| 主权项 |
1. A method in a slave device to estimate an offset between the slave device and a master device, the method comprising:
receiving a master→slave timing packet; obtaining timing adjustment information pertaining to at least part of a communications path between the slave device and the master device, at least some of the timing adjustment information obtained otherwise than from any received master→slave timing packet, transmit and receive times of the any received master→slave timing packet, and transmit and receive times of any transmitted slave→master timing packet; generating an estimate of the offset using the timing adjustment information and using the transmit and receive times for the master→slave timing packet,wherein said timing adjustment information comprises an indication of a change in the communications path, and wherein said offset is a timing offset computed based on a current mean delay; the method further comprising:
transmitting and receiving timing packets on an ongoing basis to compute the current mean delay; upon receiving said indication of the change in the communications path, estimating a correction of the current mean delay; obtaining a new mean delay using the estimated correction of the current mean delay; detecting a change in communications path to a different communications path by performing at least one of:
receiving a notification of the change of path; anddetecting an out of bounds delay for a timing packet; and after the change in communications path to the different communications path, increasing a frequency of transmitting and receiving timing packets to speed up acquisition of delay characteristics for the different communications path. |
