5G Mobile Communication Networks Research Articles

Nonorthogonal Random Access for 5G Mobile Communication Systems

This correspondence paper proposes two nonorthogonal random access (NORA) techniques for 5G mobile communication networks, where user equipments (UEs) make use of the channel inversion technique such that their received power at the base station (BS) can be one of the two target values. It enables the BS to decode two packets simultaneously with the successive interference cancellation (SIC) technique if a different power level is chosen. We propose two NORA systems; that is, UEs choose one of the two target power levels based on the channel gain or the region where they are. The performance of the proposed systems is analyzed in terms of access delay, throughput, and energy efficiency. Through analysis and extensive computer simulations, we show that the maximum throughput of the proposed NORA techniques can exceed 0.7, which is a significant improvement compared to the maximum throughput of conventional random access 0.368.

Toward Human-in-the-Loop Mobile Networks: A Radio Resource Allocation Perspective on Haptic Communications

The exchange of haptic information in remote operation systems allows humans to physically interact in remote environments with complete immersion. Such human-in-the-loop networks have been realized through wired solutions in the past. It is expected that the emerging 5G mobile communications networks will be able to meet the stringent requirements of real-time haptic interaction. By enabling haptic communications over 5G networks, human-in-the-loop mobile networks will emerge, that will support unprecedented applications. The main objective of this paper is to investigate the problem of radio resource allocation for haptic communications over 5G networks. The key requirements of haptic communications from a radio resource allocation perspective have been identified. These requirements have been translated into two distinct optimization problems for radio resource allocation, pertaining to perceptual coding and symmetric design cases. To reduce complexity, a two-step solution has been provided after decomposing the original optimization problems. In both cases, low-complexity greedy heuristic algorithms and near-optimal solutions have been proposed for resource allocation. Performance evaluation has been conducted based on a 5G air-interface design.

Optimized relaying and scheduling in cooperative Free Space Optical fronthaul/backhaul of 5G

The anticipated explosive growth of various Small Cells (SCs) urges the design of a high-rate, reliable and resource-efficient fronthaul/backhaul framework in the forthcoming fifth-generation (5G) mobile communication network, which has been attracting ever-increasing attentions and becoming a research hotspot. Motivated by the advances in Free Space Optical (FSO) and the growing interests in 5G, this paper investigates the feasibility of a 5G fronthaul/backhaul framework based on FSO communication system. We consider a Decode-and-Forward (DF) cooperative FSO relay system, aiming at maximizing system throughput. In contrast to traditional fronthaul/backhaul framework with fixed connections, we propose a dynamic fronthaul/backhaul framework using a relay selection algorithm to adapt different weather conditions and employ the back-pressure theory to boost transmission quality. Then, a link scheduling algorithm is further put forward to increase the resource utilization by making the most of the idle FSO links. Simulation results demonstrate that the cooperative FSO fronthaul/backhaul system based on the proposed algorithms can significantly improve the network performance in reliability and resource utilization, especially for data-intensive transmission.

Synthesis of multi‐polarised upside conical frustum array antenna for 5G mm‐Wave base station at 28/38 GHz

In this study, a multi-polarised millimetre-wave (mm-Wave) base station operating at 28/38 GHz is introduced for future fifth generation (5G) mobile communication networks. The proposed station employs 32-element array antenna distributed in upside conical frustum configuration (UCFC) to synthesise multi-beam patterns adopting directivity and polarisation control. First, the design of dual-band circularly polarised antenna element at 28/38 GHz is discussed. The measured results show that the designed antenna element has a reflection coefficient less than -23 dB with a realised antenna gain of 8 dBi, on average, in the assigned frequency bands. Based on the designed antenna element, the antenna array performance is studied in terms of gain, radiation efficiency, reflection coefficient, and coverage efficiency. The results are compared with those obtained from 32-element structured in an octagonal prism configuration (OPC). For antenna design parameters and multi-beam pattern synthesis, a modified version of hybrid gravitational search algorithm and particle swarm optimisation is proposed. It is found that, the introduced UCFC outperformed the OPC by 19.8%. Moreover, distributing the antenna array in UCFC improved the convergence by 21.7% compared to OPC.

Energy-Efficient Resource Allocation in NOMA Heterogeneous Networks

Non-orthogonal multiple access (NOMA) has attracted much recent attention owing to its capability for improving the system spectral efficiency in wireless communications. Deploying NOMA in heterogeneous network can satisfy users' explosive data traffic requirements, and NOMA will likely play an important role in the fifth-generation (5G) mobile communication networks. However, NOMA brings new technical challenges on resource allocation due to the mutual cross-tier interference in heterogeneous networks. In this article, to study the tradeoff between data rate performance and energy consumption in NOMA, we examine the problem of energy-efficient user scheduling and power optimization in 5G NOMA heterogeneous networks. The energy-efficient user scheduling and power allocation schemes are introduced for the downlink 5G NOMA heterogeneous network for perfect and imperfect channel state information (CSI) respectively. Simulation results show that the resource allocation schemes can significantly increase the energy efficiency of 5G NOMA heterogeneous network for both cases of perfect CSI and imperfect CSI.

