Systems And Methods For Transmitting And Receiving Auxiliary Data

A method for transmitting data in a data transmission system, the method comprising:

• receiving regular data bits and auxiliary data bits at a transmitter circuit;
• encoding a first subset of the regular data bits with the transmitter circuit to generate a first subset of encoded data comprising pairs of symbols that are used for encoding in quadrature amplitude modulation;
• encoding the auxiliary data bits and a second subset of the regular data bits with the transmitter circuit to generate a second subset of the encoded data comprising at least one pair of symbols that are unused for encoding by the quadrature amplitude modulation;
• and
• generating a modulated output signal that indicates the first and second subsets of the encoded data using pulse amplitude modulation with the transmitter circuit.