the antenna’s monopole radiator. A compact antenna is proposed in this paper with dimensions of 0.076 λ×0.409 λ×0.005 λ. This achieves dual band characteristics, which cater to 3.5/5.5 GHz (WiMAX), 5.8 GHz (WLAN), 6.3 GHz (C-band), and sub-6 GHz 5G bands. For the available aperture, reasonable gain is attained by the proposed architecture. Furthermore, fractional bandwidth of 69% and 43% in 2.6 GHz and 5.5 GHz bands, respectively, acting in accordance with the bandwidth stated by Wheeler and Chu’s limit, has been attained in this ACS-fed antenna. In both the operating frequency bands, more than 20 dB isolation between the antenna elements has been achieved. High integrity is attained by the radiation pattern, and actual deployment is granted. Moreover, the simulated results presented are in good accordance with the measured results.

Design and optimization of a deep learning algorithm assisted stub-loaded dual band four-port MIMO antenna for Sub-6 GHz 5G and X band satellite communication applications

In this article, C-type stubs loaded hexagonal shaped four-element MIMO antenna is proposed with improved isolation for sub-6 GHz 5G and X-band satellite wireless communication applications. Initially, the design and simulation studies of the MIMO antenna are performed using Computer Simulation Software (CST) software but its design parameter estimation and optimization consume higher time using conventional EM simulation tools. In order to solve this issue, Deep Learning algorithm-based approach has been proposed to determine the optimal physical parameters along with best possible performance characteristics. This suggested DL based approach is resource and time efficient for parameter estimation and optimization during the design process. To reduce design space and generation of an effective dataset, the feature reduction method (FRM) is implied during the design process. The S-parameters are predicted through Dual-Channel (DC-DNN) Deep Neural Network model. The dual-band MIMO antenna operates with −10 dB impedance Bandwidths of 40 % (2.8 GHz – 4.2 GHz), 38.41 % (6.1 GHz – 9.0 GHz) and shows excellent diversity performance. The proposed MIMO antenna is suitable for Sub-6 GHz n77 (3.3–4.2 GHz), n78 (3.3–3.8 GHz) 5G NR bands and also supports X band satellite (7.25–7.75 GHz and 7.9–8.4 GHz) communication applications.

A penta‐band microstrip slot antenna for S‐, C‐ and X‐band applications

AbstractThis letter presents a compact penta‐band microstrip slot antenna. The proposed antenna comprises a microstrip feed line on the top plane, a polytetrafluoroethylene (PTFE) substrate, and a slotted ground plane. Different shapes of slots and two pairs of horizontal strips on the ground are introduced to achieve five frequency bands. A prototype is fabricated and measured to demonstrate the validity of the design. According to the measured result, the fabricated antenna can operate at five operating frequencies with an impedance bandwidth of 2.41–2.55 GHz (5.65%) for Bluetooth and WLAN, 3.31–3.58 GHz (8.14%) for WiMAX and Sub‐6 GHz 5G applications, 4.52–4.76 GHz (5.17%) for radiometry, 5.10–6.20 GHz (19.47%) for WLAN and ITS, and 10.14–12.40 GHz (20.10%) for radar applications. Moreover, the proposed antenna shows a bi‐directional radiation pattern at each operating band.

Dual-polarized 8-port sub 6 GHz 5G MIMO diamond-ring slot antenna for smart phone and portable wireless applications.

This manuscript presents high performance dual polarized eight-element multiple input multiple output (MIMO) fifth generation (5G) smartphone antenna. The design consists of four dual-polarized microstrip diamond-ring slot antennas, positioned at corners of printed circuit board (PCB). Cheap Fr-4 dielectric with permittivity 4.3 and thickness of 1.6mm is used as substrate with overall dimension of 150 × 75 × 1.6 mm3. In mobile system due to limited space mutual coupling between nearby antenna elements is an issue that distort MIMO antenna performance. Defected ground structure is used to control coupling. The defected ground structure has advantages like ease of fabrication, compact size and high efficiency as compare to other techniques. Less than 30dB coupling is achieved for adjacent elements. The -10 dB impedance bandwidth of 700 MHz is achieved for all radiating elements ranging from 3.3 GHz to 4.1 GHz. The value is about 900MHz for -6dB. The proposed antenna offers good results in terms of fundamental antenna parameters like reflection coefficient, transmission coefficient, maximum gain, total efficiency. The antenna achieved average gain more than 3.8dBi and average radiation efficiency more than 80% for single dual polarized element. The antenna provides sufficient radiation coverage in all sides. The MIMO antenna characteristics like diversity gain (DG), envelope correlation coefficient (ECC), total active reflection coefficient (TARC) and channel capacity are calculated and found according to standards. Furthermore, effect of user on antenna performance in data-mode and talk-mode are studied. Proposed design is fabricated and tested in real time. The measured results shows that proposed design can be used in future smartphones applications. The design is compared with some of the existing work and found to be the best one in many parameters and can be used for commercial use.

Reconfigurable inductorless negative‐refractive‐index transmission‐line metamaterial phase shifter for 5G antenna beam‐steering applications

AbstractA reconfigurable inductorless negative‐refractive‐index transmission‐line (NRI‐TL) metamaterial phase shifter for sub‐6 GHz 5G antenna applications is proposed. The design consists of a microstrip transmission line loaded both in series and in parallel with varactor diodes to provide continuous tuning of the phase of the transmitted signal by varying the bias voltage applied to the varactors, without the need for variable inductor components. The total measured differential phase shift is 190° at 3.2 GHz, with a measured insertion loss of 1.5–2.7 dB in the frequency range of 3.2–3.6 GHz, when the biasing voltage of the varactors is varied between 0 and 7 V. The total size of the microstrip NRI‐TL phase shifter is 19.4 mm × 24 mm. The proposed reconfigurable phase shifter has been incorporated into the feeding network of a two‐element antenna array to demonstrate its use in beam‐steering applications. The measured results for the reconfigurable array show good impedance matching between 3 and 3.35 GHz for all biasing values, allowing continuous beam steering over a scanning range of 60°.