Adaptive video coding selection scheme for solar-powered wireless video sensor networks

Recently, the use of wireless sensor networks to collect video data for environmental observation or monitoring has been increasing, but they are not suitable for transmitting large video data due to the limitation of node energy. Energy-harvesting node could be used to overcome this limitation, but the harvested energy is also limited. Therefore, an efficient energy utilization method is required to transmit a large amount of video data. This paper proposes a scheme to reduce the number of blackout nodes and increase the amount of collected data by selecting an appropriate video encoding method according to energy condition of the node in a solar-powered wireless sensor network. To collect data continuously regardless of day or night, this scheme allocates the amount of energy that can be used by time, and selects a coding with a high-compression ratio if the allocated amount is large, or a coding with a low-compression ratio if it is small. In this way, the blackouts of relay nodes are reduced and data can be transmitted continuously, which increases the amount of data arriving at the sink node. The simulation results verified confirmed that the proposed scheme prevented the energy exhaustion of the relay nodes and collected more data compared to using one coding only.