Author_Institution :
Eng. Res. Center, Eastman Kodak Co., Rochester, NY, USA
Abstract :
We consider multiamplitude, 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 the vertex labeling independent of 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 written on in parallel provides significant increase of per-track capacity for the more restrictive clocking constraint case, i.e., when k
Keywords :
"Optical recording","Clocks","Magnetic recording","Interference constraints","Channel capacity","Optical signal processing","Magnetic heads","Labeling","Concurrent computing","Magnetic noise"
Journal_Title :
IEEE Transactions on Information Theory