On extremely high density digital recording
J. Mallinson · IEEE Transactions on Magnetics · 1974
Several recording systems now operate at 106bits per square inch; their performance is partly governed by mechanical defects. The efficiency of systems without such defects would be determined by the signal-to-noise ratio. We show that reliable operation at 107bits per square inch is then possible and this, for example, might make tape-area-efficient broadcast-quality digital video recorders feasible. The ultimate densities given by information theory are demonstrated to be in the range 108- 109bits per square inch.