Multirate Data Collection Using Mobile Sink in Wireless Sensor Networks

Data collection is one of the most fundamental and important operations in applications of wireless sensor networks (WSNs). Recent research has shown that using mobile sink to collect data brings many advantages to WSNs, such as improving energy efficiency of sensor nodes and prolonging network lifetime. However, the limited speed of mobile sink leads to larger latency, which cause that the data is not fresh or the buffer overflow problem of static sensor nodes. Based on the adaptive rate control, this paper proposes a data collection algorithm which aims to reduce the length of path along which mobile sink collects data from static sensor nodes. The proposed algorithm not only guarantees the completeness of data collection from each static node but also reduces path length by adopting appreciate transmission rate. Through extensive simulations, experimental results show that our approach can notably reduce the path length of mobile sink, while the data of every sensor can be collected completely and efficiently.