Distributed Separate Coding for Continuous Data Collection in Wireless Sensor Networks

In this article, we present a novel distributed separate coding (DSC) scheme for continuous data collection in wireless sensor networks with a mobile base station (mBS). By separately encoding a certain number of data segments in a combined segment and doing decoding-free data replacement in the buffers of each sensor node, the DSC scheme is shown as an efficient method for continuously collecting data segments with a high success ratio. The proposed DSC scheme has a salient feature: with a minimum buffer size 2 in each sensor node, by querying any m−1 sensor nodes, the mBS can reconstruct the m latest data segments with high probability, where m is the number of latest data segments in a time interval t in which n(t) (m≤ n(t)) data segments are generated. The necessary storage space in each sensor node can be adjusted by changing the number of sensor nodes queried by the mBS. Furthermore, the transmission cost for data submission to the mBS can be reduced with some additional storage space in each sensor node. The comprehensive performance evaluation has been conducted through computer simulation. It is shown that the proposed DSC scheme outperforms the existing scheme significantly.