5G Wireless Applications Research Articles

The hybrid pulse amplitude width modulation scheme: high efficiency technique for dimmable VLC systems

Abstract Visible-light communications (VLC) is an environmentally friendly optical wireless communication (OWC) technology that operates in the 400–800 THz frequency band. It is currently a critical technology for 5G and 6G wireless indoor applications due to its high data rates, low latency, and superior reliability. Intensity modulated direct detection (IM/DD) is widely used in VLC systems. A channel modulation scheme is designed using L-level pulse modulation techniques such as on–off keying (OOK), amplitude modulation (PAM), position modulation (PPM), and the width modulation (PWM). We introduce a novel hybrid modulation scheme n-M-PAWM based on both PAM and PWM schemes to improve throughput and significantly increase power and spectrum efficiency in VLC communication systems. The performance of our proposed hybrid n-M-PAWM scheme is studied in several aspects, including the number of transmitted bits per symbol, average BER, information rate ratio (IRR), PAPR, bandwidth, and power requirement. In an extremely noisy VLC system, the proposed 2-M-PAWM modulation outperforms both PPWM and PAPM modulation schemes due to its better BER performances. Additionally, we examine the performance of the VLC system in terms of spectral efficiency (SE) using our proposed PAWM-based dimming control system by varying the number of pulses transmitted during one symbol period. We demonstrate through simulation results that our PAWM-based dimming control system performs significantly better compared to the other pulse modulation schemes. All results of this research show that our proposed hybrid PAWM modulation scheme has high potential for VLC technology in indoor and noisy environments.

New microstrip patch antenna array design at 28 GHz millimeter-wave for fifth-generation application

<span lang="EN-US">This paper presents a study and an array design consisting of two microstrip patch antennas connected in series in a 2×1 form. This antenna provides better performance for the fifth-generation (5G) wireless communication system. The microstrip line feeding technique realizes the design of this antenna. This feed offers the best bandwidth, is easy to model, and has low spurious radiation. The distance between the feed line and the patch can adapt to the antenna’s impedance. In addition, the antenna array proposed in this paper is designed and simulated using the high frequency structure simulator (HFSS) simulation software at the operating frequency of 28 GHz for the 5G band. The support material used is Rogers RT/duroid® 5880, with relative permittivity of 2.2, a thickness of h=0.5 mm, and a loss tangent of 0.0009. The simulation results obtained in this research paper are as: reflection coefficient: -35.91 dB, standing wave ratio (SWR): 1.032, bandwidth: 1.43 GHz, gain: 9.42 dB, directivity: 9.47 dB, radiated power: 29.94 dBm, accepted the power: 29.99 dBm, radiation efficiency: 29.95, efficiency: 99.83%. This proposed antenna array has achieved better performance than other antenna arrays recently published in scientific journals regarding bandwidth, beam gain, reflection coefficient, SWR, radiated power, accepted power, and efficiency. Therefore, this antenna array will likely become an important competitor for many uses within the 5G wireless applications.</span>

A Patch Antenna with Enhanced Gain and Bandwidth for Sub-6 GHz and Sub-7 GHz 5G Wireless Applications

This paper presents a novel microstrip patch antenna design using slots and parasitic strips to operate at the n77 (3.3–4.2 GHz)/n78 (3.3–3.8 GHz) band of sub-6 GHz and n96 (5.9–7.1 GHz) band of sub-7 GHz under 5G New Radio. The proposed antenna is simulated and fabricated using an FR-4 substrate with a relative permittivity of 4.3 and copper of 0.035 mm thickness for the ground and radiating planes. A conventional patch antenna with a slot is also designed and fabricated for comparison. A comprehensive analysis of both designs is carried out to prove the superiority of the proposed antenna over conventional dual-band patch antennas. The proposed antenna achieves a wider bandwidth of 160 MHz at 3.45 GHz and 220 MHz at 5.9 GHz, with gains of 3.83 dBi and 0.576 dBi, respectively, compared to the conventional patch antenna with gains of 2.83 dBi and 0.1 dBi at the two frequencies. Parametric studies are conducted to investigate the effect of the parasitic strip’s width and length on antenna performance. The results of this study have significant implications for the deployment of high-gain compact patch antennas for sub-6 GHz and sub-7 GHz 5G wireless communications and demonstrate the potential of the proposed design to enhance performance and efficiency in these frequency bands.

