METHOD FOR HARD HANDOFF IN A CDMA CELLULAR ENVIRONMENT

摘要

A method for performing a hard handoff of a call from a first cell site of a CDMA cellular network to a target cell site of a second cellular network, such as an AMPS network or a second CDMA network. As a mobile unit operating in the first CDMA network moves toward the second cellular network, the first cell site uses two separate RTD thresholds for comparison with a measured RTD distance between the mobile unit and the first cell site. Handoff is initiated when the RTD distance exceeds the first RTD threshold and is completed when the RTD distance exceeds the second RTD threshold. If the first cell site is not co-located with a cell site of the second network, the first cell site utilizes receivers placed in the target cell site for handoff. If the first cell site is co-located with a second cell site of the second network, the second cell site of the second network is always the target cell site.