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In the context of this project, we worked on the development of a cross-layer resource management system over single hop and multihop Direct-Sequence Code Division Multiple Access (DS-CDMA) Visual Sensor Networks (VSNs). The target was the optimal determination and allocation of the source and channel coding rates and the power levels among the nodes of the considered network. For the efficient allocation of the nodes' transmission parameters, we applied various distortion-related criteria, drawing inspiration from game theory as well, and investigated fairness and efficiency under different perspectives for each of them. Computational intelligence optimization algorithms and reinforcement learning techniques were applied in order to solve the resulting optimization problems. All the solutions provided by the examined schemes were Pareto-optimal and thus, the choice about the most fair and efficient scheme is problem-dependent. Some of the approaches that were taken into account for further improving the end-to-end video distortion of a wireless multiple-access VSN included the time scheduling of transmitting nodes for interference mitigation, the optimal Instantaneous Decoding Refresh (IDR) frame placement during encoding, the content-based node prioritization, and the weighted bi-objective optimization for measuring the trade-off between video quality and consumed transmission power. The evaluation of all proposed approaches showed that enhanced end-to-end video quality can be achieved, by keeping power consumption at reasonable levels, when compared to the case of assigning equal values to the transmission parameters of all nodes constituting the network.

In this work, we discuss multiplayer pervasive games that rely on the use of ad hoc mobile sensor networks. The unique feature in such games is that players interact with each other and their surrounding environment by using movement and presence as a means of performing game-related actions, utilizing sensor devices. We discuss the fundamental issues and challenges related to these type of games and the scenarios associated with them. We also present and evaluate an example of such a game, called the "Hot Potato", developed using the Sun SPOT hardware platform. We provide a set of experimental results, so as to both evaluate our implementation and also to identify issues that arise in pervasive games which utilize sensor network nodes, which show that there is great potential in this type of games.