On the capacity of the noisy runlength channel

The authors consider the model for runlength coded systems of P.H. Siegel (1982) that is based on peak or edge detection. The model does not attempt to account for failures of the qualifying circuit; it is assumed that every transition is successfully declared (i.e., no missing or false qualifiers). In this model it is the error in the estimate of the location of the transition that introduces uncertainty at the channel output. The model is motivated by the problem of pulse location in white Gaussian noise. Through a series of lemmas and theorems, bounds on the capacity of this model are obtained. These bounds are evaluated and used to suggest that improvements in storage capacity are possible through the use of codes with designed noise tolerance.