迎接數字化通信時代的挑戰(zhàn).ppt

1、迎接數字化通信時代的挑戰(zhàn),一、世界是數字化的,二、數字處理的主要技術,三、“藍牙”技術中的數字通信,鄭國莘,一、世界是數字化的,01101101010100111.,人類基因密碼,無處不在的數字化的技術-計算機,一、世界是數字化的,數字化的通信,Every Thing. Over IP IP Over Every Thing,PSTNCATVINTERNET,迎接數字化通信時代的挑戰(zhàn),一、世界是數字化的,二、數字處理的主要技術,三、“藍牙”技術中的數字通信,知識構架,數學,數據結構,電路、信號與系統(tǒng),通信原理,數字電子,模擬電子,計算機網絡,計算機接口,高頻電子,通信系統(tǒng) 移動通信 微波通信

2、光纖通信,綜合課程,工程實踐課程,理論課程,數字通信系統(tǒng),Coder,Coder,modulation,Demodulation,Decoder,模擬信號的數字化,Coder,Coder,數字信號處理,F,F,-1,微積分 富氏變換 拉氏變換 Z變換 數字信號處理,信源編碼,核心信源編碼有效性編碼 減少份量以降低成本,語音編碼：PCM M LD-CELP MBELP,Hi,how are you!,圖像編碼： JPEG MPEG-1 MPEG-2 MPEG-4,濁音,清音,喉形,MPEG-4視頻編碼原理,MPEG-4的視頻編碼就是針對運動信息、形狀信息和紋理信息 等3種信息的編碼技術,H.26

3、1視頻編碼原理,H.261所針對的可視電話信號最初考慮是在一般電話網中傳 輸的，帶寬和碼率是其考慮的核心問題。,MC 幀差編碼原理,DPCM編碼主要是利用同一幀圖像中各像素之間的相關性 來對當前值進行預測,MPEG2音頻壓縮編碼標準,MPEG2則針對數字電視的視音頻壓縮編碼，對數字電視各種等級的壓縮編碼方案及圖像編碼中劃分的層次作了詳細的規(guī)定，其編碼碼率可從3Mbps到100Mbps。,信道編碼,包裝信道編碼可靠性編碼 增加冗余量以確保安全,奇偶校驗 100100010010001,發(fā)現(xiàn)1位錯誤,重復碼 1111 0000,糾正1位錯誤，發(fā)現(xiàn)2位錯誤,GSMCRC 編碼,信道編碼1,000,1

4、11,許用碼組,禁用碼組,010,100,001,110,101,011,通過增加編碼的位數，以犧牲信息傳輸速率為代價換取 通信的可靠性。,0：come 1: not come,信道編碼2,GSM編碼 15位CRC碼,碼間距,000,111,數字電子技術計算機大廈的磚瓦,1+1=10 A+B=CD,D,向下為1 向上為0,世界萬物,A,B,C,D,空中的數字無線電波,HOWAREYOU!,1001000,1001111,1010111,1000001,.,ASK,FSK,PSK,數字信道的多路復用,TDM 時分復用 FDM 頻分復用 CDMA 碼分多址,光纖,無線電頻譜,F,3*10,3*10

5、,3*10,4,4,5,6,TV,FM,GSM,Bluetooth,Satellite,Visible light,(Hz),高頻電子線路 -數字通信的實現(xiàn),振蕩器 放大器 合成器 天線 微波,IC化,基礎,迎接數字化通信時代的挑戰(zhàn),一、世界是數字化的,二、數字處理的主要技術,三、“藍牙”技術中的數字通信,Bluetooth Introduction,Guoxin Zheng School of Communication and Information Engineering Shanghai University,Architecture Overview,Overview Technic

6、ally Topology Radio/Baseband Protocol stack ModulesEricsson,All (SP,GER, UK, FRA, ITA) - % Distribution by Price segment of Total Sales Volume*(units),1995,Forecast Worldwide Sales 2005,Million units,100,200,300,400,500,600,700,800,900,1000,mobile phones,mobile accessories,portable computers and PDA

7、s,desktop PCs,desktop accessories,printers,cordless phones,telephone answering devices,TV/VCR/DVD,CD-player,Mobile devices,Desktop devices,Consumer electronics,Source: IDC, Strategy Analytics, Ericsson, Silver Institute,Internet connection device,cameras & misc.,Remote control,The Future?,Mobile pho

8、nes is by far the largest segment within Mobile Devices 250 million mobile phones will be sold year 2000 630 million mobile phones will be sold year 2005 Desktop PCs is the largest segment in Desktop Devices 80 million desktop PCs will be sold year 2000 140 million desktop PCs will be sold year 2005

9、 Cordless phones is the largest segment in Consumer Electronics Devices 150 million cordless phones will be sold year 2000 350 million cordless phones will be sold year 2005,Landline,What does Bluetooth do for you?,“Usage Models”,“Design a radio to replace the cable and its connectors”,Design Goals