Compact Circularly Polarized Monopole Antenna Using Characteristic Mode Analysis

This study aims to design a circularly polarized compact antenna using characteristic mode analysis (CMA). The proposed antenna consists of a substrate with a slotted annular ring-shaped patch and partial ground. The excitation position of the antenna and its optimal dimensions are determined through the analysis of different operation modes with CMA. After that, an optimized antenna is designed, and an antenna prototype is fabricated for validation. The experimental results show that the reflection coefficient achieves a -10dB impedance bandwidth of 6.85 GHz, a 3dB-axial ratio bandwidth of 0.7 GHz, and a peak gain of 3.2 dBi. These characteristics agree with simulations and make the circularly polarized compact antenna suit for C-band and sub-6 GHz 5G wireless applications.

PET-BASED FLEXIBLE ANTENNA WITH INKJET PRINTING FOR 5G WIRELESS APPLICATIONS

PET-BASED FLEXIBLE ANTENNA WITH INKJET PRINTING FOR 5G WIRELESS APPLICATIONS

Millimeter-Wave Dual-Band MIMO Antennas for 5G Wireless Applications

This paper suggests a dual-band 28/38 GHz four-element MIMO array based on dual-mode planar monopole antennas for 5G wireless applications. The design structure contains four planar monopole antennas; located at the corners on a 20 × 20-mm2 size Rogers RO4003 substrate with a dielectric constant of 3.55. The proposed planar monopole antenna has the shape of a crescent. In order to achieve the desired behavior and perfor mance, we engraved two rectangular slots on both sides and also added a notch at the bottom. In addition, we used a partial ground plane to enhance the isolation. Significant isolation (> − 23 dB) is achieved between antenna elements by employing spatial and polarization diversity techniques. To validate the design concept, a prototype of the four-element MIMO array is designed, fabricated, and measured. The experimental results show that the proposed antenna can cover the 27.25–29 GHz and 34.5–41 GHz bands with good isolation and high efficiency. Furthermore, the radiation pattern, the realized gain, and the channel capacity are also studied. According to the reached results, the proposed MIMO antenna may be a suitable application-oriented design for 5G MIMO applications at the millimeter-wave range.

Design of Compact 2 × 2 Mimo Antenna for 5G Wireless Application

In this paper, a compact 2 X 2 MIMO antenna is proposed for 5G wireless applications. The proposed 2 X 2 MIMO antenna is designed using four compact circular monopole antennas which are optimized to operate from 3.6 to 57.7 GHz. The antenna structure consists of four orthogonal antenna elements of size 21 mm × 29 mm, which are spaced 1mm apart from each other. The antenna and the defective ground plane are placed on the same side of the substrate. It is demonstrated that MIMO system with 4- antennas produce very good isolation (>-20 dB) without using any additional isolating or decoupling techniques and antenna efficiency is also high. The antenna is simulated using CST Microwave Studio. The simulation results of the proposed MIMO antenna gives good radiation efficiency, Envelope Correlation Coefficient (ECC), improved bandwidth of 54.1 GHz, and optimum radiation characteristics. The proposed compact 2 X 2 MIMO antenna is suitable to operate under 5G wireless applications from 3.6 to 57.7 GHz. The applications of the proposed antenna also include broadcasting satellites, Modern radars, a 5GHz Wi-Fi channel, TV broadcasting satellites and microwave devices

A Reconfigurable Octa-Band Antenna with a High Gain for a Variety of Wireless Applications

The Octa-band frequency reconfigurable antenna proposed in this paper can operate in the UWB, GSM, WiMax, 5G MID BAND, WLAN (C-BAND), WLAN (S-BAND), 5G (C-BAND), and STM link-1 bands. To achieve the desired operating frequency, the ground plane of the UWB monopole antenna is modified by embedding two inverted L-shape slots. A novel frequency selective surface (FSS) reflector consisting of a 5 × 5 array of elements is located at a distance of 0.78λ at 6.2 GHz below the proposed reconfigurable antenna to improve its gain. The addition of FSS resulted in a gain improvement of 3–7 dBi. The proposed antenna has a wide switching capability, allowing it to be integrated into portable electronic devices and making it suitable for 5G and other wireless applications.

