Efficient Mobile Data-Gathering with Space Division Multiple Access Technique in Wireless Sensor Networks

Abstract

In this paper, we propose a new mobile data-gathering technique in wireless sensor networks. The mobile collector, called MobCar in this paper, directly visits all sensors and collects data by single hop from it. We also apply SDMA technique to data collecting by equipping each MobCar with multiple antennas such that distinct compatible sensors may successfully uploading data to a MobCar concurrently. Since data packets are directly gathered without relays and collisions, the energy consumption on data gathering reduces. We aim to minimize the total data collecting time, which consists of the travelling time of the MobCar and the data uploading time of sensors, by exploring the trade-off between the shortest moving path and the full utilization of SDMA. Here, we propose a SDMA based data gathering algorithm is used to find the polling points which collects the data from its neighbors. A MobCar visits each polling point and collects the data from nearby sensors concurrently using SDMA then forwards it to the sink node thus reducing the data gathering latency and energy consumption on data gathering and hence lifetime of the network gets increased. We carry out extensive simulations and the results demonstrate that our proposed algorithms can greatly shorten the moving distance of the MobCars and data gathering latency compared with the existing algorithms.