Signal correction using soft information in a data channel

A method comprising:

• receiving, in at least one soft output detector, an input signal;
• detecting, by the at least one soft output detector, data bits within the input signal;
• outputting, by the at least one soft output detector, detected data bits and corresponding soft information;
• receiving, by a signal correction circuit, the detected data bits and corresponding soft information;
• generating, in the signal correction circuit, expected signal values based on the detected data bits;
• comparing the expected signal values to the input signal to determine a residue term;
• determining, by the signal correction circuit and based on the corresponding soft information and the residue term, a signal correction value;
• and
• returning a corrected signal to the at least one soft output detector.

A system comprising:

• means for detecting data bits within an input signal configured to:
• receive an input signal;
• detect data bits within the input signal;
• and
• output detected data bits and corresponding soft information;
• and
• means for correcting the input signal configured to:
• receive the detected data bits and corresponding soft information;
• generate expected signal values based on the detected data bits;
• compare the expected signal values to the input signal to determine a residue term;
• determine, based on the corresponding soft information and the residue term, a signal correction value;
• and
• return a corrected signal to the means for detecting data bits within the input signal.

A read channel circuit, comprising:

• at least one soft output detector configured to:
• receive an input signal;
• detect data bits within the input signal;
• and
• output detected data bits and corresponding soft information, wherein the at least one soft output detector comprises:
• a front-end soft output detector configured to receive the input signal from an analog front-end circuit;
• and
• an iterative soft output detector configured to:
• receive the input signal from the front-end soft output detector;
• and
• receive the input signal from a prior iteration of the iterative soft output detector;
• and
• a signal correction circuit configured to:
• receive the detected data bits and corresponding soft information;
• determine, based on the corresponding soft information, a signal correction value;
• and
• return a corrected signal to the at least one soft output detector, wherein the signal correction circuit comprises a switch configured to selectively receive the detected data bits and corresponding soft information from the front-end soft output detector and the iterative soft output detector.