A Harmonic Analysis of Saturation Recording in a Magnetic Medium

A single write-read head coupled with saturation recording techniques is commonly used to store digital information. Because of the experimental difficulty in determining the contribution of individual parameters to the system, a theoretical equation describing the output of a system in terms of the physical, magnetic, and electrical parameters of the system has been developed and programmed for the IBM 704 Data Processing System. When applied to an experimental NRZ system, excellent agreement between observed and calculated results was obtained. The phenomena of peak or phase shift and amplitude shift occurring for an isolated pair of adjacent ones at high bit densities is demonstrated and discussed. The calculated dependence of the zero-to-peak output and the peak-and-amplitude shifts is shown for variations in the thickness, retentivity, coercivity and squareness of the storage medium, and for variations in the write current, the head-to-medium spacing, and the pole gap dimensions.