Design Of Virtual Radio Receiver Sub-system And Research Of The Signal Identification Algorithm

Sincetheconceptofsoftwareradiohasbeenputforward,nomatterinmilitaryorcivilian,softwareradiohasbecomearesearchwhichfocusoncommunicationfield.Asabranchofsoftwareradio,virtualradiosystemsimplementthesignalprocessingbycomputers.DependinguponhighperformanceofADC,virtualradiosystemsconverttheanalogsignalintodigitalsignal,transmitthemthroughPCIbus,andthenperformallofdigitalsignalprocessingonacomputer,whichmakesthesystemmoreflexible.In this thesis, the design of the virtual radio receiver sub-system and theidentification algorithm of MQAM signal are studied. The system of A/D conversionand the CPLD logic control module are introduced in detail as well as the realizationandfunctionofPCI.TheDMAmethodisadoptedinthisthesistoachieveahigh-speedfor data transmission.Under the circumstance of windows 2000, the PCI equipmentdrive and user applied programmer is also exploited. Meanwhile, the signalidentification of MQAM signal is mentioned in this thesis. In the process ofclassification,findingout carrierfrequencyofreceivedsignal,detectionof symbolrateand realization of the bit synchronization are carried out. And then, classify MQAMsignal based on amplitude statistical moments. Even when some errors of bitsynchronizationexist,themethodputforwardinthisthesisisvalid.