Reliability Assessment Modeling for Star Wireless Sensor Network Based on Copula Function and k / n ( G ) Model

ABSTRACT Traditional reliability models for wireless sensor networks (WSNs) often assume independent node failures, which overlooks the correlated failures prevalent in real‐world engineering scenarios. To address this limitation, this paper proposes a reliability modeling approach for star wireless sensor networks (SWSNs) that integrates Copula functions with a k / n ( G ) system. Based on the cumulative distribution function (CDF) of node lifetimes, we derive an analytical expression for the system reliability function. The SWSN is modeled as a series connection between a sink node and a k / n ( G ) subsystem. Copula functions are used to capture node failure correlations, with parameters estimated via maximum likelihood estimation and the optimal Copula selected using model evaluation criteria. Using simulated lifetime data based on the Weibull distribution, a case study of a 2/3( G ) SWSN demonstrates that the proposed model effectively evaluates system reliability. The Clayton Copula is found to provide the best fit, offering a more accurate and reliable assessment for SWSN.