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Designing an electromagnetic radiating element that can enhance the capacity of a device operating with multiple frequencies simultaneously, while maintaining its compactness and compatibility with customer premise equipment, is a significant challenge. To tackle this issue, this work proposes a multiple input multiple output (MIMO) antenna with eight elements placed 45° apart on a Rogers 5880 substrate which has been micromachined from sixteen edges with a thickness of 0.252 mm. The substrate measures the area of 717.46 mm2 boasting a dielectric constant of 2.2 and loss tangent of 0.0009 with a unique star shape. The slot technique improves the return loss accompanied by defected ground structure to achieve dual-band operation at 28.1 GHz (n261) with the impedance bandwidth from 27.95 to 28.4 (0.45 GHz) and 39.5 GHz (n260) having impedance bandwidth from 38.6 to 40.4(1.8 GHz). The inter-element isolation of more than 60 dB is achieved for both bands with micromachined substrate. The measured gain at 28 GHz is 7dBi and at 39 GHz it is obtained as 7.4dBi. The 8-port MIMO is simulated for all the diversity metrics such as Diversity Gain (DG), Channel Capacity Loss (CCL), Envelope Correlation Coefficient (ECC), Mean Effective Gain, Total Active Reflection Co-efficient (TARC). The parameters evaluated for all eight ports are within the standard values with ECC of < 0.001, DG > 9.99 dB, CCL < 0.1b/s/Hz, and the TARC < − 10 dB. The MIMO has been fabricated and tested for various results which favourably aligned with the simulated results validating the applicability of the proposed mm-Wave 8-port MIMO antenna for practical 5G applications. Furthermore, the 8-port is also simulated for conformality check which showed a minor change in impedance bandwidth at 15°, 30°, and 45°. The Specific Absorption Ratio (SAR) analysis has provided values less than 1.6 W/kg for both the intended bands. The conformal and SAR analysis has added an advantage to the application of the proposed antenna for 5G as well as for wearable on-body applications. [ABSTRACT FROM AUTHOR]

According to the critical challenges for accessing streaming multimedia over wireless technologies such as lower ranges of data throughput and unacceptable rates for delay and packet losses, it was necessary to implement a system that makes some processes for these challenges, with considerations of coverage and capacity limitations that definitely will have a direct effect on the overall system quality. In this paper, we discuss the effect of applying radio resource management (RRM) technique and smart antenna modes through the fifth-generation (5G) radio link on the voice streaming packets flow in a network where many scenarios were simulated by OPNET while maintaining the quality of the network, regardless of the data load inside it. Also, we have a proposed algorithm to utilize RRM and smart antenna modes over 5G networks. On the other hand, we make a detailed eleven scenarios divided into two phases to discuss the effect of these parameters on quality as (i) RRM Coverage and system capacity, and (ii) smart antenna modes in terms of coverage and capacity. The results of simulation prove that adding RRM and smart antenna modes to the proposed networks over 5G radio link verifies a considerable evolution in the network on data flow of streaming voice packets, also including that end to end delay, packet delay variations, and throughput realize the overall requirements for quality of service (QoS) to access multimedia streaming services through a wide range of 5G bandwidth. The proposed system support monotonically response of delay all over the time of simulation for all QoS metrics. [ABSTRACT FROM AUTHOR]

This study introduces a novel, highly compact broadband millimeter-wave (mm-wave) antenna design and its Multiple-Input-Multiple-Output (MIMO) configuration proposed for 28 GHz applications targeting 5G networks. The antenna is designed over a 0.25 mm thick Rogers RT5880LZ substrate having a relative dielectric permittivity of 2 and an overall size of 16 mm × 16 mm. Its MIMO configuration utilizes polarization diversity and includes four elliptical-slot radiators integrated with microstrip-line structures, specifically optimized for 28 GHz operation. The performance of the proposed mm-wave MIMO configuration is validated through simulation of its S-parameters using CST software and measurements obtained with a vector network analyzer (VNA). The proposed antenna demonstrates excellent S-parameter performance, achieving a gain of up to 6 dBi and a radiation efficiency of 94% across the operational frequency band. Each antenna element exhibits an impressive wide operating bandwidth of 9 GHz, spanning from 22.2 to 31.4 GHz at a − 10 dB threshold. Evaluations of the MIMO system's performance indicate promising results, including an exceptionally low envelope correlation of about 10 - 5 and a diversity gain of around 10 dB throughout the operating bandwidth. The design also ensures significant isolation between MIMO elements without requiring decoupling structures. A physical prototype of the proposed antenna is fabricated and subjected to measurements, depicting a strong corelation between the measured and simulated data, with some minor variations attributed to fabrication tolerances and cable losses. Comparative analysis further emphasizes the potential viability of the proposed MIMO antenna positioning it as a viable candidate for future compact-sized mm-wave MIMO systems. [ABSTRACT FROM AUTHOR]

