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The number of wireless connected devices are growing exponentially and the importance of this research area is growing as well to meet the known and looming challenges and expectations. The 5:th Generation telecommunications standard is partly embodied by the Machine-to-Machine (M2M) and Internet of Things (IoT) technologies and standards to handle a big part of these devices and connections. An example within the IoT paradigm is military training systems where each system can consist of thousands of battery operated mobile devices and their shifting requirements shall be fullled in an energy-aware manner to increase battery operating times. Military training radio networks enables realistic combat training. The services and features provided in commercial telecommunications networks are desirable in these often proprietary and task specic networks, increasing capabilities and functionalities. To facilitate the current and future R&D of LTE based networks for adoption in military training networks and services this doctoral thesis intends to provide the starting ground for the energy-aware LTE based wireless communications. The thesis first presents general solutions on how to meet traffic deadlines in wireless networks for large number of nodes, and then continues with solutions for energy-aware LTE-based communications for the User Equipments (UEs). The work builds on the problem formulation how to provide energy-aware resource handling for LTE-based military training networks from where three research questions are derived. From the research questions we derive different hypotheses and then test these within the investigated area to answer the research questions. The contributions of this work are within areas of resource handling and power saving for mobile devices. In the first area an admission control using deterministic analysis is proposed fullling traffic requirements for military training mobile nodes. This admission control is enhanced for multiple-channel base stations, and evaluated using ...

Connected devices are increasing steadily and the number of devices will in soon future be so massive that they are impacting the next generation of wireless standards and are already being considered in them. Machine-to-Machine (M2M) communications and Internet of Things (IoT) sub fields of wireless communications have developed lately with their own research fields and forums. Military training systems are using radio networks of connected devices to provide realistic combat training with new trends of multimedia streaming and lower traffic latency requirements. To facilitate further development of the networks a research goal is formulated to target the improvement of the network in the desired direction. The research goal is to answer how to provide energy efficient wireless communications within the framework of the military training application, meeting requirements of delay, number of network nodes and power efficiency for mobile devices and is broken down to three separate research questions that are each targeted separately as below. We have developed an admission control with real-time analysis for a single-frequency base station for mobile nodes with real-time traffic. This scope has been extended to an admission control for a multichannel base station where we also proposed a method on how to maximize the number of mobile nodes, with different traffic requirements including multimedia traffic, in the network. Finally a probabilistic model has been proposed for the Discontinuous Reception (DRX) power saving mechanism for LTE/LTE-A in the 4:th Generation (4G) telecommunications standard. It was also shown how to meet traffic delays while maximizing the power saving factor in the mobile nodes. ; Examiner: Professor Walid Taha, Halmstad University

LTE/LTE-A are emerging communication technologies on the way towards 5G telecommunication systems. Ubiquitous adoption of connectivity in between different kinds of sensors, wearable devices and other low-power equipment raises an importance of the energy-efficient wireless communications. In LTE/LTE-A the Discontinuous Reception Mechanism (DRX) aims at power saving of User Equipment (UE) devices. In the paper we present an analysis of DRX, which is novel in two dimensions. First, our analytical approach is different to existing ones due to the use of Markov chain instead of a semi-Markov ones. Secondly, along with the generic traffic models we also analyze the efficiency of DRX for military training application systems, what has not been done before. We suggest few practical recommendations regarding the DRX parameters tuning also. © 2015 IEEE.

A military training radio network requires support for a large number of mobile nodes with heterogeneous traffic and real-time requirements. We propose a deterministic protocol and an admission control using real-time analysis for a centralized radio network with a multichannel base station. The admission control implements an algorithm for frequency allocation to mobile nodes, and guarantees timely treatment of real-time traffic. The proposed online heuristic frequency allocation algorithm is compared to other known heuristic algorithms: round robin over channels and fill one channel first. The goal with the heuristic algorithms is to maximize the number of supported mobile nodes. Our results show that when the high utilization part of the traffic have shorter deadlines it is advantageous to differentiate different types of nodes onto separate frequencies, whilst if the deadline is increased it is advantageous to mix different types of nodes on each frequency. © Copyright 2015 IEEE