28/38 GHz dual-band MIMO antenna with wideband and high gain properties for 5G applications

In this paper, a novel high gain 4-element dual-band multiple-input multiple-output (MIMO) antenna is proposed for fifth generation (5G) wireless applications. A crescent shape is created initially from a circular structure and then the proposed antenna is formed by using slots and Defected Ground Structures (DGS) to set resonances at the desired frequencies. The proposed MIMO antenna operates both at 28 GHz and 38 GHz frequencies. In addition, the MIMO antenna has 3.05 GHz and 2.41 GHz bandwidth at those frequencies, respectively. The antenna elements are orthogonally placed to each other as a design concept to enhance the isolation between the elements up to 30 dB. Moreover, the MIMO antenna has maximum measured gains of 8.14 dB and 8.04 dB at 28 GHz and 38 GHz, respectively. The antenna size achieves compactness with the total size of 60 × 60 × 0.508 mm3. The designed MIMO antenna is also evaluated in terms of important MIMO parameters such as diversity gain (DG), envelope correlation coefficient (ECC), mean effective gain (MEG), and channel capacity loss (CCL). The proposed antenna is a great candidate for modern 5G applications that require both wideband and high gain properties with its MIMO antenna parameters of DG, ECC , MEG and CCL.

A Wideband CMOS Power Amplifier With 52% Peak PAE Employing Resistive Shunt Feedback for Sub-6 GHz 5G Applications

This letter presents the design and implementation of a wideband power amplifier (PA) for sub-6 GHz 5G wireless applications. The PA employs a Class-B biased cascode topology with resistive shunt–shunt feedback for wideband response, good linearity, and simultaneous input and output matching. The design equations and stability considerations are laid out and are followed by experimental validation using both static and dynamic measurements. The chip prototype was fabricated in TSMC’s 65 nm CMOS technology. The PA operates from a 3.3 V supply and delivers a maximum power gain of 22.5 dB with a bandwidth of 2.17 GHz between 0.33 and 2.5 GHz, a peak output power of 21.5 dBm, and 52.4% power-added efficiency (PAE) at 1 GHz with >35% PAE over the operating frequency range. In the measurement of an orthogonal frequency-division multiplexing (OFDM) signal with 20 MHz modulation bandwidth and 10 dB peak-to-average power ratio (PAPR) at the average output power of 11 dBm around 1 GHz, EVM of −39 dB was achieved using memoryless polynomial-based digital predistortion (DPD).

Tri-band Dual Substrate Aperture Coupled Microstrip Antenna for C, X, and Ku Band Applications

The design work presents a triple Y-fed dual substrate aperture coupled microstrip antenna that operates in C, X, and Ku bands. The overall dimension of the antenna is 50*40*1.894 mm. The antenna has four layers with two dissimilar substrates. A unique triple Y-structured feed line connected to a quarter-wave transformer forms the first layer of the design and shows a greater impact on impedance matching. A superimposed modified defected ground structure is sandwiched between two dissimilar substrates, FR4 and RT5880. The FR4 substrate is placed above the triple Y feed structure over which superimposed DGS is placed to obtain enhanced bandwidth. The third layer is formed by placing the second substrate RT5880 above the ground plane. The dielectric constant of the lower substrate is considered higher than the upper substrate to avoid undesired radiations at unwanted frequencies. A patch with three rectangular slots is placed over the RT5880 substrate for having tri-band characteristics. The patch is excited effectively through the slots in the ground plane thereby enhancing the coupling between the patch and the feed resulting in maximum radiation of RF energy. With this, an enhanced bandwidth of 12.66%, 16.67%, and 7.19% in all three bands is attained. Besides, the proposed design has a gain of 3.265 dBi at the C band, 3.305 dBi at the X band, and 4.385 dBi at the Ku band. The fabricated antenna is tested and the results are compared for both simulated and measured values. The results emphasize that a tri-band antenna can be used effectively in operating frequencies including the 5G wireless application band.

