Adaptive equalization employing pattern recognition

Apparatus for signal equalization, the apparatus comprising:

• an equalizer applying equalization to an input signal, the equalization characterized by an eye profile;
• a threshold checking module (TCM) adapted to i) monitor the eye profile of the equalized input signal for the presence or absence of a predetermined signal pattern, and ii) detect the presence or absence of the predetermined signal pattern from the eye profile;
• wherein
• the equalizer is further adapted to modify the equalization applied to the input signal based upon the detected presence or absence of the predetermined signal pattern, and wherein the equalizer comprises an adaptive equalizer configured to modify the equalization based on the detected presence or absence of the predetermined pattern by setting at least one of a vertical threshold and a horizontal threshold of a upper latch associated with an upper eye of the eye profile and setting at least one of a vertical threshold and a horizontal threshold of a lower latch associated with a lower eye of the eye profile.

Apparatus for signal equalization, the apparatus comprising:

• an equalizer applying equalization to an input signal, the equalization characterized by an eye profile;
• a threshold checking module (TCM) adapted to i) monitor the eye profile of the equalized input signal for the presence or absence of a predetermined signal pattern, and ii) detect the presence or absence of the predetermined signal pattern from the eye profile;
• wherein
• the equalizer is further adapted to i) modify the equalization applied to the input signal based upon the detected presence or absence of the predetermined signal pattern, and ii) delay modification of the equalization over several detected instances of the predetermined pattern in the input signal.

A method of signal equalization, the method comprising the steps of:

• a) applying equalization to an input signal, the equalization characterized by an eye profile, further comprising:
• a1) applying analog equalization to the input signal based on analog equalizer parameters from an adaptive equalizer to provide an analog equalized signal;
• a2) applying decision feedback equalization (DFE) to the analog equalized signal, where the DFE is based on DFE parameters from the adaptive equalizer and based on previous decisions for data in the input signal;
• b) monitoring the eye profile of the equalized input signal for the presence or absence of a predetermined signal pattern;
• c) detecting the presence or absence of the predetermined signal pattern from the eye profile;
• and
• d) modifying the equalization applied to the input signal based upon the detected presence of the predetermined signal pattern.

A method of signal equalization, the method comprising the steps of:

• a) applying equalization to an input signal, the equalization characterized by an eye profile;
• b) monitoring the eye profile of the equalized input signal for the presence or absence of a predetermined signal pattern;
• c) detecting the presence or absence of the predetermined signal pattern from the eye profile;
• and
• d) modifying the equalization applied to the input signal based upon the detected presence of the predetermined signal pattern by setting at least one of a vertical threshold and a horizontal threshold of a upper latch associated with an upper eye of the eye profile and setting at least one of a vertical threshold and a horizontal threshold of a lower latch associated with a lower eye of the eye profile.

A method of signal equalization, the method comprising the steps of:

• a) applying equalization to an input signal, the equalization characterized by an eye profile;
• b) monitoring the eye profile of the equalized input signal for the presence or absence of a predetermined signal pattern;
• c) detecting the presence or absence of the predetermined signal pattern from the eye profile;
• d) modifying the equalization applied to the input signal based upon the detected presence of the predetermined signal pattern;
• and
• e) delaying modification of the equalization over several detected instances of the predetermined pattern in the input signal.