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Conventional wireless techniques are becoming inadequate for beyond fifth-generation (5G) networks due to latency and bandwidth considerations. To increase the wireless network throughput and improve wireless communication systems’ error performance, we propose physical layer network coding (PNC) in an Intelligent Reflecting Surface (IRS)-assisted environment. We consider an IRS-aided butterfly network, where we propose an algorithm for obtaining the optimal IRS phases. Also, analytic expressions for the bit error rate (BER) are derived. The numerical results demonstrate that the scheme proposed in this thesis significantly enhances the BER performance. The proposed scheme is compared to traditional network coding without IRS. For instance, at a target BER of 10−3, 28 dB and 0.75 dB signal to noise ratio (SNR) gains are achieved at the relay and destination node of the 32-element IRS-assisted butterfly network model.

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The purpose of this study was to understand how female amateur (college) developmental level football players perceived and responded to video-based feedback sessions during their athletic training and competition. A purposeful sample was used to select 5 participants. 2 research questions were asked to explore how 5 different formats of video-based feedback sessions influenced the participants during the coaching process. The researcher was the instrument used for collecting data and this included semi-structured interviews, participant observation and a journal (personal document). Replication logic was utilized for the multiple case study research design. The trustworthiness of the study was enhanced using prolonged engagement in the field, thick description, triangulation, purposeful sampling, field notes and a reflexive journal. A cross-case analysis of the data revealed 3 major themes. These were: (a) learning, (b) motivation, and (c) barriers to implementing coaching points. The findings for theme 1 revealed the participants learned from receiving video-based feedback sessions by being prepared tactically through oppositional analysis reviews, understanding the teams playing style and/or their roles and responsibilities within it, accurately identifying personal and team areas for improvement, learning coaching points, increasing their attention to and retention of coaching points and seeing an accurate account of their performance which had contradicted what they thought during or following a performance. The findings for theme 2 revealed viewing past individual/team successes and other sports teams’ successes had a motivational and positive psychological effect on the participants. Also, the participants were motivated to increase their effort and intensity levels when receiving video-based feedback and stated video reviews should balance positive and negative clips to protect their confidence, self-esteem and motivation. The findings for theme 3 revealed three barriers to the learning and subsequent implementation of coaching points in the coaching process. These were ineffective training sessions, life as an intercollegiate student-athlete and the psychological factors of cognitive anxiety and low self-efficacy. Recommendations included further qualitative studies to track the nuances behind memory retention and the role self-efficacy and other psychological factors play during the learning of coaching points received from video-based feedback sessions at the developmental level of football.

Reconfigurable intelligent surfaces (RISs) are now considered among the key enabling technologies catering to the ever-increasing demand for traffic rate in the future fifth-generation beyond or even sixth-generation. RISs can be leveraged to transform the propagation environment into a smart space that can be programmable for the benefit of the communication application. Throughout this proposal, we study RIS-assisted systems from different perspectives to analyze and enhance the operation of such systems in different setups. In this context, we first analyze the performance of the RIS-assisted single-input single-output (SISO) system and make a fair comparison with the conventional relaying system. Then, we investigates the use of a RIS to aid point-to-point multi-data-stream multiple-input multiple-output (MIMO) wireless communications. With practical finite alphabet input, the reflecting elements at the RIS and the precoder at the transmitter are alternatively optimized to minimize the symbol error rate. Considering the same RIS-assisted MIMO system, We further explore the potential of RIS for acting as an active modulator and piggybacking its own information when helping the information transmission between the transmitter and the receiver at the same time. Furthermore, considering a RIS-assisted SISO system over the millimeter wave channel, we propose an appropriate design of the phase shifts of each element at the RIS so as to maximize the received signal power at the desired user, while nulling the received interference signal power at the undesired user. However, most of the works investigated the use of continuous phase shift designs, which cannot be implemented in practice. It motivates us to investigate the control of the phases shifts under the assumption that they belong to a finite discrete set. As the above-mentioned performance analysis and optimization of RIS-assisted system requires the channel state information, we thus address the channel estimation problem for a point-to-point SISO system and a point-to-point multiple-input single-output system, respectively. Finally, we highlight some possible future research directions to be considered for the thesis.

Offloading tasks to a network processor is one of the important ways to increase server performance. Hardware offloading of Transmission Control Protocol/Internet Protocol (TCP/IP) intensive tasks is known to significantly improve performance. When the entire application is considered for offloading, the impact on the server can be significant because it significantly reduces the load on the server. The goal of this thesis is to consider such a system with application-level offloading, rather than hardware offloading, and gauge its performance benefits. I am implementing this project on an Apache httpd server (running RedHat Linux), on a system that utilizes a co-located network processor system (IXP2855). The performance of the two implementations is measured using the SPECweb2005 benchmark, which is the accepted industry standard for evaluating Web server performance.

