What is DVB virtual currency
Publish: 2021-04-29 05:28:22
1. In the field of digital video broadcasting (DVB), Europe is the first to carry out research and standard formulation. Its established digital TV broadcasting standard is supported by ITU (International Telecommunication Union) International Telecommunication Union. The standard includes DVB-S, DVB-C and DVB-T, which are applicable to satellite TV, cable TV and terrestrial TV broadcasting respectively, It has been approved by European Telecommunication Standard (ETS), and has been adopted by many countries and regions outside Europe to carry out commercial broadcasting in accordance with DVB standard (dvb-smatv, dvb-ms, dvb-mc and DVB-H)<
at present, the three main terrestrial digital TV standards in the world are: ATSC in the United States, which adopts single carrier technology; Japanese ISDB-T standard (orthogonal frequency division multiplexing) OFDM orthogonal frequency division multiplexing technology and European DVB-T standard adopt coded orthogonal frequency division multiplexing (COFDM) coding orthogonal frequency division multiplexing technology
in addition to the advantages of high definition of image, high fidelity of accompanying sound and large number of programs, digital TV can also provide data transmission service and realize the digital interactive function, namely digital VOD (video on demand).
at present, the three main terrestrial digital TV standards in the world are: ATSC in the United States, which adopts single carrier technology; Japanese ISDB-T standard (orthogonal frequency division multiplexing) OFDM orthogonal frequency division multiplexing technology and European DVB-T standard adopt coded orthogonal frequency division multiplexing (COFDM) coding orthogonal frequency division multiplexing technology
in addition to the advantages of high definition of image, high fidelity of accompanying sound and large number of programs, digital TV can also provide data transmission service and realize the digital interactive function, namely digital VOD (video on demand).
2. DVB-T is the standard of digital terrestrial television broadcasting system. This is the most complex DVB transmission system. The transmission capacity of DTT transmission is equivalent to that of CATV system in theory, and the coverage of this area is good. DVB-T Digital TV system uses a lot of bus TV, subway, buildings, taxis, car top, is the best solution to watch TV programs on the car. So we usually call it: mobile digital TV
the most important feature of DVB-T is that TV programs are high-definition and can be received without interruption when the car is driving at high speed. This is the traditional analog signal TV does not have. It can be said that the shortcomings of analog TV are perfectly solved by dvb-t
DVB-C standard is adopted by digital cable TV in home, which is totally different from dvb-t. Please don't confuse
how many DVB-T Digital TV stations can receive depends on how many DVB-T channels the local TV stations can turn on. For example, we can receive 7 stations in Guangzhou and 3 stations in Shenzhen. Please note: is DVB-T the same as home TV. So your home can receive dozens of programs, while DVB-T Digital TV can only receive a few. This is not the problem of TV box reception, it is that your local DVB-T channels are too few. Similarly, the content of TV programs received also depends on the TV station. Most cities' DVB-T TV programs are mainly traffic, tourism, entertainment, news and other programs
to watch DVB-T TV programs, you need to have a DVB-T system in your local area. Now the provinces and cities that adopt this system standard are:
Guangdong Province (Guangzhou, Foshan, Shenzhen), Beijing, Shanghai, Changsha, Nanjing, Chongqing, Zhengzhou, Dalian, Jinan, Hangzhou, Wuhan, Hefei, Lanzhou, Nanjing and most other cities.
the most important feature of DVB-T is that TV programs are high-definition and can be received without interruption when the car is driving at high speed. This is the traditional analog signal TV does not have. It can be said that the shortcomings of analog TV are perfectly solved by dvb-t
DVB-C standard is adopted by digital cable TV in home, which is totally different from dvb-t. Please don't confuse
how many DVB-T Digital TV stations can receive depends on how many DVB-T channels the local TV stations can turn on. For example, we can receive 7 stations in Guangzhou and 3 stations in Shenzhen. Please note: is DVB-T the same as home TV. So your home can receive dozens of programs, while DVB-T Digital TV can only receive a few. This is not the problem of TV box reception, it is that your local DVB-T channels are too few. Similarly, the content of TV programs received also depends on the TV station. Most cities' DVB-T TV programs are mainly traffic, tourism, entertainment, news and other programs
to watch DVB-T TV programs, you need to have a DVB-T system in your local area. Now the provinces and cities that adopt this system standard are:
Guangdong Province (Guangzhou, Foshan, Shenzhen), Beijing, Shanghai, Changsha, Nanjing, Chongqing, Zhengzhou, Dalian, Jinan, Hangzhou, Wuhan, Hefei, Lanzhou, Nanjing and most other cities.
