The present invention provides a method and an apparatus for managing
relocation of one or more scrambling codes in a spread spectrum wireless
communications system. The method comprises detecting an indication for a
serving radio network subsystem relocation that causes a user equipment
to leave a first radio network controller and selectively transiting,
through an intermediate transition, at least one scrambling code of the
one or more scrambling codes associated with an uplink from the first
radio network controller to a second radio network controller for the
user equipment in response to the indication. The first radio network
controller may maintain three pools of scrambling codes, namely, a first
pool of one or more relocated scrambling codes (SCs), a second pool of
one or more free scrambling codes and a third pool for each of one or
more used scrambling codes. By avoiding an early reuse, an uplink
scrambling code may be assigned to a particular UE because a target radio
network controller, i.e., a new serving radio network controller may use
the same scrambling code as long relocated user equipment maintains a
current call. In this way, an uplink scrambling code defined for a
serving radio network subsystem relocation procedure based on 3GPP
standards may be consistent across disparate vendor solutions.