A small MIMO antenna for use in dual bands is designed, simulated, and implemented in this work. Initially, a patch antenna was constructed and simulated, with further adjustments made to its size to achieve a dual-band performance at frequencies of 4.8 GHz and 6.8 GHz. A MIMO structure consisting of two elements is designedwith a partial ground plane. The electrical dimension of the antenna is 0.079λ × 0.0382λ at 4.8 GHz. The findings indicate that the MIMO antenna design demonstrated effective performance across intended frequency bands with 10 dB impedance bandwidth. The antenna displayed an essentially omnidirectional radiation pattern and achieved a satisfactory level of gain up to 5 dBi. The obtained findings exhibit promise, therefore establishing the suggested antenna as a viable option for 5G applications. The designed antenna is manufactured and practically tested in order to evaluate it's fundamental characteristics, including reflection coefficient and radiation pattern. These experimental findings were then compared to the outcomes obtained through simulation, resulting in a satisfactory consensus between simulated and measured results. [ABSTRACT FROM AUTHOR]

With the increasing user density of wireless networks, various user partitioning techniques or algorithms segregate users into smaller, more manageable clusters. The benefit of user clustering techniques in non-orthogonal multiple access (NOMA) is to optimize resource allocation and improve network performance, spectral efficiency, and user fairness in next-generation wireless networks, particularly in scenarios with a high density of users and diverse channel conditions. With increasing users, the network creates clusters before implementing non-orthogonal multiple access within these clusters. In this paper, we have organized and classified various user clustering techniques deployed from the perspective of NOMA-based communication in the current era. Furthermore, researchers have highlighted some works deploying joint resource allocation and clustering optimization based on various criteria to enhance the overall sum rate of the network. We also identify low-complexity user clustering techniques for multiple applications, e.g. the Internet of Things, unmanned aerial vehicles, and reconfigurable intelligent surfaces in the 5G and beyond communication networks. [ABSTRACT FROM AUTHOR]

A Substrate Integrated Waveguide (SIW) antenna has been presented here with a single element, which could be effectively tuned betwixt 28 and 38 GHz. By turning off one of the two PIN diodes, which were utilized as switches, a change is achieved in the antenna's resonant frequency as of 28–38 GHz. Additionally, two separate frequencies will be obtained whilst flipping both switches off. In the antenna design, there is sufficient gain along with efficiency to gratify 5G requirements. This could be accomplished by altering the antenna's SIW layout. An inset curvature has been featured by both the ends betwixt the tapered section and the SIW cavity, which alters the structure. As a result of the tapered section, superior impedance matching is achieved. A wide range of possible configurations has been offered by this reconfigurable SIW antenna by utilizing the Roger 5880 substrate along with a K-type connector input. The antenna responds with 7.16 dBi of gain and 94% efficiency at 28 GHz when S1 is disabled and S2 is enabled. Similarly, the antenna responds with a gain of 10 dBi and an efficiency of 88% at 38 GHz when S1 is on and S2 is off. When every PIN diode are turned off, the antenna enhances by 7.09 dBi for 28 GHz whereas it improves by 10.7 dBi for 38 GHz. To run the simulations, the CST Studio Suite was utilized; subsequently, the outcomes obtained are in good agreement with the predictions made by the program. [ABSTRACT FROM AUTHOR]

