《Orthogonal M-ary code shift keying spread spectrum underwater acoustic communication》.pdf

、 1．33NO．3 CHINESE JOURNAL 0FACOUSTICS 2014 OrthogonalM -ary codeshift keying spread spectrum underwateracousticcom munication术 YUYang ZHOUFeng QIAOGang NIEDonghu。 (1 ScienceandTechnologyonUnderwaterAcousticLaboratory， HarbinEngineeringUniversity Harbin 150001) (2 CollegeofComputerScienceandTechnology，HarbinEngineeringUniversity Harbin 150001) ReceivedApr14，2013 RevisedM ar．3，2014 Abstract M—aryandcodeshiftkeying(CSK)spreadspectrum isgenerallyappliedtoover— comingthespreadinggainversusdataratelimitationinunderwateracoustic(U、vA)communi— cations．In addition．theconceptoforthogonalM ．aryCSK iSintroducedtoUWA communica- tiontogainhigherrates．W eproposeaschemeemployingdual_orth0gonal—channelM—aryand CSK spreadspectrum communicationbasedonGoldsequencesowinglargecodesetand goodselfandcrosscorrelation．Themodulation anddemodulation schemeoftheorthogonal M—aryCSK iSderivedalgebraicallyandthefactorscriticaltoitsperformancearediscussed． Furthermore，itsbiterrorrate(BER1curveiSevaluatedviasimulationsandcomparedwiththe dual—channelM—aryCSK．Finally．thevalidityofthesimulationsiSverifiedintankexperiments． 1096．8bpsdatarateoftheproposedcommunicationschemeisrealizedfor10kbitsdatavolume with noerror．Overallthroughdeduction．numericalsimulation．andexperiment．itiSshown thattheproposedmethodofferssignificantlyimprovedperformance． PACS numbers：43．30 1 Introduction Spreadspectrum communicationownsstronganti．．noiseandanti．．fadingcapabilitiesWhich fitthedetrimentaltransmissionconditionssuchastimevariance，Kequencyvarianceandspace varianceoftheunderwateracoustic(UWA)channels．Duetothelowdatarateandpoor security，conventionaldirectsequencespreadspectrum (DSSS)can’tmeettheincreasingneed ofthesociety．Inrecentyears，somenew techniqueshaveemerged suchas