Design and Simulation of a New Intelligent Authentication for Handover over 4G (LTE) Mobile Communication Network

LTE has become the dominant mobile communication network as it provides higher data rate, higher level of security and more applicable services. The handover is a critical process as it needs to be rapid and accurate process. In the handover over the Long Term Evolution (LTE) standard security protocol, the key management takes place between the source eNodeB and target eNodeB under the Mobility Management Entity (MME) via X2 interface. 3GPP has specified some security mechanisms to ensure the safety of handover key management, but still there exist some vulnerabilities compromising the security of the handover process, such as desynchronization attack. This paper proposed a new Lightweight Intelligent authentication protocol, which solves the desynchronization attack, solves Man in The Middle Attack, and achieves shorter setup time. This protocol solves the desynchronization attack and Man in The MiddleAttack by adding a Certificate Authority (CA), which generates a certificate for each eNB of the LTE network. In addition, the proposed protocol achieves shorter setup time by applying a parallel key management and handover instead of sequential key management and handover with each eNB. The proposed protocol assumes a new method of authentication of the User Equipment (UE) by using a Key Management Unit (KMU).The proposed protocol is securely analyzed. In addition, measuring the performance analysis in terms of the communication overhead, computations overhead and setup time by using Eclipse Real Time Operating System program. Finally, the proposed protocol is compared with the Standard protocol and MRN related work.

IEEE Access Special Section Editorial: High Mobility 5G LTE-V: Challenges and Solutions

The Internet of Vehicles, previously referred to as Vehicular Ad Hoc Networks (VANETs), will be a collection of mobile ad hoc networks for vehicular communications to improve driving safety and traffic efficiency. Major categories include vehicle-to-vehicle (V2V) communications and vehicle-to-infrastructure (V2I) communications. Collectively these (and future categories) can be termed V2X communications. These two categories entail a variety of communication channels, network topologies, vehicle densities and communication scenarios, and in response to this, IEEE has released the IEEE 802.11p and IEEE 1609 protocols for VANETs. With the global commercial application of Long Term Evolution (LTE) mobile communication systems, LTE based vehicular (LTE-V) networks have been shown to offer advantages in V2I communications, coverage, high mobility and complicated communication scenarios. Therefore, in the 5th generation’s (5G) mobile communication networks, the 3GPP is discussing V2V communications as a device-to-device (D2D) communication application. As is well known, in high mobility scenarios, the wireless channel is rapidly time- varying, Doppler shifts and spreads can be much larger than in cellular, network topology can change quickly, and switching among base stations and vehicles is more frequent. All this presents formidable challenges to realizing reliable communications with low latency in 5G LTE-V systems.

5G Mobile Communication Development Trend and Several Key Technologies

The overall performance of 5G mobile communication network has made great progress compared with 4G network. In order to ensure the expected utility of 5G communication system in practical application, this paper will focus on the future development trend of this communication system and its research on key technologies involved in the application process to provide theoretical support to relevant practitioners.

Research on wireless coverage area detection technology for 5G mobile communication networks

In the field of 5G mobile communication networks, coverage performance is an important indicator that can affect the user’s terminal experience. The current method for coverage detection is drive test, which is based on mobile terminals. Although the application of the technology in practice has matured, the implementation of drive test requires additional time and manpower. However, in the test phase of a 5G mobile communication network, the detection should be on-the-spot, real time, and repeatable. To overcome these challenges, this article proposes 5G network wireless coverage area detection technology that is based on wireless sensor networks. First, sensor nodes are deployed to collect the received signal strength. Second, the algorithm performs Gaussian filtering on collected data. Then, an interpolation estimation algorithm is adopted to estimate the interpolation of the area. Finally, the data collected by sensor nodes and estimated by interpolation points are integrated to generate the effective...

Sustainable Green Networking and Computing in 5G Systems

The articles in this special section focus on the design of 5G mobile communication networks that deploy the development of green and sustainable networking and computing protocols.

5G green mobile communication networks

With the popularization of wireless multimedia communications, the wireless traffic is predicated to be increased more than 1000 time in the next decade. Some new technologies, e.g., massive multi-input multi-output antennas, millimeter wave and small cell networks are developed to support high speed wireless transmission in future fifth generation (5G) mobile communication systems. On the other hand, it is a great challenge how to face the quick growth of energy consumption in 5G mobile communication networks due to the massive wireless traffic. However, detailed investigation of the energy efficiency of 5G mobile communication networks from three aspects of theory models, technology developments and applications is surprisingly rare in the open literature. Fortunately, the scholarly writing, 5G Green mobile communication networks, published by Publishing House of Electronics Industry in November 2016, points out the directions and research advance of 5G green mobile communication networks.