This work presents a hybrid ring-mesh topology based passive optical network with free space optics (PON/FSO) model for bidirectional transmission at 10 × 10/10Gbps throughput to offer information to the fiber-FSO subscribers simultaneously with enhanced disaster resilience and fault protection capability. Fiber impairments, FSO link weather and turbulent conditions' tolerance can be enhanced by using a new two-dimensional modified fixed right shifting (2D-MFRS) code for upstream and downstream transmission through integrated fiber-FSO links. A PON/FSO model using 2D-MFRS code is a promising network that raises the network reliability, security and survivability, especially in rural places where the core fibre link may be damaged or destroyed. The obtained numerical and simulation results show that proposed model provides 90–130 km fiber range with fixed 100 m FSO range. FSO range of 850–1900 m with fixed 10 km fiber length can be obtained concerning weak-to-strong turbulent as well as distinct weather conditions. Also, hybrid ring-mesh topology is able to sustain −11 to −18dBm receiver sensitivities in wired-wireless transmission. The proposed model is also capable to handle 130 to 160 subscribers at symmetric 50Gbps/channel throughput. At acceptable bit error rate, low power penalty of 1 dB and −24 dB power budget are observed between back-to-back and integrated fiber-FSO link. Additionally, high signal to noise ratio of 95 dB can be maintained effectively by the system supporting 10 optical units per remote node and it also shows successful transmission upto 1:64 split ratio. Finally, the comparative literature work reveals that the proposed model offers security, long-reach, high transmission rate, and cost-effectiveness for fifth generation fronthaul/backhaul networks. [ABSTRACT FROM AUTHOR]

An FSS based electromagnetic (EM) shield for 5G, X-band and Ku-band indoor shielding applications is proposed in this manuscript. This shield offers a tri-band and polarization-insensitive behavior. A wide rejection bandwidth (10 dB) of atleast 1400 MHz, 3200 MHz and 1100 MHz for 5G, X and Ku-band is observed. The design incorporates meandered square loop (MSL) and slitted Jerusalem cross (SJC) provides shielding for the targeted bands while offering excellent incident wave angular stability up to 75 degrees. In addition to this, a lumped circuit model, metamaterial (MTM) characterization and finite element boundary integral equation (FEBI) investigations are also performed to evaluate and confirm the performance of the FSS. Dual meta-material characteristics are observed including ENG (epsilon-negative)/MNG (mu-negative) while achieving at least 30 dB shielding effectiveness (SE). [ABSTRACT FROM AUTHOR]

The telecommunications industry is one of the fastest growing sector. Technological upgradation is required every year to provide better service quality, coverage and capacity and providing more new features. Fifth generation (5G) is the most recent mobile generation that will offer high-speed internet and data services, minimal-latency services, reliable connections, ultra-high resolution multimedia services, and access to billions of devices which leads to possible the applications such as fully automated production industries, driverless autonomous car, tele-surgery and many more. 5G mobile networks will provide better service quality, coverage and capacity. Larger bandwidth is necessary to provide high data rate services. Due to a lack of frequency spectrum, the currently utilized microwave band is incapable of meeting the 5G objective. So, while the mm-Wave spectrum has a huge number of frequency bands available, high link loss and environmental absorptions are key limits that may be solved by constructing a wide band antenna with high gain, high efficiency, and a steerable narrow radiating beam. The most crucial component of a wireless communication system is the antenna, which transmits and receives radio waves. Microstrip antennas are popular for a variety of applications because to their small size, light weight, low profile, and simple fabrication, but they have some limitations, including low radiation efficiency, low gain, restricted bandwidth, and others. There are several problems and major issues that have yet to be resolved. To attain high performance, low cost, and planar layout, upcoming 5G technology necessitates certain alterations in standard antenna design methodologies. The objective of this study is to address 5G antenna design challenges and barriers, as well as to identify research gaps in this area. It will also cover possible antenna technologies used in antenna design, a review of some recently created antenna solutions, and performance comparisons. To attain the higher performance necessary for 5G and to solve design difficulties, many approaches such as massive MIMO, electromagnetic band gap, substrate integrated waveguide, metamaterials, metasurface, artificial magnetic conductor, dielectric superstrate, butler matrix, and others have been used in 5G antennas. Every approach has advantages and disadvantages, which are explained in this paper. By appropriately combining these strategies, one may obtain the requisite antenna performance for 5G. A review of current developments in 5G antennas based on these approaches is reviewed, along with their merits and limits. [ABSTRACT FROM AUTHOR]

