Patent ID: 6362757
Filing Date: 2002-03-26
Classification: H03M

Abstract:
A coding method for converting m-bit input data into an n-bit codeword, comprising:selecting the number of input bits m and the number of output bits n for an (m,n) block code; accumulating a sufficient number of BUDA (binary unit DSV and ASV) cells to form a BUDA stack for derivation of a state diagram; picking one node as a state, and securing at least 2m exit paths of an n-hop length, and denoting each terminating node of each path as another state; starting with a new state and repeating the previous step; if it turns out that the stack needs to be expanded to complete the state diagram, adding more cells to the stack either horizontally or vertically as appropriate; reducing the number of states as possible with all transition paths terminating on one of the arranged states; at each state, arranging the mapping table as an input m-bit combination to an output n-bit combination; and, as necessary, plotting the power spectrum of the coded sequence with varying input bit probability, and choosing the mapping that would generate the most desirable power spectral properties.