10、Small implementation size Low implementation cost Low power consumption Secure and robust for open ISM band Challenges Fast frequency hopping Single chip integration,Global Operation,Industrial - Scientific - Medical 80 MHz at 2.45 GHz Globally available Unlicensed and free to use,Unprecedented Cros

11、s Industry Commitment,Special Interest Group Ericsson, IBM, Intel, Nokia and Toshiba And today there are more than 2000 Bluetooth adopters.,Technically Speaking . . .,Bluetooth Module,Small Size 0.5 square inches in production Eventually moving to a single chip solution Low power 2.7V (1.62 - 2.75V)

12、 300 A standby, 30 A in sleep, 60 A hold/park 3 - 30 mA when transmitting 1 or 100 mW active power Low Price $25 projected to come down to around $5 OEM integration cost Designed for CMOS single chip solution,Bluetooth Radio,Bluetooth,Bluetooth Link Controller,Technical Features,2.4 GHz ISM Open ban

13、d Globally free available frequency, 89 MHz of spectrum available FFH/DS Hybrid Radio 10 -100 m range, personal bubble 8 active devices per piconet (share datarate) Up to 10 piconets in bubble (full datarate) 1 Mbps gross rate Future version: 2 Mbps Simultaneous voice/data capable 432 Kbps (full dup

14、lex), 721/56 Kbps (asymmetric) or 3 simultaneous full duplex voice per piconet (CVSD64 Kbps). or a combination of data and voice,Battery Life Time,Estimates calculated with 600 mAh battery and internal amplifier, power will vary with implementation and application Low power consumption Standby curre

15、nt 0.3 mA 3 months Voice mode 10 mA (one voice channel) 60 hours Data mode average 6 mA (20% utilization) 100 hours Low Power Architecture Programmable data length (else radio sleeps) Hold and Park modes 60 A Devices connected but not participating Device can participate within 2 ms,Robust Data and

16、Voice Transfer,Bluetooth is designed to be robust Open band interference is negotiated by: 1600 frequency hops/s Short and flexible data packets Automatic Repeat reQuest (ARQ) Forward Error Correction (FEC) 16 bit Cyclic Redundancy Check Speech coding: Continuos Variable Slope Delta modulation (CVSD

17、),Bluetooth Scalable Security,Provides link layer security between any two Bluetooth radios Authentication (E1 algorithm) Challenge/Response system Encryption (privacy) Encrypts data between two devices Stream cipher with E0 algorithm Key management and usage Configurable Encryption key length (0-16

18、 bytes) Government export regulations Radio negotiate key size Key generation with E2-E3 algorithms Authentication and Encryption keys,Topology,Radio range has two varieties Short range (10 meters or less) 0 dBm radio, 1mW Optimized for short range devices Headset, Mouse, Keyboard, etc. . Longer ran

19、ge (100 meters or less) 20 dBm radio, 100 mW Module has a power amplifier built-in Optimized for devices changing environments Notebooks, cellphones, access points, etc. ,Topology,Radio/Baseband Master/Slave medium access Radio/Baseband is symmetric Connected devices can be master or slave Could be

20、master and slave concurrently,Piconet All devices in a piconet hop together Frequency hopping sequence is determined by the masters ID Phase of the frequency hopping sequence is determined by the masters clock,Topology,Piconet Point to Point Point to Multipoint No base station is needed 8 concurrent

21、 devices More than 200 active devices 1 Mb/s gross rate,Topology,Scatternet Devices can share piconets Interpiconet communication Instant Ad-hoc connections 10 Piconets Aggregated 10 Mb/s,Topology,Mobile Topology All device are mobile Walknet: The whole piconet cell is mobile Make and Brake Connecti

22、ons,Topology,Topology, Scatternet,master,slave 1,slave 2,slave 3,master,slave 4,slave 5,Frequency Hopping,Connection Procedure,Standby Waiting to join a piconet Inquire Finding devices Page Connect to a known device Connected Actively on a piconet (master or slave) Park/Hold Low Power connected stat

23、es,Page and Inquire Scans,A radio must be enabled to accept pages or inquires (also in connected state),Bluetooth Protocol Stack,Control,RFComm,HID,TCP/IP,Still Image,Obex,vCard,WAP,vCal,Basic,Provided,Adapted,Application Framework,Radio,Baseband,Link Man.,L2CAP,Audio,HCI,Ericsson Bluetooth CoreFunc

24、tional Partitioning,Filters and baluns integrated into LTCC substrate RF IC flip chip mounted Laser trimming used to optimize performance 100mW optional version with PA and Optional Gain Control (- 30 to +20 dBm) Small outline BGA type package 1mW: 10.2 x 14 x 1.6 mm 100mW: 10.2 x 16 x 1.6 mm,Radio Module,First Complete Module,Radio,Link Controller,(Optional),Flash,Host interface USB UART/PCM,PA,Antenna,First Complete Module,Key Features FCC type approved Interface through USB, UART or PCM Bluetooth 1.0 pre-certified USB 1.1 compliant (Voice and Data) Small size, 33x17x3.36 mm Generic