Integer multiple mark modulation (IMMM) using binary asymmetrical runlength limited sequences

A new modulation coding technique, called integer multiple mark modulation (IMMM) is proposed. IMMM codes generate asymmetrical runlength limited (RLL) sequences with spectral nulls in the power spectrum, whose positions are related to a specific runlength constraint. This coding technique can be used for any channel requiring specific spectral nulls in the code spectrum, such as partial-response optical recording. We present a few new propositions that can be of assistance in developing new codes. The characteristic equation used for calculating the channel capacity and a closed form expression for the power spectrum of maxentropic IMMM sequences are presented. A generating function for determining the maximum number of concatenable codewords which is useful for developing block codes, is also given. Finally, a new block code is developed to illustrate the use of the IMMM coding technique