Design of a Novel Capsule-Shaped Compact UWB Antenna for 5G Wireless Applications

Design of a Novel Capsule-Shaped Compact UWB Antenna for 5G Wireless Applications

Design of Six Element MIMO Antenna with Enhanced Gain for 28/38 GHz mm-Wave 5G Wireless Application

The fifth-generation (5G) wireless technology is the most recent standardization in communication services of interest across the globe. The concept of Multiple-Input-Multiple-Output antenna (MIMO) systems has recently been incorporated to operate at higher frequencies without limitations. This paper addresses, design of a high-gain MIMO antenna that offers a bandwidth of 400 MHz and 2.58 GHz by resonating at 28 and 38 GHz, respectively for 5G millimeter (mm)-wave applications. The proposed design is developed on a RT Duroid 5880 substrate with a single elemental dimension of 9.53 × 7.85 × 0.8 mm3. The patch antenna is fully grounded and is fed with a 50-ohm stepped impedance microstrip line. It also has an I-shaped slot and two electromagnetically coupled parasitic slotted components. This design is initially constructed as a single-element structure and proceeded to a six-element MIMO antenna configuration with overall dimensions of 50 × 35 × 0.8 mm3. The simulated prototype is fabricated and measured for analyzing its performance characteristics, along with MIMO antenna diversity performance factors making the proposed antenna suitable for 5G mm-wave and 5G-operated handheld devices.

High-Isolation Wide-Band Four-Element MIMO Antenna Covering Ka-Band for 5G Wireless Applications

High-Isolation Wide-Band Four-Element MIMO Antenna Covering Ka-Band for 5G Wireless Applications

Design and Parametric Analysis of a Triple Band Waxing Crescent Moon Shaped Slotted Microstrip Patch Antenna for 5G Wireless Communications

In this article author designs a new and compact patch antenna with the dimensions 40x21x1 mm3 on substrate called FR4 with a dielectric constant of 4.4, sandwiched between a patch and a copper ground plane. Microstrip feedline is used to link the Moon-shaped antenna to the coaxial cable connection and the antenna's impedance is matched. slotted antenna has been found to resonate between the frequency bands of 23.67-24.82 GHz,25.46 -26.44GHz and 26.77-27.92 GHz at resonant frequency of 24.32 GHz ,25.91GHz and 27.36 GHz respectively. at all the resonant frequencies of 24.32 GHz ,25.91GHz and 27.36 GHz, VSWR of the proposed antenna is same with the value 1.06 dB. Microstrip feeding technique is used to create this microstrip patch design. This patch is being researched because it has a low VSWR at all the three resonant frequencies with high bandwidth. This design is suitable for triple band operations for wireless communication in the range of 5G frequency bands. By adopting an appropriate feeding mechanism and use of proper cutting slots in the rectangular patch, frequency band width can be increased. The electromagnetic simulation of the proposed antenna has been done using CST software. The analysis of performance will be based on changing the geometry of the patch and the obtained results are gain, VSWR, antenna efficiency and radiation pattern. After parametric analysis it is observed that this design is perfectly suitable for 5G wireless applications. KEYWORDS: Moon shape, Patch antenna, gain, 5G.

(Digital Presentation) Substrate Effects in GaN-on-Si Hemt Technology for RF FEM Applications

: GaN-on-Si HEMTs are emerging as a viable candidate for front-end-of-module (FEM) implementation in 5G and beyond user equipment and small-cell applications [1][2]. This is because GaN HEMTs based power amplifiers and switches have high power handling capability as well as excellent switch figure-of-merit (Ron × Coff). The cost-effective integration of GaN HEMTs on silicon substrates not only benefit from standard CMOS back-end-of-the-line processing but also wafer-level integration with Si-CMOS [1][3], enabling complex functionality and better performance than the standalone counterparts. An example can be a hybrid beamformer where GaN HEMTs can enable much smaller antenna array and therefore a smaller system form factor. For 5G wireless applications, standalone or co-integrated GaN HEMT based FEMs can lead to a more energy efficient and compact system as compared to standalone Si-CMOS technologies. However, for both amplifiers and switches, GaN-on-Si HEMTs present thermal management and substrate loss related issues. In this work, we study and model the impact of GaN HEMT integration on Si substrate on RF substrate losses and non-linearities. The growth of III-N buffer is the most significant factor in determining RF losses and harmonic distortion contribution from the substrate. High temperature annealing and ion implantation steps encountered during HEMT processing can also degrade the substrate performance. In addition, we demonstrate a direct co-relation between substrate losses and harmonic distortion analogous to silicon-on-insulator technologies (Figure 1). However, the bias dependence of RF losses and harmonics show a strong time dependence (memory effects) which is more complex to model [11]. We discuss the approaches to understand and model these effects.

