Method and apparatus for hard handoff in a CDMA system

Abstract

In a communications network, a network user communicates through a remote unit with another user via at least one base station. The communications network includes a first mobile switching center which controls communications through a first set of base stations including a first base station. The remote unit stores a list of active base stations which has an entry corresponding to each base station with which active communication is established. The first base station has an entry on the list of active base stations. The first base station measures a round trip delay of an active communication signal between the first base station and the remote unit. A handoff of the active communication signal is initiated if the round trip delay of the active communication exceeds a threshold if the first base station is designated as a reference base station. Alternatively, the remote unit also stores a list of candidate base stations comprising an entry corresponding to each base station through which active communication may be possible but is not established. A handoff of the active communication signal is initiated if the list of candidate base stations comprises an entry corresponding to a triggering pilot signal.

Dependencies are inferred from the claim text.