Research On Cross-layer Spectrum Sensing Method In Clustered Wireless Sensor Networks

With the rapid development, wireless sensor networks are getting more and more attention.Meanwhile, its limited node energy issues and spectrum scarcity problems have becomeincreasingly prominent Arming to this problem, this paper introduces the cognitive radio technologyinto wireless sensor networks, and focuses on spectrum sensing technology.Firstly, by comparison of several typical routing protocols, this paper chooses improvedLEACH protocol as the basis of this research and selects perception node in the cluster by clusterhead.Secondly, this paper puts forward the cross-layer design of MAC layer and the physical layerin wireless sensor networks, and proposes cross-layer spectrum sensing model. Cluster head on onehand avoids nodes which are in the data transmission timeslot when selects perception nodes in thecluster, on the other hand, it selects the largest residual energy nodes and takes double-thresholdcooperative spectrum sensing method. By this way, this spectrum sensing model reduces the nodes’perception energy at the same time makes the cluster node energy balancing.Thirdly, in order to further improve the spectrum detection reliability, after putting forwordsingle-node spectrum sensing model, cooperative spectrum sensing technology is leaded intocross-layer spectrum sensing model in this paper.Lastly, with the combination of the spectrum sensing scheme above, this paper improves datatransmission algorithm in LEACH protocol, and by using dual-band data transmission method, iteffectively reduces the communication delay between cluster head node and cluster member nodes.The experimental results show that the proposed cross-layer spectrum perception method canguarantee the system frequency spectrum detection performance, at the same time save the energyconsumption of the nodes, and make the network nodes energy equilibrium. Through the use ofdouble frequency band data transmission method, Real-time performance of data communication isimproved and the problem of spectrum resources shortage is alleviated efficiently in the cluster.