Smart, Fast, and Low Memory Beam-Steering Antenna Configurations for 5G and Future Wireless Systems

Smart Antennas are important to provide mobility support for many enhanced 5G and future wireless applications and services, such as energy harvesting, virtual reality, Voice over 5G (Vo5G), connected vehicles, Machine-to-Machine Communication (M2M), and Internet of Things (IoT). Smart antenna technology enables us to reduce interference and multipath problems and increase the quality in communication signals. This paper presents a number of nonlinear configurations of dipole arrays for forming a single beam in any desired direction. We propose three, four, six, and eight-element array structures to perform this single beam-steering functionality. The proposed array configurations with multiple axes of symmetry (in the azimuthal plane) decrease the computational repetitions in optimizing respective weight factors for beam-steering. The optimized weight factors are obtained through the Least Mean Square (LMS) method. MATLABTM is used to calculate optimized weight factors as well as to determine the resulting radiation patterns. Since antennas are bidirectional elements, beamforming in one direction means that the antenna will also have high receiving gain in that direction. Performances of differently configured models are compared in terms of their directivity, sidelobe reduction, and computational complexities for beam-steering.

A low‐profile rectangular slot antenna for sub‐6 GHz 5G wireless applications

SummaryThis paper proposes a novel planar rectangular slot antenna designed and fabricated for a sub‐6 GHz 5G wireless application. The proposed design can work in sub‐6 GHz 5G, WiMAX, and LTE Band 42. The antenna has an inverted stub and E‐shaped and rectangular radiating slot with a circular parasitic element on its upper side concurrently activated by a microstrip feed line with a two‐folded T‐shaped design. The proposed antenna covers the 5G N77 band at 3.5 GHz. It has a dimension of 32.4 × 27.9 × 1.6 mm3 with good reflection coefficient characteristics and excellent impedance matching. The reflection coefficient (S11) is found at −26.5 dB, and the resonant frequency is 3.5 GHz, with a peak gain of almost 4.2 dB. The proposed antenna has ≈82% efficiency for the whole frequency band and provides 19 MHz of total bandwidth. Finally, the proposed antenna is an attractive solution for sub‐6 GHz 5G wireless applications.

Microstrip Patch Antenna Design with Artificial Magnetic Conductor (AMC) at 26 GHz

Advancements in 5G wireless communication systems are expected to enhance the communication capability significantly to achieve the higher data rate by accommodating broad bandwidth. In this paper, three compact sizes of rectangular microstrip patch antennas that were made of RT5880, FR-4 and RO3003 substrates with 0.5 mm thickness and resonating at 26 GHz were proposed for the 5G applications. However, the antenna having narrow bandwidth and low gain which contributes to drawback of this microstrip patch antenna design and hence an Artificial Magnetic Conductor (AMC) was proposed to overcome this drawback. The 3.5 mm  3.5 mm rectangular loop-slot AMC was designed at 26 GHz using FR-4 and it is found that integrating the AMC structure to the printed patch antenna significantly improved the gain and directivity of the antenna. With the help of AMC design, for RT5880 patch antenna, the gain increased for approximately 5% from 6.04 dBi to 6.34 dBi. Besides that, RO3003 patch antenna gain improved for 78.62% from 4.77 dBi to 8.52 dBi and for FR-4 patch antenna, the gain escalated from 2.24 dBi to 7.86 dBi (roughly 251% increment). As a conclusion, the directivity of RT5880 substrate solely decreased for approximately 13.75%. Meanwhile for RO3003 and FR-4 patch antennas, with the assist from AMC design, the directivity of antenna escalated for more than 120 % compared to without AMC and this proved that this design has potential to be used for 5G wireless networks and applications.

Broadband circularly polarized 2 × 2 MIMO array for midband 5G wireless applications

Abstract The novel compact size orthogonally fed 2 x 2 Multiple Input and Multiple Output (MIMO) array antenna for mid-band Fifth Generation (5G) wireless application is presented. The antenna configuration consists of diamond-shaped patches employed at the top of substrate. The V-shaped common ground slot structure is employed at the bottom of substrate. A broadband circular polarization is achieved by simply combining two circular polarization modes obtained from ground V slot and top patch feed structure. Mainly, the impedance bandwidth (IBW) and gain are enhanced by protruding slots on ground and cutting edges of patches. The measured result shows that 1.70 – 8.00 GHz (6.30 GHz) of IBW, 8.8 dBic of peak gain, and 3 dB axial ratio bandwidth from 1.81 – 3.87 GHz (2.06 GHz) are obtained. The proposed antenna performances are experimentally validated by fabricating and testing it for measured result analysis without using power divider.