3.
DTMB, also known as DMB-T, is different from DVB in the following aspects:
1. Different in nature
1. DTMB is the TV standard used by mobile and fixed terminals
DVB is a set of internationally recognized open standard digital TVtwo, the different uses of
1, DTMB: in Chinese mainland, Hongkong and Macao. p>
2. DVB: it is international and can be used by countries with more than 270 members
DTMB: the information transmission bit rate of effective payload of each channel can be as high as 33MB / s under the bandwidth of 8MHz DVB: a hybrid network with unidirectional broadcast network4. A: DVB-C
is a limited receiver
; DVB-T
is a terrestrial wireless receiver
DVB (Digital
Video
broadcasting) refers to the broadcasting of "data container" which can transmit all types of data. Advanced applications of DVB technology include multimedia data broadcasting, Internet over the air transmission, interactive broadcasting service and application in mobile communication combined with GPRS technology DVB-S (DVB-S
and
DVB-S2) are satellite digital receivers DVB-H)
is a handheld ground wireless receiver.
is a limited receiver
; DVB-T
is a terrestrial wireless receiver
DVB (Digital
Video
broadcasting) refers to the broadcasting of "data container" which can transmit all types of data. Advanced applications of DVB technology include multimedia data broadcasting, Internet over the air transmission, interactive broadcasting service and application in mobile communication combined with GPRS technology DVB-S (DVB-S
and
DVB-S2) are satellite digital receivers DVB-H)
is a handheld ground wireless receiver.
5. DVB Digital Video Broadcast是数字电视标准
6. As a new generation of digital satellite broadcasting standard, dvb-s.2 is about to be issued, and the draft has been officially released. The new standard not only improves the transmission capacity of the original channel, but also greatly expands the business scope, which has been widely concerned in the fields of radio and television, telecommunications, computer and so on. Based on the comparison with the previous standards, this paper expounds the main advantages of the new standard technology, and briefly introces the research and development background, current progress and future application prospects of the standard
7. DVB is a kind of digital video broadcasting and ASI is one of the transmission modes, which is asynchronous serial interface
8. 1. The core of DVB standard:
(1) the system uses MPEG-2 compressed audio, video and data formats as resources
(2) the system adopts public MPEG-2 transmission (TS) multiplexing mode
(3) the system uses common system service information (SI) to describe broadcast programs
(4) the first stage channel coding of the system adopts R-S forward error correction coding protection
(5) molation and other auxiliary channel coding methods are determined by different transmission media; General scrambling method and conditional access interface are used< DVB transmission system is divided into two parts: source coding and channel coding. MPEG-2 code stream is used in source coding. Firstly, audio and video are multiplexed, and then multiple DTV program streams are multiplexed. The corresponding demultiplexing and decoding are carried out at the receiving end
channel coding and decoding includes three parts: forward error correction coding, decoding, molation, demolation and up and down conversion. QPSK (4-phase shift keying) is used for satellite transmission, QAM (quadrature amplitude molation) is used for cable transmission, and COFDM (coded orthogonal frequency division multiplexing) or 16vsb (16 level resial sideband molation) is used for ground transmission< (1) dvb-s-digital satellite live broadcasting system standard: digital satellite transmission system is designed to meet the bandwidth of satellite transponder and the transmission characteristics of satellite signal. The standard uses satellite as transmission medium. The video, audio and data are put into the MPEG-2 transport stream with fixed length package. The signal has strong anti-interference ability in the process of transmission, and then the channel processing is carried out. The compressed digital signal transmitted by the satellite is processed by the satellite set-top box after passing through the satellite receiver, and the video signal is output. This kind of transmission covers a wide range and has a large number of programs. Four phase shift keying (QPSK) is used in the data stream MP@ML (main class @ main level) format, the bit rate of ccir601 studio quality is 9mb / s, and the bit rate of PAL quality is 5MB / s. After the publication of DVB-S standard, almost all satellite live digital TV adopt this standard, and China also adopts DVB-S standard< (2) DVB-C digital cable broadcasting system standard: the standard uses cable TV network as the transmission medium and has a wide range of applications. CATV system is divided