Performance Analysis of Nonorthogonal Multiple Access for Relaying Networks Over Nakagami-<inline-formula> <tex-math notation="LaTeX">$m$</tex-math> </inline-formula> Fading Channels

Nonorthogonal multiple access (NOMA), which can improve the spectrum efficiency and system throughput compared with conventional orthogonal multiple access (OMA), has been regarded as a promising technique for the fifth-generation (5G) mobile communication network. In this paper, we consider a NOMA-based relaying networks over Nakagami- $m$ fading channels, where the base station communicates with multiple mobile users simultaneously through the help of an amplify-and-forward (AF) relay. First, we study the system outage behavior, and closed-form expressions for the exact outage probability and simple bounds of the outage probability are obtained, respectively. The analytical results are further evaluated in the high-signal-to-noise-ratio (SNR) regime to explicitly characterize the diversity order of the network. Next, the ergodic sum rate achieved by the network is investigated, and expressions for the lower and upper bounds of the ergodic sum rate are derived. Finally, numerical examples are conducted to confirm the validity of our analysis and show a comparison of NOMA against conventional OMA networks. NOMA is reported to outperform conventional OMA and provide better spectral efficiency and user fairness.

Novel Opportunistic Network Routing Based on Social Rank for Device-to-Device Communication

In recent years, there has been dramatic proliferation of research concerned with fifth-generation (5G) mobile communication networks, among which device-to-device (D2D) communication is one of the key technologies. Due to the intermittent connection of nodes, the D2D network topology may be disconnected frequently, which will lead to failure in transmission of large data files. In opportunistic networks, in case of encountering nodes which never meet before a flood message blindly to cause tremendous network overhead, a novel opportunistic network routing protocol based on social rank and intermeeting time (SRIT) is proposed in this paper. An improved utility approach applied in utility replication based on encounter durations and intermeeting time is put forward to enhance the routing efficiency. Meanwhile, in order to select better candidate nodes in the network, a social graph among people is established when they socially relate to each other in social rank replication. The results under the scenario show an advantage of the proposed opportunistic network routing based on social rank and intermeeting time (SRIT) over the compared algorithms in terms of delivery ratio, average delivery latency, and overhead ratio.

Seven fundamental rethinking for next-generation wireless communications

The fifth-generation (5G) mobile communication networks, which are anticipated to be soft, green, and super-fast, may possibly be deployed in 2020s to satisfy the challenging demands of mobile communication in various scenarios. Characterized by a mixed set of key performance indicators like data rates, latency, mobility, energy efficiency, and traffic density, 5G services demand a fundamental revolution on the end to end network architecture and key technologies design. Toward a “soft, green, and super-fast” 5G, this paper presents seven innovative 5G R&D themes of China Mobile, including: (1) rethinking Shannon to start a green journey on wireless systems; (2) rethinking Ring and Young for no more “cells”; (3) rethinking signaling and control to make network applications aware and load aware; (4) rethinking antennas to make base stations invisible via SmarTiles; (5) rethinking spectrum and air interface to enable wireless signals to “dress for the occasion”; (6) rethinking fronthaul (FH) to enable Soft RAN via next-generation FH interface; and (7) rethinking the protocol stack for flexible configurations of diversified access points and optimal baseband function split between the base band unit pool and the Remote Radio Systems.

Millimetre-Wave Backhaul for 5G Networks: Challenges and Solutions.

The trend for dense deployment in future 5G mobile communication networks makes current wired backhaul infeasible owing to the high cost. Millimetre-wave (mm-wave) communication, a promising technique with the capability of providing a multi-gigabit transmission rate, offers a flexible and cost-effective candidate for 5G backhauling. By exploiting highly directional antennas, it becomes practical to cope with explosive traffic demands and to deal with interference problems. Several advancements in physical layer technology, such as hybrid beamforming and full duplexing, bring new challenges and opportunities for mm-wave backhaul. This article introduces a design framework for 5G mm-wave backhaul, including routing, spatial reuse scheduling and physical layer techniques. The associated optimization model, open problems and potential solutions are discussed to fully exploit the throughput gain of the backhaul network. Extensive simulations are conducted to verify the potential benefits of the proposed method for the 5G mm-wave backhaul design.

