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無線網路安全機制剖析

00 02 2d 1d fa c0 00 06 25 ac 24 3c 88 8e 01 00 00 04 01 00 00 04 01 00 00 00 a0 62 fc b9 a1 2c 8c 57 88 9e 0d b3 e7 1e a3 13 00 00 00 00 00 00 00 00 01 d4 60 d5 82 b4 ce 35 59 5a 00 02 2d 1d fa c0eDestination MAC Address 00 06 25 ac 24 3ceSource MAC Address 88 8eePAE Ethernet Type 01eProtocol Version 00 ePacket Type 00 04ePacket Body Length 01eEAP-Packet Code 00eEAP-Identifier 00 04 eEAP-Length 01 eEAP-EAP Type 00 00 00 a0 62 fc b9 a1 2c 8c 57 88 9e 0d b3 e7 1e a3 13 00 00 00 00 00 00 00 00 01 d4 60 d5 82 b4 ce 35 59 5aeEAP-Type Data (2) EAPOL-Start(0x01)e EAPOL-Start,12bytesMAC Address,EAPOL0x888E Ethernet Type 00 06 25 ac 24 3c 00 02 2d 1d fa c0 88 8e 01 01 00 00 00 00 06 25 ac 24 3ceDestination MAC Address 00 02 2d 1d fa c0eSource MAC Address 88 8eePAE Ethernet Type 01eProtocol Version 01ePacket Type(0x01EAP-Start) 00 00ePacket Body Length EAPOL-LogOff(0x02)EAPOL, EAPOL-Key(0x03)Key EAPOL-Encapsulated-ASF-Alert(0x04. […]