Satellite communication (SatCom) is an essential component of next-generation wireless communications. The existing terrestrial network will be overwhelmed due to the rapid growth of demand for data and serving remote areas by using only terrestrial networks is demanding. In addition, terrestrial communications are susceptible to natural disasters such as earthquakes and floods. In order to overcome these disadvantages of the terrestrial communication systems, SatCom systems are being deployed and covering remote or sparsely populated areas. However, research on SatCom is still not enough and it has not been studied as much as on terrestrial communication. In this thesis, we investigate and analyze system models using SatCom. Furthermore, we present to improve the performance of SatCom by applying the proposed techniques in terrestrial communications. First of all, we analyze the outage probability and symbol error rate of the SatCom system. In single-beam and multi-beam situations, all factors that can be considered in the SatCom channel model are considered. Since the beam coverage of the satellite is broad, a number of users are randomly distributed within the beam. We investigate the performance of the SatCom system according to the user selection methods considering the user's location as well. Secondly, a system in which multiple gateways transmit signals over multiple beams is taken into account. Many users are placed in each beam, and inter-beam interference exists due to full-frequency reuse. To simultaneously cover the multiple users in the beam, signals are transmitted using non-orthogonal multiple access. In order to maximize system throughput, precoding for interference mitigation and NOMA optimization techniques are proposed. Finally, a cognitive radio network in which high-altitude platforms (HAPs) are applied to conventional SatCom systems and share frequency bands with SatCom is taken into consideration. HAPs are used to cover user-dense areas within satellite beam coverage. In order to properly handle interference caused by spectrum sharing and improve the system data rate, precoding and frequency band allocation schemes are proposed.

The purpose of this study was to evaluate a family camp's performance from a consumer (parent) perspective. An Importance-Performance Analysis was used. Responses averages were plotted on a grid of importance versus performance with the overall means used as cross-hairs to create an action grid of four quadrants: keep-up-the-good-work (high importance/high performance), concentrate-here (high importance/low performance), possible-overkill (low importance/high performance), and low-priority (low importance/low performance). Findings indicated that parents are in large part receiving good performance on the factors that are important to them. Findings identified factors that were important to parents including some factors that camp directors were not previously aware of. Three of the five highest importance factor scores were regarding accommodations (clean facility, restrooms provided, and showers provided). All five of the top performance factor scores were regarding programming details. Implications for family camp providers and recommendations for future research are discussed.

To address the various emerging standards like BluetoothTM, Home RF, Wi-fiTM (IEEE 802.11), ZigBeeTM etc., in the field of wireless communications, different transceivers have been designed to operate at various frequencies such as 450 MHz, 902-920 MHz, 2.4 GHz, all part of designated ISM band. Though, the wireless systems have become more reliable, compact and easy to develop than before, a detailed performance analysis and characterization of the devices should be done. This report details the performance analysis and characterization of a popular binary FSK transceiver TRF6901 from Texas Instruments. The performance analysis of the device is done with respect to the TRF/MSP430 demonstration and development kit.

High-speed transmission over contemporary communication networks has drawn many research efforts. Traffic scheduling schemes which play a critical role in managing network transmission have been pervasively studied and widely implemented in various practical communication networks. In a sophisticated communication system, a variety of applications co-exist and require differentiated Quality-of-Service (QoS). Innovative scheduling schemes and hybrid scheduling disciplines which integrate multiple traditional scheduling mechanisms have emerged for QoS differentiation. This study aims to develop novel analytical models for commonly interested scheduling schemes in communication systems under more realistic network traffic and use the models to investigate the issues of design and development of traffic scheduling schemes. In the open literature, it is commonly recognized that network traffic exhibits self-similar nature, which has serious impact on the performance of communication networks and protocols. To have a deep study of self-similar traffic, the real-world traffic datasets are measured and evaluated in this study. The results reveal that selfsimilar traffic is a ubiquitous phenomenon in high-speed communication networks and highlight the importance of the developed analytical models under self-similar traffic. The original analytical models are then developed for the centralized scheduling schemes including the Deficit Round Robin, the hybrid PQGPS which integrates the traditional Priority Queueing (PQ) and Generalized Processor Sharing (GPS) schemes, and the Automatic Repeat reQuest (ARQ) forward error control discipline in the presence of self-similar traffic. Most recently, research on the innovative Cognitive Radio (CR) techniques in wireless networks is popular. However, most of the existing analytical models still employ the traditional Poisson traffic to examine the performance of CR involved systems. In addition, few studies have been reported for estimating the residual service left by primary users. Instead, extensive existing studies use an ON/OFF source to model the residual service regardless of the primary traffic. In this thesis, a PQ theory is adopted to investigate and model the possible service left by selfsimilar primary traffic and derive the queue length distribution of individual secondary users under the distributed spectrum random access protocol.