Signal processing method

Abstract

A signal method of processing in a receiver a signal that has been encoded and interleaved in a transmitter comprising: receiving a signal, process the signal to obtain a stream of soft metrics representing bit probability of symbols in a predetermined constellation; applying to said soft metric a compression operation that preserves the total length of each group of soft metrics relative to a same constellation symbol; rearranging the stream of compressed soft metrics so as to inverse the interleaving done in the transmitter.

1 . A method of compressing a stream of fixed-point representations of soft metrics in a receiver, comprising
 demultiplexing the soft metrics so as to obtain a plurality sub-streams having distinct statistics distributions.   applying to each sub-stream an entropy code adapted to its statistic distribution.   
     
     
         2 . The method of  claim 1 , further comprising
 reconstruct a transmitted message according to each of the sub-stream which is applied with the entropy code adapted to its statistic distribution.   
     
     
         3 . The method of  claim 1 , comprising a step of quantizing the soft metrics prior to the step of demultiplexing the soft metrics. 
     
     
         4 . The method of  claim 1 , wherein said soft metrics are represented as fixed-point numbers. 
     
     
         5 . The method of  claim 3 , wherein the quantizing operation generates a constant number of bits for each group of soft metrics relative to a same constellation symbol. 
     
     
         6 . The method of  claim 3 , wherein the quantizing operation generates different number of bits for each soft metric relative to a same constellation symbol.