Prioritizing the Data in the Target-Tracking Wireless Sensor Networks

How to utilize the resources effectively so that good throughput and delay performance can be achieved in the target-tracking wireless sensor networks (WSNs) is a hot topic. In this paper, we introduce a "Queue" as a key structure in the design of our medium access control protocol. By using several narrow out-of -band busy tone signals, the main function of the queue is to keep the right accessing to the data channel for nodes that have sent the control packets successfully. Therefore, it reduces idle time of the data channel. In this paper, we propose and analyze a multi-channel access protocol based on the Queue, i.e., "Queue-based Multi-channel Medium Access Control Protocol" (QMMAC). QMMAC could not only alleviates collision, but also improves the efficiency of system resources because it takes the advantage of parallel transmission of multiple channels adequately. Thus, it can reduce delay and enhance the throughput of the network. Our work is very significant in the target-tracking application for the data coming from the active targets. The data is very important for tracking and is assigned a higher priority, finally, data could be transmitted to the sink with less delay. By taking into account the most complex network scenarios, we analyze the throughput of QMMAC protocol and do simulations to discuss the performance of our protocol. Our analysis and simulation results show that QMMAC achieves significantly better throughput and delay over the protocol without the queue in the same condition.