Method for handoff during connected mode of a multimode mobile station in a mixed deployment

摘要

Methods for handoff of a multimode mobile station (MS). The MS, in connected mode, moves from a cell of a legacy base station to a cell of an ABS and scans base stations from a list of neighbouring base stations, wherein at least the ABS is listed as another legacy base station in the list of neighbouring base stations. The MS performs the handoff to connect to a legacy zone of the ABS. Further, the multimode MS switching from the legacy zone of the ABS to a advanced zone of the ABS based on a Zone Switch request or command is triggered by either the multimode MS or the ABS. The Zone Switch request is triggered after detecting capabilities of either the multimode MS or the ABS that they support advanced zone. The capabilities are detected by using MAC versions of the multimode MS and the ABS or an indicator for the advanced zone. The multimode MS can also performs handoff to the advanced zone from the cell of the legacy base station by receiving one or more information items for ranging in the advanced zone from the ABS during the handoff.