In this letter, a reconfigurable single elemental Substrate Integrated Waveguide (SIW) antenna is developed aimed at operating at 28 GHz as well as 38 GHz. The two PIN diodes used as switching elements shift the antenna resonance between 28 and 38 GHz when one of them is switched off. Also, dual bands are realized when both switches are made off. The developed antenna provides sufficient gain and enhanced efficiency to meet the requirements of 5G. This is accomplished by structural modifications of the SIW structure by stretching the flaring part of the tapered section introduced in the antenna. The tapered section provides good impedance matching. This reconfigurable SIW antenna uses Roger 5880 substrate and input coupling of K type connector. When S1 is turned off and S2 is turned on, the antenna responds at 38 GHz with a surge of 9.42 dBi along with 97.49 percent efficiency. As S1 is turned on and S2 is turned off, the antenna responds at 28 GHz with an increase of 7.33 dBi together with an efficiency of 98.54 percent. The antenna has a dual band response at 28 GHz along with 38 GHz with a gain of 7.23 dBi together with 9.6 dBi, and efficiency percentage of 99.14 percent and 96.96 percent when all PIN diodes are turned off. The simulations were performed using CST Studio Suite along with the computed outcomes are established in a better agreement with the simulation results. [ABSTRACT FROM AUTHOR]

Owing to the variety of powerful smart mobile devices (e.g., iPhone, iPad, Android) handling a wide range of traffic including multimedia, it was recommended to use the salient features of 5G networks that have been developed for high-bandwidth applications to support robust aspects for power saving mechanisms. Furthermore, there are additional advantages in using DRX, such as over-the-air resource-saving on both the uplink and downlink to increase overall system capacity. In particular, care should be exercised for real-time services. This study focused on propose powerful power optimization modes as DRX mode and Smart DRX parameters to realize appropriate rates for power saving with the higher quality of multimedia services, as well as ensuring the effectiveness of using smart DRX short cycles and smart DRX long cycles on multimedia services and the overall performance. By using real-time OPNET Simulator 17.5, simulations results had been verified that the smart DRX mechanism is better in quality of saving compared with the other DRX modes, it also ensured that smart DRX long cycles represent a better mechanism for accessing all multimedia services in terms of standard performance criteria. [ABSTRACT FROM AUTHOR]

This article presents a ± 45° dual-polarized triple-band dipole antenna array for 5G base station applications. Each antenna element consists of three main parts: radiator, feeding baluns, and reflector. The profile antenna array is designed to cover two bands from n77 and one band from n79 5G NR frequency spectrum. The proposed antenna element and array are optimized with ANSYS 18.2 HFSS simulator and then fabricated and fully characterized. The obtained measured impedance bandwidths resulted in 3.6–3.75 GHz, 4.1–4.25 GHz, and 4.82–4.95 GHz, with a gain of almost 8.12 dBi and 70.7° half-power beam width (HPBW). Once characterized, such an elementary element has been used in the design, realization and test of a 1 × 8 antenna array that exhibited a measured gain 16.65 dBi with 69° HPBW respectively. The antenna array operates in 3.43–3.75 GHz, 4.13–4.30 GHz, and 4.80–4.95 GHz with 15 dB return loss. The triple-band dual-polarized feature with very high isolation, cross-polarization discrimination ratio (XPD) and front to back ratio (FBR) makes this profile antenna array a suitable candidate for 5G base station applications. [ABSTRACT FROM AUTHOR]

Massive Multiple Input Multiple Output (m-MIMO) or Large Scale Antenna System (LSAS) is the latest version of cellular network technology with the purpose to send data from the base station to different users. The huge determined expansion in the mobile equipment and data rate requirement has created the rigid necessity for future wireless communication networks. The m-MIMO envisages a significant increase in the capacity but at the verge of excessive hardware complication. In this paper, we put forward a less complex precoding scheme based on the hybrid architecture to achieve a performance higher than the conventional baseband Minimum Mean Square Estimation (MMSE) precoding. In this paper, we propose a precoding schema namely amplitude and phase MMSE (APMMSE) to attain the performance of traditional MMSE precoding. The informed greedy best-first search has offered to estimate the baseband precoding matrix. It formulates the amplitude of the baseband precoder. Radio Frequency Precoder modifies the phase and provides an optimal signal-to-interference -noise ratio SINR and thus improves spectral efficiency of hybrid architecture. [ABSTRACT FROM AUTHOR]

Millimeter wave (mmWave) wireless technology has become a part of human life for high-speed and secure data transmission. This paper presents a square-slotted microstrip patch antenna at 37 GHz resonant frequency for mmWave wireless communication. The antenna consists of one H-slot and one inverted T-slot loaded over the radiating patch. The proposed antenna has been designed and investigated on Rogers RT5880 substrate with relative permittivity 2.2 and loss tangent 0.0009 using Electromagnetic Simulation Software CST Microwave Studio. The result of this paper shows minimal return loss −43.05 dB, gain 8.18 dB, and impedance bandwidth 16.22% at 37 GHz resonant frequency. The voltage standing wave ratio (VSWR), E-plane, and H-plane radiation pattern has also presented for the proposed antenna which can be strong candidate for 5G mmWave cellular communication. [ABSTRACT FROM AUTHOR]

