Patent ID: 8180011

Claim:
A method for acquisition and tracking of a recovered clock signal using an inter-symbol interference (ISI) pattern-weighted early-late phase detector, the method comprising: receiving an electromagnetic waveform representing an analog serial data stream; generating an I clock and Q clock having a fixed phase delay with respect to the I clock; dividing the I clock frequency by n, creating a reference clock; sequentially sampling the serial data stream with the I clock, creating digital I-bit values; sequentially sampling the serial data stream with a Q clock, creating digital Q-bit values; segmenting the I-bit values into n-bit digital words; segmenting the Q-bit values into n-bit digital words; in response to analyzing the I-bit and Q-bit values, identifying an I clock phase correction; identifying bit sequence patterns associated with each I-bit value; weighting each I-bit value in response to the identified bit sequence pattern and the identified I clock phase correction; averaging the weighted I-bit values for each n-bit digital word, generating a digital phase error signal; and, in response to the phase error signal, creating an electromagnetic signal representing the I clock, modified in phase.