Compensating for non-linearity in an overlaid communication system

An overlaid radio communication system, comprising:

• a hub station configured to communicate using an outbound signal;
• and
• a terminal configured to communicate using an inbound signal to the hub station, wherein
• the inbound signal from the terminal is overlaid with the outbound signal as a composite signal, the inbound signal having a predetermined spectral configuration, the terminal including,
• a module configured to modify a received composite signal for a non-linear effect based upon a function associated with the non-linear effect, to output an estimate of the inbound signal based upon the modified composite signal, and to filter the estimate of the inbound signal according to the predetermined spectral configuration, wherein the combined signal of the filtered estimate and the canceled second signal is utilized as the estimate of the operating point associated with the non-linearity to further compensate the non-linearity in an iterative manner, the module generating an output signal representing the inbound signal based upon the final estimated operating point.

A device of compensating for non-linearity in an overlaid radio communication system, the device comprising:

• means for modifying a received composite signal for a non-linear effect based upon a function associated with the non-linear effect, wherein the composite signal includes a first signal overlaid onto a second signal, the first signal having a predetermined spectral configuration;
• means for outputting an estimate of the first signal based upon the modified composite signal;
• and
• means for filtering the estimate of the first signal according to the predetermined spectral configuration, wherein the filtered estimate is utilized to refine an estimate of an amplifier operating point associated with the non-linearity, wherein an output signal representing the first signal is generated based upon the refined estimate.

A device of compensating for non-linearity in an overlaid radio communication system, the device comprising:

• a look-up table configured to store information used to determine an inverse function associated with a non-linear effect of a received composite signal, wherein the composite signal includes a first signal overlaid onto a second signal, the first signal having a predetermined spectral configuration;
• a multiplier configured to generate a product of an entry of the look-up table and the received composite signal;
• an estimation module configured to output an estimate of the first signal based upon the product;
• and
• a filter configured to filter the estimate of the first signal according to the predetermined spectral configuration, wherein the filtered estimate is utilized to refine an estimate of the amplifier operating point associated with the non-linearity using the look-up table, wherein an output signal representing the first signal is generated based upon the refined estimate.

A method for generating a waveform used in an overlaid radio communication system, the method comprising:

• generating a plurality of inbound signals having a predetermined spectral configuration;
• and
• overlaying the plurality of inbound signals onto an outbound signal to output a composite signal, the predetermined spectral configuration partially occupying a spectrum of the outbound signal,
• wherein the composite signal is transmitted over a repeater that introduces non-linearity to the composite signal, and the predetermined spectral configuration of the inbound signals is utilized to compensate for the non-linearity.