Abstract: A cellular communications system is provided having both surface and satellite nodes which are fully integrated for providing service over large areas. Two-way adaptive power control and signal quality monitoring and power control responsive thereto are provided for controlling the power output levels of transmitters to the minimum necessary for satisfactory communications. Each transmission includes a code representative of the transmitter output power level. Receivers compare this code to the received signal strength and adjust their associated transmitter power output level accordingly. Bit error rate and SNR are monitored by receivers to develop a measure of signal quality. A signal quality code is transmitted to remote units and transmission output power level is adjusted in response. Timing signals are provided by one or more nodes to obtain user position information.