Abstract: A method of transferring a data message from a remote unit to a central location is provided. A plurality of data channels is selected for transmitting the data message from the remote unit to the central location. At least one random transmit time is generated for transmitting the data message for each of the plurality of data channels. The data message is transmitted over the plurality of data channels at the transmit times. An apparatus for transferring a data message from a remote unit to a central location is also provided.

Abstract: Automatic level calibration apparatus for transmitting data from a cable television terminal to the headend of a cable television system comprises programmable transmitter apparatus of the terminal, programmable receiving apparatus at the headend and a calibration controller. Responsive to an addressed command from the headend, the programmable transmitter apparatus returns a sequence of levels at a particular calibration frequency. The programmable receiver apparatus determines an indication of the received signal strength of each of the levels of the sequence of levels. The controller determines an optimum level for transmissions from the terminal.

Abstract: A cable television radio frequency data processor for receiving and processing data transmitted from a cable television terminal to the headend of a cable television system comprises a plurality of data receivers for receiving the returned data, detectors associated with each receiver for providing an indication of received signal strength and a data processor. The data processor responsive to the data receivers eliminates redundant data and collects statistics on data throughput and, responsive to the detectors, collects statistics on received signal strength. The data processor then may initiate recalibration of transmit signal levels or an appropriate selection of data transmit channels as required.