5G roadmap: 10 key enabling technologies

The fifth generation (5G) mobile communication networks will require a major paradigm shift to satisfy the increasing demand for higher data rates, lower network latencies, better energy efficiency, and reliable ubiquitous connectivity. With prediction of the advent of 5G systems in the near future, many efforts and revolutionary ideas have been proposed and explored around the world. The major technological breakthroughs that will bring renaissance to wireless communication networks include (1) a wireless software-defined network, (2) network function virtualization, (3) millimeter wave spectrum, (4) massive MIMO, (5) network ultra-densification, (6) big data and mobile cloud computing, (7) scalable Internet of Things, (8) device-to-device connectivity with high mobility, (9) green communications, and (10) new radio access techniques. In this paper, the state-of-the-art and the potentials of these ten enabling technologies are extensively surveyed. Furthermore, the challenges and limitations for each technology are treated in depth, while the possible solutions are highlighted.

Proposed Technologies for Solving Future 5G Heterogeneous Networks Challenges

The evolution towards 5G mobile communication networks will be characterized by increasing number of wireless devices and service complexity, while the requirement to access mobile services will be essential. This paper presents an overview of the evolution of wireless networks, and focus on future mobile communication generation (5G) with its requirements, Challenges and Services. In addition, we propose a HetNet based architecture for 5G networks. The key ideas for each of the technologies are stated, along with the potential impact on 5G networks architecture.The proposed HetNet architecture key elements such as Small cells, Massive MIMO, mm-waves, D2D communication, full-duplex communication, energy harvesting, Cloud-RAN and Wireless Network Virtualization, all of these technologies serve together to ensure users with Quality of service (QoS) requirement in a spectrum & energy efficient manner. Keywords: 5G networks, wireless cellular networks, 5G networks, 5G heterogeneous network architecture, small cells, D2D communications, Massive MIMO, mm-wave, C-RAN, energy harvesting.

Cooperative interference mitigation and handover management for heterogeneous cloud small cell networks

Heterogeneous small cell network has attracted much attention to satisfy users' explosive data traffic requirements. Heterogeneous cloud small cell network (HCSNet), which combines cloud computing and heterogeneous small cell network, will likely play an important role in 5G mobile communication networks. However, with massive deployment of small cells, co-channel interference and handover management are two important problems in HCSNet, especially for cell edge users. In this article, we examine the problems of cooperative interference mitigation and handover management in HCSNet. A network architecture is described to combine cloud radio access network with small cells. An effective coordinated multi-point (CoMP) clustering scheme using affinity propagation is adopted to mitigate cell edge users' interference. A low complexity handover management scheme is presented, and its signaling procedure is analyzed in HCSNet. Numerical results show that the proposed network architecture, CoMP clustering scheme and handover management scheme can significantly increase the capacity of HCSNet while maintaining users' quality of service.

5G: The Convergence of Wireless Communications.

As the rollout of 4G mobile communication networks takes place, representatives of industry and academia have started to look into the technological developments toward the next generation (5G). Several research projects involving key international mobile network operators, infrastructure manufacturers, and academic institutions, have been launched recently to set the technological foundations of 5G. However, the architecture of future 5G systems, their performance, and mobile services to be provided have not been clearly defined. In this paper, we put forth the vision for 5G as the convergence of evolved versions of current cellular networks with other complementary radio access technologies. Therefore, 5G may not be a single radio access interface but rather a “network of networks”. Evidently, the seamless integration of a variety of air interfaces, protocols, and frequency bands, requires paradigm shifts in the way networks cooperate and complement each other to deliver data rates of several Gigabits per second with end-to-end latency of a few milliseconds. We provide an overview of the key radio technologies that will play a key role in the realization of this vision for the next generation of mobile communication networks. We also introduce some of the research challenges that need to be addressed.

Power Level Distributions of Radio Base Station Equipment and User Devices in a 3G Mobile Communication Network in India and the Impact on Assessments of Realistic RF EMF Exposure

The aim of this paper is to present results on output power level distributions of radio base stations (RBSs) and user devices connected to a wideband code division multiple access-based third generation (3G) mobile communication network in India and relate the results to realistic human exposure to radio frequency (RF) electromagnetic field (EMF) emitted by the corresponding RBSs and the devices. The output power level distributions have been obtained through network-based measurements. In downlink, data from 868 RBSs were gathered during seven days. The RBSs were connected to five different radio network controllers (RNCs) located in different regions of India. The mean, the median, and the 95th percentile RBS output power values were found to be 24%, 21%, and 53%, respectively, of the maximum available power. In the uplink direction, output power levels of 3G devices connected to 1256 RBSs and the same five RNCs as in the downlink were assessed separately for voice, data, voice + data, and video applications. In total, more than 1 million hours of data traffic and more than 700 000 h of voice calls were measured in the uplink. The mean output power for the voice, data, the voice + data, and the video were found to be around 1%, 3%, 2%, and 4%, respectively, of the maximum available power for the 3G user devices. The findings are in line with previously published results obtained in other networks in Europe, and demonstrate that knowledge on realistic power levels is important for accurate assessments of the RF EMF exposure.