Patent ID: 7120092

Claim:
In a communication system including a plurality of non-master nodes being communicatively coupled via a network, each of said plurality of non-master nodes having a local time base, one of said plurality of non-master nodes being designated as a master node having a master time base which serves as a master clock against which said non-master node's local time bases are synchronized, a clock synchronization method for adjusting the local time bases, the method comprising the steps of: in an ith iteration cycle, at said master node: (1) transmitting a synchronization frame, F i , including an i−1th iteration cycle master node time value, a(n i−1 ), and an i−1th iteration cycle sequence number, n i−1 ; (2) detecting, during transmission from said master node, a predefined symbol position associated with said transmitted synchronization frame, F i ; (3) saving an ith iteration cycle master node time value, a(n i ), corresponding to a time of detection of said predefined symbol position; and (4) saving an ith iteration cycle sequence number, n i , corresponding to said synchronization frame, F i ; at each of said non master nodes: (a) receiving said synchronization frame, F i ; (b) detecting, during reception of said synchronization frame, F i , said predefined symbol position; (c) saving an ith iteration cycle non-master node cycle time value, b(n i ), corresponding to a time of detection of said predefined symbol position; (d) saving said ith iteration cycle sequence number, n i corresponding to said synchronization frame, F i ; (e) computing a cycle time difference value as, a(n i−1 )−b(n i−1 ), wherein b(n i−1 ) is an i−1th iteration cycle non-master node time value; and (f) adjusting said non-master node's local time base in accordance with said computed cycle time difference value.