Patent ID: 7409022

Claim:
A method for synchronizing a transmit clock of a transmitter with a receive clock of a receiver in a wireless communications network, wherein, for the transmit clock, a time t 1 is when a synchronization message is in a MAC layer of the transmitter, a time t 2 is when the synchronization message is in a PHY layer of the transmitter, a time t 3 is when the synchronization message is in a PHY layer of the receiver, and a time t 4 is when the synchronization message is in a MAC layer of the receiver, and corresponding times for the receive clock are t 1 ′, t 2 ′, t 3 ′, and t 4 ′, respectively, comprising: generating the synchronization message in the MAC layer of the transmitter at the time t 1 ; inserting the time t 1 in the synchronization message when the synchronization message is in the MAC layer of the transmitter; passing the message from the MAC layer to the PHY layer; adding an access delay δ to the time t 1 , the access delay being an estimate of a delay required to pass the synchronization message from the MAC layer to the PHY layer; and broadcasting the synchronization message to the receiver.