Patent ID: 7164660

Claim:
A method of operating a radio communication system that includes a downlink channel for transmissions by a primary station to at least one secondary station and an uplink channel for transmissions from the secondary station to the primary station, the method comprising: transmitting a first signal from the primary station on the downlink channel that includes an indication of the transmit power level used for the transmitting, determining radio channel characteristics of the downlink channel at the secondary station, based on the indication of the transmit power level, transmitting an uplink signal from the secondary station on the uplink access channel giving an indication of the radio channel characteristics, and transmitting a signal from the primary station on the downlink channel at a power level and/or bit rate which takes into account the indication of the radio channel characteristics, wherein the secondary station: retransmits an access preamble signal at successively increasing power levels until an acknowledgement signal is received from the primary station, and in response to the receipt of an acknowledgement signal, transmits a message containing an indication of the power level associated with the access preamble signal for which the acknowledgement signal was received.