Apparatus and methods for jointly decoding messages based on apriori knowledge of modified codeword transmission

Abstract

A method and apparatus for jointly decoding a first and second message is disclosed. The signaling scenario illustrated by FIG.and using the codeword properties defined herein, the various embodiments may combine multiple messages under the hypothesis that the value of a message portion corresponding any subsequent observed transmission is different. Accordingly a first buffer may store the first observed message frame () and a second buffer may sum the LLR's of subsequent observed frames (). In the embodiments disclosed, two decoding hypotheses are required only; a first where the two buffers are combined directly () and a second where the difference codeword bit LLR's of the first buffer () are inverted before combining with those of the second buffer (). A maximum of N transmissions is allowed by the receiver (), after which a decoding failure is declared.