AMathematicalTheoryofCommunicationByC.E.SHANNONINTRODUCTIONTHErecentdevelopmentofvariousmethodsofmodulationsuchasPCMandPPMwhichexchangebandwidthforsignal-to-noiseratiohasintensifiedtheinterestinageneraltheoryofcommunication.AbasisforsuchatheoryiscontainedintheimportantpapersofNyqui