A Cognitive Global Clock Synchronization Method in Wireless Sensor Networks

Clock synchronization in sensor networks quite recently attained great importance and researchers are concentrating their attention on it. It is utmost difficult to get clock synchronization through clock skew and phase offset. Every sensor node has its own internal clock and it is very necessary to get all the clocks of sensor nodes precisely on common time value to achieve good synchronization. In surveillance and law enforcement applications global synchronization is important as precise mapping is required for the collected sensor data. The sensor nodes form a multi-hop and ad-hoc network for such applications. The basic demand for these applications is high accuracy and reduced latency error. The main contribution of this article is: 1. Brief introduction of fault tolerant novelty of the cognitive global clock synchronization algorithm (CGCSA) and 2. In this article we have observed jointly maximum likelihood estimation (JMLE) of the clock skew and clock offset in CGCSA to check its performance in terms of synchronization accuracy and compared our scheme with receiver only synchronization (ROS) strategy.