SYSTEM AND METHOD FOR PROCESSING MR/GMR HEAD SIGNAL USING PHASE MEASUREMENT

A circuit combines a read signal from an MR/GMR read head with a signal generated by a matched filter, the parameters of which depend on the geometry of the head and the output of which, generated every Nth clock period, includes a real part and an imaginary part that models an expected head response. The combined signal is phase equalized and sent to a complex correlator, which integrates the signal over N clock periods to output a correlated signal having real and imaginary portions of the Nth root of unity which correspond to bits in an N-clock data unit. The real and imaginary portions can subsequently be digitized and analyzed for errors.