WCDMA/UMTS 第三代無線通訊系統 無線技術介紹﹝1﹞

WCDMA/UMTSWCDMAGSM 3GPP R99GSM/GPRSGSM/GPRS3GWCDMAGSM/GPRS Cell Cell : FDMATDMACDMASDMA FDMAFrequency Division Multiple Accesse FDMA FDMA TDMATime Division Multiple Accesse FDMATDMA TDMA Time Slot SDMASpace Division Multiple Accesse SDMASector SDMA SDMASector CDMACode Division Multiple Accesse CDMAorthogonalspreading codes0: 0 CDMAFDMATDMAFDMATDMACDMAFDMATDMA CDMAWCDMAIS-95cdmaOneDS-CDMADirect Sequence-CDMACDMA 2000MC-CDMAMultiCarrier-CDMA DS-CDMAScrambling CodeCellSpreading Code DS-CDMA MC-CDMA MultiCarrier-CDMA GSMGPRSWCDMA GSMGlobal System for Mobile Communication e GSMTDMAFDMAGSM900DownlinkBaseStationUplinkBaseStation GSM 900 GSM 900DownLink935–960MHzUpLink890915MHzUplinkDownlink45MHzFrequency Carrier200 kHz8Time SlotUplinkDownlink GSMAir InterfaceCircuit-Switched GSMFrequency HoppingGSM GSM Frequency Hopping GSMGSM900GSM1800GSM1800 GSM 1800 GSM1800UplinkDownlinkDownLink1805–1880MHzUpLink17101785MHzGSM1800UplinkDownlink95MHz GPRSGeneral Packet Radio Servicee GSMTDMAFDMAGPRSCellGPRS Packet-SwitchedTime-Slot GPRSTime-Slot 4+1GPRS4DownLink1UpLinkGSMGPRSGPRS WCDMAWideband Code Division Multiple Accesse WCDMA 1 DS-WCDMA-FDDDirect Sequence Wideband Code Division Multiple Access Frequency Division DupleseDownLinkUpLink 2 DS-WCDMA-TDD Direct Sequence Wideband Code Division Multiple Access Time Division DupleseDownLinkUpLink 3 MC-CDMA Multi Carrier – Code Division Multiple Accesse CDMAcdmaOne WidebandWCDMA WCDMA-FDDDownLink2110–2170MHzUpLink1920–1980MHzWCDMAChip Rate3.84Mcps3.84MHzGuard Band5MHzWCDMA UplinkDownlink60MHz12UpLinkDownLink5MHz12 WCDMA WCDMA WCDMA DS-WCDMADirect Sequence-WCDMA FDD/TDDFrequency/Time Division Duplex Chip Rate 3.84 Mbps Frame Length 10 ms Carrier Frequeny 5MHz UpLink-Modulation BPSKBinary Phase Shift Keying DownLink-Modulation QPSKQuadrature Phase Shift Keying WCDMASpread SpectrumGSMSpreading Code0 Orthogonal Code (1,1,1,1) (1,1,-1,-1) (1,-1,1,-1) (1,-1,-1,1) (1,1,1,1) 4 0 0 0 (1,1,-1,-1) 0 4 0 0 (1,-1,1,-1) 0 0 4 0 (1,-1,-1,1) 0 0 0 4 Spreading CodeCellWCDMAScrambling CodeScrambling CodeChip Rate3.84MbitCellCellCell DS-WCDMA-FDDUplinkBPSKDownlinkQPSKUplink 1bitSymbol1bitDownload 1bitSymbol2 bitQPSK QPSKe WCDMADownlinkBaseStationQPSK QPSK 1011001111IQI01011Q11011 1I1Q1 2I1Q1 3I0Q0 4I1Q1 5I0Q1 IQIQQPSK IQ Spreading Code8 864 Scrambling CodeQPSKModulationIQ QPSK 01Cosin45 00Cosin315 IQI01010010Q00111101QPSK QPSK QPSKQuadrature Phase Shift KeyingBPSKBinary Phase Shift KeyingBit RateQPSKCosin401QPSKChip Rate Chip Rate 3.84Mbit/secSpreading Factor81bit8bitsBPSK3840(kbit/sec) / 8 = 480 (kbit/sec)QPSK(3840(kbit/sec) / 8)*2 = 960 (kbit/sec) WCDMASpreading CodeChannelChannelisation Code Channelisation CodeChannelisation CodeScrambling CodeChannelisation CodeChannelisation CodeSpreading Factor Spreading Factor = (System Chip Rate) / (User Data Rate) =Channelisation Code Channelisation CodeScrambling Code DownLink UpLink Channelisation Code e (Spreading)Cell eChannel e 512 Chips e 4-256 Chips e (Scrambling Code)Spreading Factor eSpreading Factor Scrambling Code e Cell e e Frame10 ms38400 Chips eFrame10 ms38400 Chips e 512 e WCDMA Frame WCDMAFrame10 msWCDMA3.84 Mbits/secWCDMA Frame3.84 Mbits/sec * 10 ms = 38400 bitsFrame15Time Slot38400 bits /15 = 2560 bits WCDMA Frame UpLinkI-QDual-Channel QPSKDPDCHDPCCHDPDCHDPCCHIBPSKBinary Phase Shift KeyingWCDMA UpLink BPSK UpLink Dual-Channel QPSK UpLink DPDCHDedicated Physical Data ChannelDPCCHDedicated Physical Control ChannelDPDCHDPDCHSpreading Factor4–256DPCCHDPCCHSpreading Factor256DPDCHChannelChannelisation CodeDPDCH DPDCHFrameDPCCHDPCCHTFCITransport Format Combination Indicator WCDMA UpLink Frame UpLinkDownLinkUpLinkDownLinkQPSKDPDCHDPCCHDPDCHChannelisation CodeUpLinkDual-Channel QPSKChannelisationDPDCHDPCCHDownLinkDPDCHDPCCHFrameQPSKChip RateSpreading FactorDownLinkQPSKUpLinkBPSK WCDMA DownLink Frame WCDMAChannel GSM 1800WCDMA-FDD E-Mail:hlchou@mail2000.com.tw […]

10.2M——手機Modem二合一

()21MbpsUSB ModemNokia 6260 slide10.2MbpsHSPA ModemNotebook10.2Mbps ModemNokia6260 slideUSB6260 slideHSPA Modem10.2Mbps2MbpsHSPA6260 slideModem 6260 slideSmartphone10.2Mbps2.4HVGA4803205800XMVGAAV6260 slideGPSS40Nokia MapsFacebookWidSets http://news.sina.com.hk/cgi-bin/nw/show.cgi/86/1/1/1104293/1.html […]