METHOD AND APPARATUS FOR CDMA SOFT HANDOFF FOR DISPATCH GROUP MEMBERS

摘要

To address the need to provide listening participants of CDMA dispatch services soft handoff signaling capability, the concept of "shared channel signaling windows" for shared traffic channels (e.g., 110) is described. In one embodiment, the base site (105) announces the beginning of a signaling window for the traffic channel, allowing remote units (e.g., MS 120) that need to send handoff signaling an opportunity. In response to such signaling, the base site directs soft handoff information to the signaling remote units via the traffic channel. However, all the remote units that share the traffic channel can store this soft handoff information and later use the information to initiate soft handoffs without needing to exchange handoff messaging with the base site. Thus, a CDMA-dispatch, shared-channel implementation is enabled by providing soft handoff signaling windows and the over-the-air, soft-handoff messaging required for dispatch services is reduced.