Source and network coding on mobile devices

This project concerns the development and implementation of a full functional demonstrator for cooperative wireless networking and network coding, which is a technology for improving performance in wireless networks. An application for distribute a video among nodes forming a cooperative cluster is implemented. The implementation is done for the Maemo platform. In Cellular Controlled Peer-to-Peer (CCP2P) networks, besides being connected to an outside world using cellular links, a group of mobile devices in close proximity form a cooperative cluster contributing their onboard capabilities and resources to exploit them a more efficient way. This project implements this kind of networks. Diverse cooperating phones agree on splitting a video to download and start to receive it through USB from a server (simulating the cellular link). Simultaneously the received data is exchanged over the short-range link using three different transmission schemes: Network coding and broadcast, which were implemented in a previous work, and a new hybrid schema developed as a combination of both, broadcast and network coding. After implementation of the program, tests are carried out, to see the results achieved with this new schema and compare it with the previous ones, in terms of throughput, energy consumption and necessary time to distribute the whole video. The results obtained show an improvement in the three cases for the new hybrid schema, which use broadcast at the beginning, when all the nodes are interested in all the packets, and Network Coding for retransmissions of packets

Game-theoretic Resource Allocation Methods for Device-to-Device (D2D) Communication

Device-to-device (D2D) communication underlaying cellular networks allows mobile devices such as smartphones and tablets to use the licensed spectrum allocated to cellular services for direct peer-to-peer transmission. D2D communication can use either one-hop transmission (i.e., in D2D direct communication) or multi-hop cluster-based transmission (i.e., in D2D local area networks). The D2D devices can compete or cooperate with each other to reuse the radio resources in D2D networks. Therefore, resource allocation and access for D2D communication can be treated as games. The theories behind these games provide a variety of mathematical tools to effectively model and analyze the individual or group behaviors of D2D users. In addition, game models can provide distributed solutions to the resource allocation problems for D2D communication. The aim of this article is to demonstrate the applications of game-theoretic models to study the radio resource allocation issues in D2D communication. The article also outlines several key open research directions.Comment: Accepted. IEEE Wireless Comms Mag. 201

Device-Centric Cooperation in Mobile Networks

The increasing popularity of applications such as video streaming in today's mobile devices introduces higher demand for throughput, and puts a strain especially on cellular links. Cooperation among mobile devices by exploiting both cellular and local area connections is a promising approach to meet the increasing demand. In this paper, we consider that a group of cooperative mobile devices, exploiting both cellular and local area links and within proximity of each other, are interested in the same video content. Traditional network control algorithms introduce high overhead and delay in this setup as the network control and cooperation decisions are made in a source-centric manner. Instead, we develop a device-centric stochastic cooperation scheme. Our device-centric scheme; DcC allows mobile devices to make control decisions such as flow control, scheduling, and cooperation without loss of optimality. Thanks to being device-centric, DcC reduces; (i) overhead; i.e., the number of control packets that should be transmitted over cellular links, so cellular links are used more efficiently, and (ii) the amount of delay that each packet experiences, which improves quality of service. The simulation results demonstrate the benefits of DcC