Experimental determination of reader resolution using PRS patterns and application to media cluster size measurement

A technique to determine experimentally the reader resolution in magnetic recording by using pseudo-random sequence (PRS) patterns written on the disc is presented. The spectrum of the PRS signal is analyzed to extract simultaneously the width of the magnetic transitions and the reader sensitivity as a function of frequency. When playback spacing is increased, reader sensitivity rolls off faster with frequency, in good quantitative agreement with modeling results involving micromagnetic simulation of the reader. The reader sensitivity is further employed to de-convolve the magnetic cluster size from measured spectra of media noise.