Synchronization detection methods and apparatus

摘要

Methods and apparatus for determining when uplink synchronization has been achieved when entering or adding a link in soft handover to a new node in a communication system. Transmit power control (TPC) commands from the new link are not included in a TPC command combination until an uplink synchronization detector determines that synchronization has been achieved. Since in many communication systems, a pattern of TPC commands is transmitted on the new downlink as long as the new node's uplink is not synchronized, the uplink synchronization detector can determine whether synchronization has been achieved by determining whether the TPC command pattern is present in the new downlink. In this way, the UL synchronization detector reduces the occurrence and magnitude of unwanted peaks and dips in uplink transmitted power.