Patent ID: 6643281
Filing Date: 2003-11-04
Classification: H04B,H04L,H04W

Abstract:
A highly bandwidth-efficient communications method, comprising:forming a synchronization burst at an antenna element of a base station, including a plurality of tone frequencies arranged in a distinctive orthogonal frequency division multiplexed pattern unique to the base station; transmitting the synchronization burst from the antenna element at a base station reference instant of time; receiving the synchronization burst at a remote station during a remote station receive time window which begins at a remote station reference instant of time established by a remote station clock; recognizing the pattern of the plurality of tone frequencies as having the base station as the source of the synchronization burst; transmitting an error signal back to the base station at an instant referenced with respect to the remote station reference instant of time, in response to the recognizing; deriving from the error signal a correction value related to a relative time error between the base station reference instant of time and the remote station reference instant of time; and transmitting the correction value to the remote station to correct the remote station clock.