数字电视基础培训.ppt
1,数字电视基础培训 Part 1,有线所2005-09,Confidential,2,内容,数字与模拟图像压缩数字调制基础数字电视标准数字电视传输体系数字电视服务体系小结参考文献,Confidential,3,数字与模拟,Confidential,4,图像压缩,为什么要进行压缩编码数字复合NTSC:143Mbps 数字复合PAL:177Mbps数字分量ITU-R 601:270Mbps,Confidential,5,图像压缩,Confidential,6,图像压缩,压缩标准：JPEG：Joint Picture Experts Group Motion-JPEGMPEG：Moving Picture Experts Group MPEG-1 MPEG-2 MPEG-3 MPEG-4,Confidential,9,图像压缩,Confidential,10,图像压缩,1,2,3,4,5,6,7,8,9,10,11,12,13,I1,P4,B2,B3,P7,B5,B6,P10,B8,B9,I13,B11,B12,1,2,3,4,5,6,7,8,9,10,11,12,13,Confidential,11,图像压缩,Confidential,12,图像压缩,Confidential,13,图像压缩,Confidential,14,数字调制基础,信源编码的目的是提高信源的效率信道编码的目的是增加传输的可靠性透明，对所传信息的内容没有任何限定具有与信道相适应的频谱特征效率高包含同步信息有纠错能力差错扩散度低,Confidential,15,数字调制基础,0000,0001,0010,0011,0100,0101,0110,0111,1000,1001,1010,1011,1100,1101,1110,1111,Confidential,16,数字调制基础,Confidential,17,数字调制基础,0000-0011-1001-1111-1100-0111-0101-1000-0110-0010-0100,0000,0011,1001,1111,1100,0111,0101,1000,0110,0010,0100,需要VLC等对数据的优化,Confidential,18,数字电视标准,AV信源,AV编码压缩,码流复用,信道编码调制,信道解调解码,AV解码,AV显示,Confidential,19,数字电视标准,欧洲：DVB美国：ATSC日本：ISDB-T,Confidential,20,数字电视传输体系,有线信道数字有线电视无线信道数字卫星电视数字地面电视数字手持电视,Confidential,21,数字电视传输体系数字有线电视,16QAM,32QAM,64QAM,128QAM,256QAM,Confidential,22,数字电视传输体系数字卫星电视,Confidential,23,数字电视传输体系数字地面电视,调制方式：COFDM Coded Orthogonal Frequency Division Multiplex2K：17058K：6817,Confidential,24,数字电视传输体系数字地面电视,Confidential,25,数字电视传输体系数字手持电视,Based on DVB-T,backwards fully compatibleGives additional features to support Handheld portable and mobile receptionbattery saving mobility with high data rates,single antenna reception,SFN networksimpulse noise toleranceincreased general robustnesssupport for seamless handoverThe above have been achieved by adding optionsTime-slicing for power savingMPE-FEC for additional robustness and mobility4k mode for mobility and network design flexibilityplus additional minor changes,e.g.,in signallingDVB-H is meant for IP-based services via MPE insertionDVB-H can share DVB-T multiplex with MPEG2 servicesPortable/indoor coverage should be built to the network for fully exploit the DVB-H possibilities businesswise,Confidential,26,数字电视传输体系数字手持电视,DVB-H,Powerconsumptionis key!,H,Confidential,27,数字电视传输体系数字手持电视,Based on DVB-T,can share multiplex with DVB-T servicesIP-based solution,MPE used over DVB-TNew 1:Time Slicing for power savingNew 2:MPE-FEC for mobile performance and tolerance to impulse noise,(reuses memory of time slicing,has effectively a virtual time interleaver)New 3:features to DVB-T PHYOptional 4K mode and 4K symbol interleaver for mobility in large and medium sized SFNsOptional in-depth interleaver for 2K and 4KAdditional signalling in TPSMandatory use of cell-ID5 MHz channels for non-broadcasting bands,Confidential,28,数字电视传输体系数字手持电视,MUX,8k,4k,2k,DVB-H TPS,DVB-T Modulator,TS,RF,RF,Transmitter,8k,4k,2k,DVB-H TPS,DVB-T Demodulator,TS,Receiver,Channel,Confidential,29,数字电视传输体系数字手持电视,Time Sliced and non-Time Sliced services in common multiplexOnly receiver switched off,transmitter on all the timeSupport for Time Slicing not mandatory to receive Time Sliced serviceEven 90%power saving for the front-end can easily be achieved.Uninterrupted service reception with single receiver hand-over.,e.g.MPEG2,Confidential,30,数字电视传输体系数字手持电视,Confidential,31,数字电视服务体系,Confidential,32,数字电视服务体系,Confidential,33,数字电视服务体系,Confidential,34,数字电视服务体系,Confidential,35,数字电视服务体系,Confidential,36,数字电视服务体系,Confidential,37,数字电视服务体系,Confidential,38,数字电视服务体系,数据广播,Confidential,39,数字电视服务体系,应 用,MPEG-2 TS 流,数据管道,数据流,PES,MPEG-2 私有数据段,DSM-CCSection,DSM-CC数据轮播,DSM-CC对象轮播,对象轮播,多协议封装,数据轮播,Confidential,40,数字电视服务体系,Confidential,41,数字电视服务体系,Confidential,42,小结,数字电视的系统性数字电视的综合性数字电视的复杂性,Confidential,43,参考文献,DVB-7.0ISO 13818DiviCom、Alticast、DVB演示文档,Confidential,44,Confidential,
