Patent ID: 6307487
Filing Date: 2001-10-23
Classification: H03M,H04L

Abstract:
A method of generating an output symbol, wherein the output symbol is selected from an output alphabet and the output symbol is such that an input file, comprising an ordered plurality of input symbols each selected from an input alphabet, is recoverable from a set of such output symbols, the method comprising the steps of:obtaining a key I for the output symbol, wherein the key is selected from a key alphabet and the number of possible keys in the key alphabet is much larger than the number of input symbols in the input file;calculating, according to a predetermined function of I, a list AL(I) for the output symbol, wherein AL(I) is an indication of W(I) associated input symbols associated with the output symbol, and wherein weights W are positive integers that vary between at least two values and are greater than one for at least one value of I; andgenerating an output symbol value B(I) from a predetermined function of the associated input symbols indicated by AL(I).