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1	Analysis of energy efficiency of cooperative MIMO schemes Krishnan, Narayanan January 1900 (has links) Master of Science / Department of Electrical and Computer Engineering / Balasubramaniam Natarajan / Recently, user-cooperative MIMO (multi-input multi-output) systems have been generating significant interest due to their capacity/performance gains over SISO (single-input single-output) systems. In cooperative MIMO architectures, individual nodes with single antennas collaborate with each other to act as a MIMO unit. As a result, the individual node complexity associated with traditional MIMO implementations is alleviated. This feature is especially beneficial in sensor networks and cellular systems where individual node energy, size and cost are important constraints. Additionally, cooperative MIMO schemes provide all the benefits of traditional MIMO systems. In this work, we classify the cooperative MIMO systems into three different categories equivalent to classical MIMO, MISO and SIMO systems. For the three protocols, we quantify and compare the energy efficiency of Amplify-and-Forward (AF) and Decode-and-Forward (DF) schemes on a basic three node cooperative network. Total energy is calculated considering circuit energy as well as transmission energy. For AF and DF schemes, we set a target Symbol Error Probability (SEP) and evaluate the minimum transmission energy for achieving the target SEP. In this process,we first derive an approximation for SEP at high SNR. Then, we formulate the transmission energy calculation as an optimization problem subject to the target SEP and present the theoretical solution. The result is used to compare the total energy consumption of AF and DF for the three protocols. This is unlike most of the prior efforts that primarily focus on optimum allocation of limited total power to maximize the some peformance criterion. Since any wireless systems in order to operate have a set performance criterion, we intend to minimize the resources that is capable of achieving that. Energy Efficiency Cooperative Wireless Communication SIMO, MISO, MIMO Systems Wireless Networks Resource Utilization
2	Cooperative wireless channel characterization and modeling: application to body area and cellular networks Liu, Lingfeng 23 March 2012 (has links) Cooperative wireless communication is an attractive technique to explore the spatial channel resources by coordination across multiple links, which can greatly improve the communication performance over single links. In this dissertation, we study the cooperative multi-link channel properties by geometric approaches in body area networks (BANs) and cellular networks respectively.<p><p>In the part of BANs, the dynamic narrowband on-body channels under body motions are modeled statistically on their temporal and spatial fading based on anechoic and indoor measurements. Common body scattering is observed to form inter-link correlation between links closely distributed and between links having synchronized movements of communication nodes. An analytical model is developed to explain the physical mechanisms of the dynamic body scattering. The on-body channel impacts to simple cooperation protocols are evaluated based on realistic measurements. <p><p>In the part of cellular networks, the cluster-level multi-link COST 2100 MIMO channel model is developed with concrete modeling concepts, complete parameterization and implementation methods, and a compatible structure for both single-link and multi-link scenarios. The cluster link-commonness is introduced to the model to describe the multi-link properties. The multi-link impacts by the model are also evaluated in a distributed MIMO system by comparing its sum-rate capacity at different ratios of cluster link-commonness. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished Electricité Sciences exactes et naturelles Wireless communication systems Wireless sensor networks Transmission sans fil Réseaux de capteurs sans fil visibility region capacity channel modeling cooperative wireless communication multiple cylinder scattering Doppler spectrum 2.4 GHz IEEE 802.15.6 UWB COST 2100 channel model MIMO cooperative relay cluster DMC BAN body area network distributed MIMO diversity polarization MPC on-body channel dynamic body scattering surface wave fading shadowing pathloss cross-channel correlation

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Analysis of energy efficiency of cooperative MIMO schemes

Cooperative wireless channel characterization and modeling: application to body area and cellular networks