Patent ID: 7961682
Filing Date: 2011-06-14
Classification: H04W

Abstract:
1. In a CDMA communication system, a method for supporting handoff of a terminal between base stations of different protocol revisions, comprising: performing a handoff of the terminal from a first base station to a second base station, wherein the handoff is performed while the terminal is in an active call with the first base station, wherein the first base station supports a first protocol revision and the second base station supports a second protocol revision that is later than the first protocol revision, wherein the terminal supports a terminal protocol revision, and wherein the protocol revision used between the terminal and second base station is the lower of the terminal protocol revision and the second protocol revision; determining if there is ambiguity at the terminal or the second base station as to which call is being processed; and maintaining the active call between the terminal and the second base station, wherein if there is ambiguity at the terminal or the second base station as to which call is being processed the second base station assigns an identifier to the active call and transmits the identifier to the terminal, and wherein if there is no ambiguity at the terminal or the second base station as to which call is being processed the second base station does not assign the identifier to the active call.