Resource allocation in visual sensor networks using a reinforcement learning framework

In recent years, video delivery over wireless visual sensor networks (VSNs) has gained increasing attention. The lossy compression and channel errors that occur during wireless multimedia transmissions can degrade the quality of the transmitted video sequences. This paper addresses the problem of cross-layer resource allocation among the nodes of a wireless direct-sequence code division multiple access (DS-CDMA) VSN. The optimal group of pictures (GoP) length during the encoding process is also considered, based on the motion level of each video sequence. Three optimization criteria that optimize a different objective function of the video qualities of the nodes are used. The nodes´ transmission parameters, i.e., the source coding rates, channel coding rates and power levels can only take discrete values. In order to tackle the resulting optimization problem, a reinforcement learning (RL) strategy that promises efficient exploration and exploitation of the parameters´ space is employed. This makes the proposed methodology usable in large or continuous state spaces as well as in an online mode. Experimental results highlight the efficiency of the proposed method.