Handover (HO) is one of the key aspects of next-generation (NG) cellular communication networks that need to be properly managed since it poses multiple threats to quality-of-service (QoS) such as the reduction in the average throughput as well as service interruptions. With the introduction of new enablers for fifth-generation (5G) networks, such as millimetre wave (mm-wave) communications, network densification, Internet of things (IoT), etc., HO management is provisioned to be more challenging as the number of base stations (BSs) per unit area, and the number of connections has been dramatically rising. Considering the stringent requirements that have been newly released in the standards of 5G networks, the level of the challenge is multiplied. To this end, intelligent HO management schemes have been proposed and tested in the literature, paving the way for tackling these challenges more efficiently and effectively. In this survey, we aim at revealing the current status of cellular networks and discussing mobility and HO management in 5G alongside the general characteristics of 5G networks. We provide an extensive tutorial on HO management in 5G networks accompanied by a discussion on machine learning (ML) applications to HO management. A novel taxonomy in terms of the source of data to be utilized in training ML algorithms is produced, where two broad categories are considered; namely, visual data and network data. The state-of-the-art on ML-aided HO management in cellular networks under each category is extensively reviewed with the most recent studies, and the challenges, as well as future research directions, are detailed.

Wireless communication networks have been witnessing unprecedented demand due to the increasing number of connected devices and emerging bandwidth-hungry applications. Although there are many competent technologies for capacity enhancement purposes, such as millimeter wave communications and network densification, there is still room and need for further capacity enhancement in wireless communication networks, especially for the cases of unusual people gatherings, such as sport competitions, musical concerts, etc. Unmanned aerial vehicles (UAVs) have been identified as one of the promising options to enhance capacity due to their easy implementation, pop-up fashion operation, and cost-effective nature. The main idea is to deploy base stations on UAVs and operate them as flying base stations, thereby bringing additional capacity where it is needed. However, UAVs mostly have limited energy storage, hence, their energy consumption must be optimized to increase flight time. In this survey, we investigate different energy optimization techniques with a top-level classification in terms of the optimization algorithm employed—conventional and machine learning (ML). Such classification helps understand the state-of-the-art and the current trend in terms of methodology. In this regard, various optimization techniques are identified from the related literature, and they are presented under the above-mentioned classes of employed optimization methods. In addition, for the purpose of completeness, we include a brief tutorial on the optimization methods and power supply and charging mechanisms of UAVs. Moreover, novel concepts, such as reflective intelligent surfaces and landing spot optimization, are also covered to capture the latest trends in the literature.

Life on Earth depends on healthy oceans, which supply a large percentage of the planet’s oxygen, food, and energy. However, the oceans are under threat from climate change, which is devastating the marine ecosystem and the economic and social systems that depend on it. The Internet of Underwater Things (IoUT), a global interconnection of underwater objects, enables round-the-clock monitoring of the oceans. It provides high-resolution data for training machine learning (ML) algorithms for rapidly evaluating potential climate change solutions and speeding up decision making. The sensors in conventional IoUT are battery powered, which limits their lifetime, and constitutes environmental hazards when they die. In this article, we propose a sustainable scheme to improve the throughput and enable wireless charging of underwater networks, enabling them to potentially operate indefinitely. The scheme is based on simultaneous wireless information and power transfer (SWIPT) from an autonomous underwater vehicle (AUV) used for data collection. We model the problem of jointly maximizing throughput and harvested power as a Markov decision process (MDP), and develop a model-free reinforcement learning (RL) solution. The model’s reward function incentivises the AUV to find optimal trajectories that maximize throughput and power transfer to the underwater nodes while minimising its own energy consumption. To the best of our knowledge, this is the first attempt at using RL for this application. The scheme is implemented in an open 3-D RL environment specifically developed in MATLAB for this study. The performance results show up 207% improvement in energy efficiency compared to those of a random trajectory scheme used as a baseline model.

System's propagation characteristics through a medium is one of the important task to be done before planning and optimization of any network in order to estimate the signal parameter accurately for mobile system. Propagation analysis provides a good initial estimate of the signal characteristics .The ability to accurately predict radio-propagation behaviour for wireless personal communication system, such as cellular mobile radio, is becoming crucial to system design. This paper aim to address various propagation model used in planning and optimization of the network and much emphasize on empirical (statistical) models it address models limitation and its applicability. To validate the models, field measurements were carried out at different locations within Dar es Salaam and its environs. The measurements system consist of live radio base stations transmitting at 900/ 1800/2100 MHz Downlink signal strength level data were collected using drive test exercise. The respective path loss values were estimated and compared with existing model for rural, suburban and urban areas. The result indicated an appreciable inconsistency with the empirical models for all terrain areas.

5G spectral efficiency requirements foresee network densification as a potential solution to improve capacity and throughput to target next-generation wireless networks (NGWNs). This is achieved by shrinking the footprint of base stations (BSs), effective frequency reuse, and dynamic use of shared resources between users. However, such a deployment results in unnecessary handovers (HOs) due to the cell size decrements, and limited sojourn time on a high train mobility. In particular, when a train speedily passes through the BS radio coverage footprints, frequent HO rate may result in serious communication interruption impacting quality of service (QoS). This paper proposes a novel context-aware HO skipping that relies on passenger mobility, trains trajectory, travelling time and frequency, network load and signal to interference and noise ratio (SINR) data. We have modelled passenger traffic flows in cardinal directions i.e, north, east, west, and south (NEWS), in a novel framework that employs realistic Poisson point process (PPP) for real-time mobility patterns to support mobile networks. Spatio-temporal simulations leveraging NEWS mobility prediction model with machine learning (ML) where support vector machine (SVM) shows an accuracy of 94.51%. ML-driven mobility prediction results integrate into our proposed scheme that shows comparable coverage probability, and average throughput to the no skipping case, while significantly reducing HO costs.