A digital signal processing system developed for the optimal use of high density magnetic storage media

High density data recording has traditionally been an essential factor in the development of communication and transmission systems. However, recently more sophisticated applications, including video recording, have necessitated refinements of this technology. This study concentrates on the signal processing techniques used to inhance the packing density of stored data. A comparison of the spectral mapping characteristics of different codes illustrates that the need for equalization can be eliminated and that significant bandwidth reduction can be achieved. Secondly, consideration is given to the deleterious effects of flutter, its associated effects on high density data recording, and the constraints imposed on the development of a time base corrector. An analysis is made of the bandlimiting effect which results when the incoming data is convolved with the head impulse response. The bandwidth of the channel, the size of the head gap, and the velocity of the media are seen from this analysis to be intrinsically related. These signal processing techniques are implemented, the channel capacity computed, and a significant channel efficiency achieved