Abstract: In cellular communication systems, hand-offs are performed to maintain links as subscriber units (110) and cells (420, 450) move relative to each other. The hand-off process is improved by using a pre-stored time-based cell map (400) and precise geo-location data. This information is used to set a hand-off timer for deterministically initiating the hand-off process in the current cell (500). The timer diminishes the amount of power monitoring which is required in the hand-off initiation process. This capability is especially important in satellite communication systems with fast moving cells and sharp boundaries.

Abstract: A control facility (130) within a wireless communication system receives, from a communication unit (120) (CU), a power measurement (306) of a signal (150) projected by a transceiver node (102). The power measurement (306) can be associated with location information (304) for the CU (120) and a time stamp (302). The control facility (130) uses this information to determine whether the CU (120) is being provided with a signal (150) having an acceptable link margin. If not, the control facility mitigates (408, 508, 512, 514, 518, 520) the effects of the unacceptable link margin, if possible. When power measurements (306) are received from multiple CUs (120), the control facility (130) can use the measurements (306) to create (402, 502) a link margin map which correlates CU location (304) with power measurements (306). The map is used to analyze the link margins within the system.