Massive multiple-input multiple-output (MIMO) is a crucial technology platform for the fifth-generation of cellular systems (5G). However, massive MIMO systems are affected by pilot contamination, which influences the data rate of the system. This contamination is caused by the non-orthogonality of the pilot sequences transmitted by users in a cell similar to the neighboring cells. The current study proposes a channel-estimation scheme that employs comprehensive knowledge of large-scale gained by applying an orthogonal pilot reuse sequence to eliminate pilot contamination in edge users with reduced channel quality based on the approximation of large-scale fading, and the performance of this scheme is evaluated using the maximum ratio transmission and zero-forcing precoding techniques. Largely interfering users in neighboring cells are established based on an estimation of large-scale fading, and these users are included in the joint channel processing. The channel quality of users is enhanced by allocating orthogonal pilot reuse sequences to the center user and the edge users based on their levels of pilot contamination estimated from the large-scale fading to mitigate this problem when the number of antenna elements M is infinite. The findings of the simulation indicate that improved channel approximation and reduced performance loss could lead to a high data rate. [ABSTRACT FROM AUTHOR]

Centralized radio access network (CRAN) is getting considerable attention in 5G radio access network infrastructure because of supporting deployments of small cells at a massive scale. In particular, CRAN enables network operators to enhance network coverage and capacity without interference with one cell solution and centralized radio processing. This centralization decreases both the network capital and operational expenditures. However, all these technological advancements bring considerable challenges in the transport infrastructure of 5G such as the evolution of the mobile front haul (FH) interface which imposes strict latency and bandwidth requirements on the transport layer. In this paper, the architectural changes that CRAN brings in 5G cellular networks and the intrinsic demands of the FH transport network is discussed. Different techniques that constrain FH requirements to make it cost-efficient are also surveyed. The overall motivation of this work is to achieve the optimal FH transport solution through a passive optical network. [ABSTRACT FROM AUTHOR]

We introduce the basic concept, background, and development of mobile communication systems from the first generation (1G) to the fifth generation (5G) including their antenna systems. We also describe the requirements for 5G networking and optimization of antenna systems, and present the basic principle of three-dimensional array antennas. Weight optimization methods of massive multiple-input multiple-output (MIMO) antennas are proposed and verified. Finally, several ideas are given to solve the problem of power consumption of 5G antenna systems. [ABSTRACT FROM AUTHOR]

In fifth generation heterogeneous network, small cell is developed to compensate the growing demand for mobile data services. Due to the smaller size of cell, users have a short duration of connection, however, the user may also have the need of handoff frequently. At the time of handoff, different networks are available with different data rate and different other parameters. So, there is the need of frequent selection for the optimal network. In this paper, a utility-aware optimization algorithm has been proposed for network selection in a heterogeneous environment of Wi-Fi, WiMAX, WLAN, LTE, UMTS, and GPRS network. The weight factor is proposed for modified Jaya algorithm which is calculated by the analytical hierarchical process, standard deviation, and entropy method. Different applications are considered such as video, voice, web browsing and email transfer in which available bandwidth, packet jitter, packet loss, cost per byte are taken as dominant attributes, respectively. According to the dominant factor, different networks are selected for different applications because the requirement of all applications cannot be fulfilled by one network. Finally, the proposed algorithm is compared with multi-attribute decision making algorithms and game theory and accuracy of the proposed algorithm is calculated. The accuracy of proposed algorithm is higher as compared to the other algorithms and at the same time, this algorithm requires less computation which can further reduce the handoff latency and failure probability. Hence, the performance of handoff can be improved by using modified Jaya algorithm. [ABSTRACT FROM AUTHOR]

We study the performance of space division multiple access (SDMA) under a non-ideal engineering situation. When the SDMA channel is of high inter-layer correlation and the condition number is large, the multiple user multiple input and multiple output user equipment (MUMIMOUE) grouping should be optimized, and in some cases further dimension-reduction should be applied. As the channel measuring is always non-ideal, we use two methods, feedback mode and non-feedback mode, in terms of performance and overhead. It is proposed that the non-feedback mode is preferable even for some non-reciprocal channels. Principle analysis and test results are given. [ABSTRACT FROM AUTHOR]