迎接数字化通信时代的挑战.ppt

1、迎接数字化通信时代的挑战,一、世界是数字化的,二、数字处理的主要技术,三、“蓝牙”技术中的数字通信,郑国莘,一、世界是数字化的,01101101010100111.,人类基因密码,无处不在的数字化的技术-计算机,一、世界是数字化的,数字化的通信,Every Thing. Over IP IP Over Every Thing,PSTNCATVINTERNET,迎接数字化通信时代的挑战,一、世界是数字化的,二、数字处理的主要技术,三、“蓝牙”技术中的数字通信,知识构架,数学,数据结构,电路、信号与系统,通信原理,数字电子,模拟电子,计算机网络,计算机接口,高频电子,通信系统 移动通信 微波通信

2、光纤通信,综合课程,工程实践课程,理论课程,数字通信系统,Coder,Coder,modulation,Demodulation,Decoder,模拟信号的数字化,Coder,Coder,数字信号处理,F,F,-1,微积分 富氏变换 拉氏变换 Z变换 数字信号处理,信源编码,核心信源编码有效性编码 减少份量以降低成本,语音编码：PCM M LD-CELP MBELP,Hi,how are you!,图像编码： JPEG MPEG-1 MPEG-2 MPEG-4,浊音,清音,喉形,MPEG-4视频编码原理,MPEG-4的视频编码就是针对运动信息、形状信息和纹理信息 等3种信息的编码技术,H.26

3、1视频编码原理,H.261所针对的可视电话信号最初考虑是在一般电话网中传 输的，带宽和码率是其考虑的核心问题。,MC 帧差编码原理,DPCM编码主要是利用同一帧图像中各像素之间的相关性 来对当前值进行预测,MPEG2音频压缩编码标准,MPEG2则针对数字电视的视音频压缩编码，对数字电视各种等级的压缩编码方案及图像编码中划分的层次作了详细的规定，其编码码率可从3Mbps到100Mbps。,信道编码,包装信道编码可靠性编码 增加冗余量以确保安全,奇偶校验 100100010010001,发现1位错误,重复码 1111 0000,纠正1位错误，发现2位错误,GSMCRC 编码,信道编码1,000,1

4、11,许用码组,禁用码组,010,100,001,110,101,011,通过增加编码的位数，以牺牲信息传输速率为代价换取 通信的可靠性。,0：come 1: not come,信道编码2,GSM编码 15位CRC码,码间距,000,111,数字电子技术计算机大厦的砖瓦,1+1=10 A+B=CD,D,向下为1 向上为0,世界万物,A,B,C,D,空中的数字无线电波,HOWAREYOU!,1001000,1001111,1010111,1000001,.,ASK,FSK,PSK,数字信道的多路复用,TDM 时分复用 FDM 频分复用 CDMA 码分多址,光纤,无线电频谱,F,3*10,3*10

5、,3*10,4,4,5,6,TV,FM,GSM,Bluetooth,Satellite,Visible light,(Hz),高频电子线路 -数字通信的实现,振荡器 放大器 合成器 天线 微波,IC化,基础,迎接数字化通信时代的挑战,一、世界是数字化的,二、数字处理的主要技术,三、“蓝牙”技术中的数字通信,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