Patent ID: 7454223
Filing Date: 2008-11-18
Classification: H04W

Abstract:
1. A method of increasing the accuracy of a base station's estimate of additional uplink transmit power available for a subscriber station that has a radio that includes a power amplifier including foldback circuitry that monitors a current in said power amplifier indicative of actual uplink transmit power provided by said power amplifier to an antenna, said foldback circuitry operating to limit said monitored current to prevent said power amplifier from being driven over specification or being driven outside regulatory limits, said method comprising: maintaining at said base station an estimated value for allowable maximum uplink transmit power for said subscriber station; tracking at said subscriber station incidents of foldback, an incident of foldback occurring whenever said foldback circuitry operates to limit said monitored current to prevent said power amplifier from being driven over specification or being driven outside regulatory limits; transmitting a foldback event message from said subscriber station to said base station whenever incidents of foldback tracked at said subscriber station reach a predetermined threshold; decreasing said estimated value when said base station receives a foldback event message from said subscriber station; increasing said estimated value when a predetermined interval of time has lapsed without said base station receiving a further foldback event message from said subscriber station; and subtracting uplink transmit power reported by said subscriber station from said estimated value to estimate additional uplink transmit power currently available to said subscriber station, when an accurate estimate of said additional uplink transmit power is required.