Mobile Data Gathering with Multiuser MIMO Technique in Wireless Sensor Networks

Recent years have witnessed a surge of the interest in efficient data gathering schemes in wireless sensor networks (WSNs). In this paper, we address this essential issue in WSNs by introducing the mobility and MIMO capability to the data sink in order to optimize the system performance. Specifically, the mobile sink moves along a pre-determined path and collects data packets at some polling stations. With a proper planning on the moving path, we can reduce the data relaying to the minimum, which effectively improves the energy efficiency and also circumvents the non-uniformity of energy consumption among sensor nodes. We also apply MIMO technique to the mobile sink by mounting multiple antennas on it, which provides a radical way to improve the system capacity. With the support of MIMO technique, the mobile sink can simultaneously collect data from multiple compatible sensors. Finally, we theoretically analyze the performance of mobile data gathering in a WSN enhanced by MIMO support, and also investigate its efficiency by simulation experiments. The results demonstrate that the proposed mechanism can greatly improve the system throughput and energy efficiency with minimum additional overhead.