into two parts: CATV front end and integrated decoding receiver (IRD). Because the transmission medium of MPEG-2 compressed coding is coaxial cable, compared with satellite transmission, it has strong anti-interference ability and relatively high signal strength. There are 16, 32 and 64 QAM molation modes. For QAM molation, the higher the information transmission rate is, the lower the anti-interference ability is. When 64QAM quadrature amplitude molation is used, the transmission rate of one pal channel is 41.34mb/s, and it can be used for multiple programs. DVB-C transmission system has the following main characteristics: A. It can adapt to a variety of program sources. The programs transmitted by DVB-C transmission system can come from the programs received from satellite system, local TV programs and other foreign program signals; B. It can be used in both standard digital TV and HDTV< (3) DVB-T Digital Terrestrial Broadcasting System Standard: this system standard was passed in 1998, which is the most complex DVB transmission system. Without coding orthogonal frequency division multiplexing (COFDM) molation, four TV programs can be transmitted within 8MHz bandwidth with high transmission quality. MPEG-2 digital video and audio compression coding technology is adopted. Theoretically, the transmission capacity of terrestrial digital transmission is as large as that of cable TV system, and the local coverage is good. This system is concive to the coexistence of digital and analog TV, and shows advantages in hybrid transmission with current analog TV. DVB-T standard mainly specifies the system structure and signal processing mode of the transmitter, while it is open to the receiver. Manufacturers can develop their own DVB-T receiving equipment, as long as the equipment can correctly receive and process the transmitted signal and meet the performance index specified in dvb-t< (4) dvb-smatv digital SMATV broadcasting system standard: this standard is based on DVB-S and DVB-C
(5) the standard of digital broadcasting MMDS distribution system with dvb-ms higher than 10GHz: MMDS is a system that uses am microwave to transmit to multipoint and distribute multi-channel TV programs. The system is based on DVB-S, which makes the microwave signal carrying a large number of programs directly into the home. Dvb-ms signal can be received by DVB-S receiver with a MMDS frequency switch< (6) the standard of digital broadcasting MMDS distribution system with dvb-mc lower than 10GHz
this standard is based on DVB-C, which makes the microwave signal carrying a large number of programs directly into the home. Dvb-mc signal can be received by DVB-C receiver with a MMDS frequency converter< Many services in DVB digital broadcasting system can provide various forms of interactive services according to the needs. On the basis of the general DVB digital broadcasting system, the elements of the interactive service system further include the independent protocol of the interactive service network compatible with other relevant international standards, the return channel for transmitting the command and control signals of the interactive service process, etc. The corresponding interactive service system DVB standards are:
dvb-nip-interactive service network independent protocol standard
DVB retransmission channel standard of dvb-rcc-catv system
DVB retransmission channel standard of dvb-rct-pstn / ISDN
(1) the system uses MPEG-2 compressed audio, video and data formats as resources
(2) the system adopts public MPEG-2 transmission (TS) multiplexing mode
(3) the system uses common system service information (SI) to describe broadcast programs
(4) the first stage channel coding of the system adopts R-S forward error correction coding protection
(5) molation and other auxiliary channel coding methods are determined by different transmission media; General scrambling method and conditional access interface are used< DVB transmission system is divided into two parts: source coding and channel coding. MPEG-2 code stream is used in source coding. Firstly, audio and video are multiplexed, and then multiple DTV program streams are multiplexed. The corresponding demultiplexing and decoding are carried out at the receiving end
