Stephen Obono Ekwe

University of Cape Town | UCT · Department of Electrical Engineering

This paper investigates the utility maximization problem for cooperative users in the uplink of the 5G heterogeneous network. The paper considers the social ties between users who form communities on the network and the rationality behind their sharing of resources. Although there is a key assumption that users with social ties are viewed as being...

This paper examines the joint uplink and downlink energy consumption of current day wireless networks operating in the gigahertz spectrum while supporting a variety of wireless access devices, and propose a socially-inspired energy-efficient resource allocation algorithm for the future wireless network. First, the problem is conceptualized, modelle...

The 5G slice networks will play a critical role in meeting the stringent quality-of-service requirements of different use cases, reducing the Capital Expenditure (CapEX) and Operational Expenditure (OpEX) of mobile network operators. Owing to the flexibility and ability of 5G slice networks to meet the needs of different verticals, it attracts new...

Handbook of Whale Optimization Algorithm: Variants, Hybrids, Improvements, and Applications provides the most in-depth look at an emerging meta-heuristic that has been widely used in both science and industry. Whale Optimization Algorithm has been cited more than 5000 times in Google Scholar, thus solving optimization problems using this algorithm...

Handbook of Whale Optimization Algorithm: Variants, Improvements, Hydrids, and Applications

In this study, the specific absorption rate (SAR) and exposure index (EI) of access points (APs) and user equipment (UEs) in fourth-generation (4G) and fifth-generation (5G) wireless technologies are examined with regard to the effects of exposure to radiofrequency (RF) electromagnetic fields (EMF) radiation and the implications of their reduction....

Machine-type communication (MTC) plays a crucial role in the success of the internet of things (IoT) paradigm. It enables MTC devices (MTCDs) to communicate with each other seamlessly and efficiently, leading to improved automation, productivity, and user experience. However, the massive connections of these devices across cellular networks cause c...

Owing to the no free lunch theorem, no single optimisation algorithm can solve all optimisation problems accurately, so new optimisation techniques are required. In this paper, a novel metaheuristic called the deep sleep optimiser (DSO) is proposed. The deep sleep optimiser mimics the sleeping patterns of humans to solve optimisation problems. The...

This paper investigates the combined uplink and downlink energy efficiency via optimal user association for sum-rate maximization in an interference-based channel for current wireless networks operating in the gigahertz/terahertz spectrum while supporting a variety of wireless access devices and proposes an energy-efficient resource allocation algo...

This paper examines and employs the application of optical communication in solving physics-inspired engineering problem and periodic structure in plasmonics and photonics with inspired electromagnetic waves. The optical properties of the material (gold) such as dielectric function are employed and modelled i.e., the frequency-dependent dielectric...

Electron surface dissipation and quantum-limited size tend to control the material properties of exterior plasmon oscillation as the size of metal nanoparticles goes into the nanoscale domain. The need to examine this characteristic behaviour and its potential becomes imperative. This study explores the effects of the damping constant of electrons...

This paper describes and investigates the physics-based modelling of frequency-dependent dielectric function for small-scale device in optical communication system. Here, the study aims to examine the behaviour of material with low frequency-dependent permittivity with a view to unravelling the forms with metals such as noble (Ag, Au, Cu), Al, Be a...

This paper examines and employs the application of optical communication in solving physics-inspired engineering problem and periodic structure in plasmonics and photonics with inspired electromagnetic waves. The optical properties of the material (gold) such as dielectric function are employed and modelled i.e., the frequency-dependent dielectric...

The 5G mobile networks are required to meet the ever-increasing user demands. However, the rise in the user density accompanied by diverse user requirements places a heavy burden on the existing multiple access techniques, their complexity, and the tractability of mobile networks. Consequently , this leads to the optimum system capacity problem fac...

Schrödinger equation (SE) can be cast in differential form. For solving real problems, the differential equation needs to be discretised and solved numerically. Although the standard finite difference method (SFDM) is relatively straightforward to implement, both the boundary element method (BEM) and finite element method (FEM) are more tractable i...

This paper presents a Q-learning resource allocation scheme for spectrum re-use in a 5G communications network. The scheme aims to maximise the quality of experience (QoE) of users using reinforcement learning techniques. It exploits the social similarities of users to enable coexistence between primary and secondary user equipments on the same fre...

The extraordinary increase in size of wireless data traffic has championed the exploration of appropriate era in the radio spectrum chart to fulfil users ever-increasing demands and permit the utilisation of huge capacity and gargantuan connectivity. Hence, judging by this current radio allocation bandwidth, it is practically impossible to achieve...

The extraordinary increase in size of wireless data traffic has championed the exploration of appropriate era in the radio spectrum chart to fulfil users ever-increasing demands and permit the utilisation of huge capacity and gargantuan connectivity. Hence, judging by this current radio allocation bandwidth, it is practically impossible to achieve...

This paper investigates the utility maximization problem for cooperative users in the uplink of the 5G heterogeneous network. The paper considers the social ties between users who form communities on the network and the rationality behind their sharing of resources. Although there is a key assumption that users with social ties are viewed as being...

Due to the proliferation of user-specific applications, the use of additional spectrum in the fifth-generation (5G) wireless network will become inevitable. Although 5G promises the support of user-centric communications, there are still a number of technical challenges that need to be addressed. One such challenge is the association of user equipm...

The recent increase in variety for wireless smart devices and its corresponding applications can be directly related to the increase in data traffic today. This level of generated traffic is of growing concern to network operators who struggle to provide network resources to users of such saturated networks. In this paper, we consider a social comm...

The present study investigated energies of alpha-particles emitted by the triple-alpha sources (239Pu, 241Am and 244Cm) in a vacuum and measure the alpha particle properties at different pressures. The absolute activities for the radioisotopes in the triple alpha source (239Pu, 241Am and 244Cm) were found to be 678·25±26·0s-1,631·97±25·1s-1 and 146...