Computer Simulation of Waveform Distortions in Digital Magnetic Recordings

When frequency or phase modulation is applied to digital magnetic recording, both peak shift and amplitude variation occur in the readback signals. These distortions are due specifically to pulse crowding, noise, and variation of separation between read head and recording medium. When such waveform distortions are simulated on the digital computer, the results agree well with those obtained from a time-consuming experimental method, and are more accurate than an approximate analytical solution. Simulation results are also produced in graphical form, and thus provide an additional guide for designing and evaluating the performance of optimal recording systems.