| 摘要 |
A handoff technique in which system users detect transitions in service between a current service area (B10, S4) and an adjacent service area (B2, S5), and request a forward link channel in the new service area (B2, S5) when a detected signal strength for the new service area exceeds predetermined threshold levels. The forward communications link in the current service area is maintained until the strength of the new service area signal (B2, S5) reaches a certain level and appropriate channel quality is confirmed, as based on various known criteria. Typically, service area transitions are detected using the signal strength of pilot or paging signals associated with service areas, which are used to determine a relative signal strength of new service area signals. Pilot signal level adjustments used to counter roll-off effects are detected and compensated for in comparing signal levels . To minimize the burden on system resources, new service area signals are not selectable until a minimum time has passed, or a minimu m change in energy from a prior pilot signal is detected. In addition, communications using the previous service area can be dropped almo st immediately upon engaging the new service area.
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