Current Issue : April - June Volume : 2020 Issue Number : 2 Articles : 5 Articles
Non-orthogonal multiple access (NOMA) has become the key technology in the future\n5G wireless networks. It can achieve multi-user multiplexing in the transmit power domain by\nallocating different power, which can effectively improve the system capacity and spectral\nefficiency. Aiming at the problem of high computational complexity and improving system\ncapacity in non-orthogonal multiple access (NOMA) based on orthogonal frequency division\nmultiple access (OFDMA) for 5G wireless cellular networks, this paper proposes an improved low\ncomplexity radio resource allocation algorithm for user grouping and power allocation\noptimization. The optimization model is established with the goal of maximizing system capacity.\nThrough the step-by-step optimization idea, the complex non-convex optimization problem is\ndecomposed into two sub-problems to be solved separately. Firstly, all users are grouped based on\nthe greedy method, and then the power allocation is performed on the sub-carriers of the fixed\ngroup. Simulation results show that the proposed algorithm has better system capacity than the\nexisting state-of-the-art algorithms and reduced complexity performance....
Mobile edge computing (MEC) is considered a promising technique that prolongs battery life and enhances the computation\ncapacity of mobile devices (MDs) by offloading computation-intensive tasks to the resource-rich cloud located at the edges of\nmobile networks. In this study, the problem of energy-efficient computation offloading with guaranteed performance in multiuser\nMEC systems was investigated. Given that MDs typically seek lower energy consumption and improve the performance of\ncomputing tasks, we provide an energy-efficient computation offloading and transmit power allocation scheme that reduces\nenergy consumption and completion time. We formulate the energy efficiency cost minimization problem, which satisfies the\ncompletion time deadline constraint of MDs in an MEC system. In addition, the corresponding Karushâ??Kuhnâ??Tucker conditions\nare applied to solve the optimization problem, and a new algorithm comprising the computation offloading policy and\ntransmission power allocation is presented. Numerical results demonstrate that our proposed scheme, with the optimal\ncomputation offloading policy and adapted transmission power for MDs, outperforms local computing and full offloading\nmethods in terms of energy consumption and completion delay. Consequently, our proposed system could help overcome the\nrestrictions on computation resources and battery life of mobile devices to meet the requirements of new applications....
With the increasing demand for data traffic and with the massive foreseen\ndeployment of the Internet of Things (IoT), higher data rates and capacity are\nrequired in mobile networks. While Heterogeneous Networks (HetNets) are\nunder study toward 5G technology, Wireless Fidelity (WiFi) Access Points\n(APs) are considered a potential layer within those multiple Radio Access\nTechnologies (RATs). For this purpose, we have proposed in this paper a\nnovel WiFi dimensioning method, to offload data traffic from Long Term\nEvolution (LTE) to WiFi, by transferring the LTE energy consuming heavy\nusers, to the WiFi network. First, we have calculated the remaining available\ncapacity of the WiFi network based on the estimated load of each WiFi physical\nchannel using the overlapping characteristic of the channels. Then, we\nwere able through this dimensioning method, to calculate the minimum\nneeded number of WiFi APs that ensure the same or better throughput for\nthe LTE transferred users. By this method, we have ensured additional capacity\nin the LTE network with minimum investment cost in the WiFi network.\nFinally, we have estimated the profit sharing between LTE and WiFi by considering\ndata bundles subscription revenues and the infrastructure capital and\noperational costs. We have calculated for each network the profit share using\na coalition game theory Shapley value that pinpoints the benefit of the cooperation\nusing the proposed dimensioning method....
Advances in mobile phone technology and the growth of associated networks have been phenomenal over the last decade.\nTherefore, they have been the focus of much academic research, driven by commercial and end-user demands for increasingly\nfaster technology. Themost recent generation of mobile network technology is the fifth generation (5G). 5G networks are expected\nto launch across the world by 2020 and to work with existing 3G and 4G technologies to provide extreme speed despite being\nlimited to wireless technologies. An alternative network, Y-Communication (Y-Comm), proposes to integrate the current wired\nand wireless networks, attempting to achieve the main service requirements of 5G by converging the existing networks and\nproviding an improved service anywhere at any time. Quality of service (QoS), vertical handover, and security are some of the\ntechnical concerns resulting from this heterogeneity. In addition, it is believed that the Y-Comm convergence will have a greater\ninfluence on security than was the case with the previous long-term evolution (LTE) 4G networks and with future 5G networks.\nThe purpose of this research is to satisfy the security recommendations for 5G mobile networks. This research provides a policybased\nsecurity management system, ensuring that end-user devices cannot be used as weapons or tools of attack, for example, IP\nspoofing and man-in-the-middle (MITM) attacks.Theresults are promising, with a low disconnection rate of less than 4% and 7%.\nThis shows the system to be robust and reliable....
The issue of spectrum scarcity in wireless networks is becoming prominent and critical with each passing year. Although several\npromising solutions have been proposed to provide a solution to spectrum scarcity, most of them have many associated tradeoffs.\nIn this context, one of the emerging ideas relates to the utilization of cognitive radios (CR) for future heterogeneous networks\n(HetNets). This paper provides a marriage of two promising candidates (i.e., CR and HetNets) for beyond fifth generation (5G)\nwireless networks. More specifically, a joint power allocation and user assignment solution for the multiuser underlay CR-based\nHetNets has been proposed and evaluated. To counter the limiting factors in these networks, the individual power of transmitting\nnodes and interference temperature protection constraints of the primary networks have been considered. An efficient solution is\ndesigned from the dual decomposition approach, where the optimal user assignment is obtained for the optimized power allocation\nat each node. The simulation results validate the superiority of the proposed optimization scheme against conventional\nbaseline techniques....
Loading....