Block Codes for Energy-Harvesting Sliding-Window Constrained Channels

摘要

Energy-harvesting sliding-window constrained block codes guarantee that within any prescribed window of $ell $ consecutive bits the constrained sequence has at least $t$ , $t geq 1$ , 1’s. Prior art code design methods build upon the finite-state machine description of the $(ell,t)$ constraint, but as the number of states equals $ell $ choose $t$ , a code design becomes prohibitively complex for mounting $ell $ and $t$ . We present a new block code construction that circumvents the enumeration of codewords using a finite-state description of the $(ell,t)$ -constraint. The codewords of the block code are encoded and decoded using a single look-up table. For $(ell =4,t=2)$ , the new block codes are maximal, that is, they have the largest possible number of codewords for its parameters.