Design of Mobile Sink Node for SDMA Applications in WSN

Recent years have witnessed a surge of Interest in efficient data collection schemas in wireless sensor networks (WSNs). However, there are some serious problems existing in static wireless sensor networks such as energy hole, overlapping and hot spots, etc. An efficient method to solve these problems is using mobile nodes. Through data collection and relaying, mobile nodes can reduce the data of transmitting between the static nodes. It also conserve the power of static nodes and therefore can prolong the lifetime of network. In this paper, we introduce the design and implementation of a mobile sink node based on ARM7 core chip, named DataTruck, which has a large storage and rapid speed. Furthermore, we integrate a smart antenna system to collect the data from multiple static nodes concurrently which use the same frequency. We consider applying space-division multiple access (SDMA) technique to data gathering by equipping the DataTruck with two antennas. With SDMA, two distinct compatible sensors may successfully make concurrent data uploading to the DataTruck. Experiments show that DataTruck can collect data efficiently and reduce the average data delay by using SDMA technology.