TY - GEN
T1 - On clock offset estimation in wireless sensor networks with weibull distributed network delays
AU - Ahmad, Aitzaz
AU - Noor, Amina
AU - Serpedin, Erchin
AU - Nounou, Hazem
AU - Nounou, Mohamed
PY - 2010
Y1 - 2010
N2 - We consider the problem of Maximum Likelihood (ML) estimation of clock parameters in a two-way timing exchange scenario where the random delays assume a Weibull distribution, which represents a more generalized model. The ML estimate of the clock offset for the case of exponential distribution was obtained earlier. Moreover, it was reported that when the fixed delay is known, MLE is not unique. We determine the uniformly minimum variance unbiased (UMVU) estimators for exponential distribution under such a scenario and produce biased estimators having lower MSE than UMVU for all values of clock offset. We then consider the case when shape parameter is greater than one and reduce the corresponding optimization problems to their equivalent convex forms, thus guaranteeing convergence to a global minimum.
AB - We consider the problem of Maximum Likelihood (ML) estimation of clock parameters in a two-way timing exchange scenario where the random delays assume a Weibull distribution, which represents a more generalized model. The ML estimate of the clock offset for the case of exponential distribution was obtained earlier. Moreover, it was reported that when the fixed delay is known, MLE is not unique. We determine the uniformly minimum variance unbiased (UMVU) estimators for exponential distribution under such a scenario and produce biased estimators having lower MSE than UMVU for all values of clock offset. We then consider the case when shape parameter is greater than one and reduce the corresponding optimization problems to their equivalent convex forms, thus guaranteeing convergence to a global minimum.
KW - Clock synchronization
KW - Estimation
KW - Sensor networks
UR - http://www.scopus.com/inward/record.url?scp=78149492089&partnerID=8YFLogxK
U2 - 10.1109/ICPR.2010.568
DO - 10.1109/ICPR.2010.568
M3 - Conference contribution
AN - SCOPUS:78149492089
SN - 9780769541099
T3 - Proceedings - International Conference on Pattern Recognition
SP - 2322
EP - 2325
BT - Proceedings - 2010 20th International Conference on Pattern Recognition, ICPR 2010
T2 - 2010 20th International Conference on Pattern Recognition, ICPR 2010
Y2 - 23 August 2010 through 26 August 2010
ER -