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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 […]

剖析Linux上的kHttpd網頁伺服

int MainDaemon(void *cpu_poing)MainDaemon0MainDaemon1QueueManagement DaemonMainDaemonint WaitForHeaders(CPUNR)(waitqueue_decode.bmp) int WaitForHeaders(CPUNR) 1.Http Request 2.kHttpdUser Mode Web Server int WaitForHeaders(CPUNR) 2DecodeHeader 4~8IsForUserSpace!=0UserspaceQueue 9~12IsForUserSpace==0DataSendingQueue static int DecodeHeader(const int CPUNR, struct http_request *Request) 2http 3URL 4Mime 5~10MimeUser Mode Web ServerIsForUserSpace 11~15URLUser Mode Web ServerIsForUserSpace 16~28kHttpdkHttpd 18~22cache 23~27ClientcacheClientcache (Request)MainDaemonint WaitForHeaders(CPUNR) 1.ClientcacheMainDaemon(stack_send_httpdheader.bmp)Send304()SendBuffer() 2.MainDaemonSendHTTPHeader(Request)HTTPDataSending(CPUNR)SendBuffer_async()(stack_send_httpheader.bmp) 3.MainDaemonint Userspace(const int CPUNR)User Mode Web Server int Userspace(const int CPUNR) 2AddSocketToAcceptQueueUser Mode Web Server 4User Mode Web Server 8~9User Mode Web ServerHttp static int AddSocketToAcceptQueue(struct socket *sock,const int Port) User Mode Web ServerUser Mode Web Server 4.kHttpd key inkHttpd(stop)(MainDaemon.bmp)sysctl_khttpd_stop1MainDaemon0MainDaemon1Management Daemonkey in(unload)(managementdaemon.bmp)Management Daemon 5. […]

Windows 98核心介紹

Windows 95,Andrew Schulman Unauthorized Windows 95 Developers Resource Kit,,Windows,Windows 98,,Windows 98,,,Windows 98Windows NTWindows 2000(NT),,Windows 98,Windows NT Windows 2000 ,Wnidows 98(),, VMM32.VXDLoadVXD,Ring 0,VMM32.VXD,Windows 98(95)Ring 0,VXD,.,VXD(LE),VXD(),,krnl386.exeVMM32.VXDDPMI Client DPMI Server,VMM32.VXDkrnl386.exe( krnl386.exeNE,16-bit),Andrew Schulmancommand.comkrnl386.exe,v86 DOS,Windows 98,WinICE,WindowsDOS V86WinICE,C:\Ctrl+DWinICE,()<Step 1>EXEHDRkrnl386.exe,krnl386.exeKernel,()<Step 2>krnl386.exe,NE,()<Step 3>krnl386.exeEXITKERNEL,krnl386.exeV8616 bit,,Kernel32.dll(Windows System Programming SECRECTS<Matt Pietrek>VWIN32.vxd ,Kernel32.dll,krnl386.exe),Windows 98Shell(system.iniShell = explorer.exe),,.,,Andrew SchulmanWinFile.exeExplorer.exe,Shell,Windows 98(95)Explorer.exe,,,Win 32,,,Win32 () () DriverVXD Service Windows 9820(),()<Step 1> […]