Isi pattern-weighted early-late phase detector with function-controlled oscillation jitter tracking

Abstract

An inter-symbol interference (ISI) pattern-weighted early-late phase detector is provided. An I clock and a function-controlled oscillation cycle phase delay Q clock are generated. The I clock frequency is divided by n, creating a reference clock. A serial data stream is sequentially sampled with the I clock, and with the function-controlled varied phase delay Q clock, creating digital I-bit and varied phase delay Q-bit values, respectively. The values are segmented into n-bit digital words. I clock phase corrections are identified and a modulation factor is determined in response to comparing varied phase delay Q-bit values with I-bit values. Also identified are bit sequence patterns associated with each I-bit value. Each I-bit value is weighted in response to the identified bit sequence pattern and the identified I clock phase correction. The modulation factor is applied to the weighted average, and I and Q clock phase error signals are generated.