6 Conclusion
The lifetime of the wireless sensor networks can be improved by multiple sink nodes deployment. Congestion is an important issue in multi-sink sensor networks which mitigates the effectiveness and lifetime of the network. Irregular and non-uniform distribution of the sensor nodes and unbalanced loads of the sink nodes are important factors which deteriorate the congestion situation in the sink nodes.
To mitigate the congestion problem in sink nodes and benefit from the multiple sink deployment, in this paper, a fuzzy logic-based sink selection algorithm is presented for one-hop wireless sensor networks. In the proposed distributed sink selection scheme, each sink node should declare its average load with a Hello message to the network. When a sensor node receives this message, it can recognize the congestion situation in the sink node and by using the Received Signal Strength of this message, it can determine its distance with the sink. Then this information along with remaining battery power are applied to a fuzzy inference system to select the nearest uncongested sink node. Extensive simulations indicate the effectiveness of the proposed solution in load balancing the sink nodes, reducing congestion in sink nodes, and mitigating the delay and energy consumption of data transmissions.
In the upcoming researches and studies, we will try to adapt our proposed fuzzy sink selection solution to the multi-hop wireless sensor networks with multiple mobile sink nodes.
