Channel capacity of M-ary multitrack runlength limited channels

We consider M-ary, multitrack runlength limited (d,k) constrained channels with and without clock redundancy. We calculate the Shannon capacities of these channels and present some simple 100% efficient codes. To compute capacity a constraint graph equivalent to the usual runlength limited constraint graph is used. The introduced graph model has a vertex labeling independent of N, the number of tracks to be written on (in parallel), which provides computational savings when the number of tracks is large. We show that increasing the number of tracks provides a significant increase of per-track capacity for more restrictive clocking, i.e. When kd.