Patent ID: 8218526
Filing Date: 2012-07-10
Classification: H04J,H04W

Abstract:
1. A method for maintaining synchronization in a cellular network between a plurality of user equipment (UE) in a cell and a base station (eNB) serving the cell, comprising: maintaining synchronization of each UE in the scheduled group with the eNB by sending a timing adjustment (TA) command if needed in response to receiving a scheduled transmission from each respective UE in the scheduled group; determining a maximum TA rate expected for the cell; and maintaining synchronization of each UE in the unscheduled group with the eNB by allocating a periodic reference signal (sync-RS) to each UE in the unscheduled group and by sending a respective TA command if needed in response to a respective sync-RS received from each UE in the unscheduled group, wherein the sync-RS period is configured by the eNB to be approximately equal to the inverse of the maximum TA rate expected in the cell.