Non-linearity correction

A non-linearity correction circuit, comprising:

• a data path comprising:
• a first digital step attenuator (DSA);
• a first analog-to-digital converter (ADC);
• a first data capture circuit coupled to the first ADC;
• and
• a first time-to-frequency conversion circuit coupled to the first data capture circuit;
• a reference path comprising:
• a second DSA comprising an input coupled to an input of the first DSA;
• a second ADC coupled to the second DSA;
• a second data capture circuit coupled to the second ADC;
• a second time-to-frequency conversion circuit coupled the second data capture circuit;
• a channel estimation circuit coupled to the first time-to-frequency conversion circuit and the second time-to-frequency conversion circuit;
• a channel equalization circuit coupled to the channel estimation circuit and the second time-to-frequency conversion circuit;
• and
• a source non-linearity subtraction circuit coupled to the channel equalization circuit and the first time-to-frequency conversion circuit;
• and
• a non-linearity term generation circuit coupled to the first data capture circuit and the first time-to-frequency conversion circuit;
• a bin identification circuit coupled to the source non-linearity subtraction circuit and the first time-to-frequency conversion circuit;
• a residual non-linearity conversion circuit coupled to the bin identification circuit;
• and
• a non-linearity coefficient generation circuit coupled to the bin identification circuit and the residual non-linearity conversion circuit.

A method for non-linearity correction, comprising:

• receiving a signal as input to a main data path and a reference data path;
• digitizing the signal by a first analog-to-digital converter (ADC) of the main data path and by a second ADC of the reference data path;
• subtracting output of the second ADC from output of the first ADC to produce reference subtracted signal;
• estimating non-linearity correction coefficients based on the reference subtracted signal;
• and
• applying the non-linearity correction coefficients to the output of the first ADC to generate non-linearity corrected data.