Fast distributed multi-hop relative time synchronization protocol and estimators for wireless sensor networks

Simple item page
dc.citation.epage2344fr_FR
dc.citation.issue8fr_FR
dc.citation.spage2329fr_FR
dc.citation.volume11fr_FR
dc.contributor.authorDjenouri, Djamel
dc.contributor.authorMerabtine, Nassima
dc.contributor.authorMekahlia, Fatma Zohra
dc.contributor.authorDoudou, Messaoud
dc.date.accessioned2013-12-13T20:15:02Z
dc.date.available2013-12-13T20:15:02Z
dc.date.issued2013-11
dc.description.abstractThe challenging problem of time synchronization in wireless sensor networks is considered in this paper, where a new distributed protocol is proposed for both local and multi-hop synchronization. The receiver-to-receiver paradigm is used, which has the advantage of reducing the time-critical-path and thus improving the accuracy compared to common sender-to-receiver protocols. The protocol is fully distributed and does not rely on any fixed reference. The role of the reference is divided amongst all nodes, while timestamp exchange is integrated with synchronization signals (beacons). This enables fast acquisition of timestamps that are used as samples to estimate relative synchronization parameters. An appropriate model is used to derive maximum likelihood estimators (MLE) and the Cramer-Rao lower bounds (CRLB) for both the offset-only, and the joint offset/skew estimation. The model permits to directly estimating relative parameters without using or referring to a reference’ clock. The proposed protocol is extended to multi-hop environment, where local synchronization is performed proactively and the resulted estimates are transferred to the intermediate/end-point nodes on-demand, i.e. as soon as a multi-hop communication that needs synchronization is initiated. On-demand synchronization is targeted for multi-hop synchronization instead of the always-on global synchronization model, which avoids periodic and continuous propagation of synchronization signals beyond a single-hop. Extension of local MLE estimators is proposed to derive relative multi-hop estimators. The protocol is compared by simulation to some state-of-the-art protocols, and results show much faster convergence of the proposed protocol. The difference has been on the order of more than twice compared to CS-MNS, more than ten times compared to RBS, and more than twenty times compared to TPSN. Results also show scalability of the proposed protocol concerning the multi-hop synchronization. The error does not exceed few microseconds for as much as 10 hops in R4Syn, while in CS-MNS, and TPSN, it reaches few tens of microseconds. Implementation and tests of the protocol on real sensor motes confirm microsecond level precision even in multi-hop scenarios, and high stability (long lifetime) of the skew/offset model.fr_FR
dc.identifier.issn1570-8705
dc.identifier.urihttp://dl.cerist.dz/handle/CERIST/487
dc.publisherElsevierfr_FR
dc.relation.ispartofAd hoc Networksfr_FR
dc.rights.holderElsevierfr_FR
dc.structureRéseaux de Capteurs et Applicationsfr_FR
dc.subjectWireless sensor networksfr_FR
dc.subjectTime synchronizationfr_FR
dc.subjectDistributed algorithmsfr_FR
dc.titleFast distributed multi-hop relative time synchronization protocol and estimators for wireless sensor networksfr_FR
dc.typeArticle
Files
Collections
International Journal Papers