channel coding and decoding includes three parts: forward error correction coding, decoding, molation, demolation and up and down conversion. QPSK (4-phase shift keying) is used for satellite transmission, QAM (quadrature amplitude molation) is used for cable transmission, and COFDM (coded orthogonal frequency division multiplexing) or 16vsb (16 level resial sideband molation) is used for ground transmission< (1) dvb-s-digital satellite live broadcasting system standard: digital satellite transmission system is designed to meet the bandwidth of satellite transponder and the transmission characteristics of satellite signal. The standard uses satellite as transmission medium. The video, audio and data are put into the MPEG-2 transport stream with fixed length package. The signal has strong anti-interference ability in the process of transmission, and then the channel processing is carried out. The compressed digital signal transmitted by the satellite is processed by the satellite set-top box after passing through the satellite receiver, and the video signal is output. This kind of transmission covers a wide range and has a large number of programs. Four phase shift keying (QPSK) is used in the data stream MP@ML (main class @ main level) format, the bit rate of ccir601 studio quality is 9mb / s, and the bit rate of PAL quality is 5MB / s. After the publication of DVB-S standard, almost all satellite live digital TV adopt this standard, and China also adopts DVB-S standard< (2) DVB-C digital cable broadcasting system standard: the standard uses cable TV network as the transmission medium and has a wide range of applications. CATV system is divided into two parts: CATV front end and integrated decoding receiver (IRD). Because the transmission medium of MPEG-2 compressed coding is coaxial cable, compared with satellite transmission, it has strong anti-interference ability and relatively high signal strength. There are 16, 32 and 64 QAM molation modes. For QAM molation, the higher the information transmission rate is, the lower the anti-interference ability is. When 64QAM quadrature amplitude molation is used, the transmission rate of one pal channel is 41.34mb/s, and it can be used for multiple programs. DVB-C transmission system has the following main characteristics: A. It can adapt to a variety of program sources. The programs transmitted by DVB-C transmission system can come from the programs received from satellite system, local TV programs and other foreign program signals; B. It can be used in both standard digital TV and HDTV< (3) DVB-T Digital Terrestrial Broadcasting System Standard: this system standard was passed in 1998, which is the most complex DVB transmission system. Without coding orthogonal frequency division multiplexing (COFDM) molation, four TV programs can be transmitted within 8MHz bandwidth with high transmission quality. MPEG-2 digital video and audio compression coding technology is adopted. Theoretically, the transmission capacity of terrestrial digital transmission is as large as that of cable TV system, and the local coverage is good. This system is concive to the coexistence of digital and analog TV, and shows advantages in hybrid transmission with current analog TV. DVB-T standard mainly specifies the system structure and signal processing mode of the transmitter, while it is open to the receiver. Manufacturers can develop their own DVB-T receiving equipment, as long as the equipment can correctly receive and process the transmitted signal and meet the performance index specified in dvb-t< (4) dvb-smatv digital SMATV broadcasting system standard: this standard is based on DVB-S and DVB-C
(5) the standard of digital broadcasting MMDS distribution system with dvb-ms higher than 10GHz: MMDS is a system that uses am microwave to transmit to multipoint and distribute multi-channel TV programs. The system is based on DVB-S, which makes the microwave signal carrying a large number of programs directly into the home. Dvb-ms signal can be received by DVB-S receiver with a MMDS frequency switch< (6) the standard of digital broadcasting MMDS distribution system with dvb-mc lower than 10GHz
this standard is based on DVB-C, which makes the microwave signal carrying a large number of programs directly into the home. Dvb-mc signal can be received by DVB-C receiver with a MMDS frequency converter< Many services in DVB digital broadcasting system can provide various forms of interactive services according to the needs. On the basis of the general DVB digital broadcasting system, the elements of the interactive service system further include the independent protocol of the interactive service network compatible with other relevant international standards, the return channel for transmitting the command and control signals of the interactive service process, etc. The corresponding interactive service system DVB standards are:
dvb-nip-interactive service network independent protocol standard
DVB retransmission channel standard of dvb-rcc-catv system
DVB retransmission channel standard of dvb-rct-pstn / ISDN
9. DVB + Ott is the integration of the three networks of radio and television. Generally speaking, telecommunication network, cable television network and computer network penetrate and are compatible with each other, and graally integrate into a unified information and communication network all over the world. The three intersect with each other, forming a pattern that you have me and I have you. The Internet is its core part.
10. Satellite TV set top box
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