| 1, Introduction TDT signal in the digital video | | | | contrast, in the multi-program transmission, TDT |
| Broadcasting In business information (SI) as the time | | | | signal inserted downstream of the multiplexer is |
| and date table, a mandatory requirement in the | | | | appropriate, and then transmitted through modulation |
| specifications that are part of the basic data that can | | | | and demodulation decoder, remove the TDT signal. |
| not be scrambling for public use. But the question is: | | | | The basic structure of the whole process shown in |
| TDT signal how to import and export? The time | | | | Figure 1. Mainly consists of importing, exporting, |
| variation of that? Time to get more useful | | | | testing three parts, all related to hardware and |
| information and what kind of import and export | | | | software innovation and development, as described |
| mode? Not previously available literature references. | | | | below. |
| Electronic Program Guide EPG as important as the | | | | Figure 1 (1) TDT signal into TDT signal can |
| information had the same experience for a long time | | | | generate a lot of digital video equipment, but few |
| indifferent, TDT signal although a similar experience, | | | | have a separate set of standard time signals into |
| but the central TV station Science and technology | | | | interfaces. After repeated experiments, confirm the |
| workers and the efforts of scientists in Qingdao, on | | | | time with digital video equipment, much of the |
| the TDT signal is no doubt accelerate the | | | | information is from the operating system or CPU |
| development of its application process was | | | | clock circuit on the motherboard, and the clock circuit |
| welcomed by all. | | | | of the time and date information is usually entered |
| Should be made clear is that we use Test Methods | | | | manually by keyboard, and self-running large |
| and the formation of the test were no published | | | | accumulation of errors. In foreign countries on the |
| data, hoping to start a discussion. | | | | motherboard CPU clock time calibration of equipment, |
| 2, TDT signals, the meaning and application of results | | | | use convenient, and each device-one configuration, |
| Digital video broadcasting business information (SI) | | | | can not be shared. |
| data to help users stream selected from the business | | | | When we design a new code change and Distributor |
| and / or event information, so integrated receiver | | | | , According to CCTV engine room master clock |
| decoder (IRD, or public use STB ) Automatically | | | | synchronously serial time code, divided into 24-way |
| extracted from the stream and processing of data, | | | | RS-232 signals, respectively, the total control input to |
| voice and image is complex. In the "Digital Video | | | | the broadcasting front compression system, network |
| Broadcasting standard Chinese business information" | | | | management server. Designed to read motherboard |
| GY/Z174-2001, time and date table TDT is | | | | serial CPU clock time calibration software, because |
| mandatory, there is a time offset table (TOT) was | | | | the clock is locked to the network multiplexer (MEM) |
| an optional provision. TDT receiver can be used | | | | of the server's clock, multiplexer TDT signals sent |
| directly as a display or real-time control, the middle | | | | time and standard time in agreement. In the |
| part can be replaced by another TDT code group. | | | | multiplexer, we will TDT publication cycle is set to 20 |
| Central Television and Cable Network Center, | | | | seconds, domestic programs are mostly on the star |
| Qingdao, standard time via synchronization and | | | | is set to 20 seconds, and a few provincial-level units |
| encoders into ASI stream, via satellite or cable | | | | is set to 30 seconds, 15 seconds. |
| set-top box to a satellite or cable set-top boxes, | | | | Fewer exports in the program for digital video |
| standard time after export or set-top box in the | | | | broadcasting environment, TDT time synchronization |
| image in panel show, also leads to terminals to more | | | | signal is not so complicated. Cable Network Center in |
| use, providing great convenience to the user. Time | | | | QCN Qingdao, ST3100H-GPS synchronized master |
| and date table (TDT) is so required, it is only UTC | | | | clock directly to the standard time with the RS-232 |
| time and date information transmission, contains only | | | | received the EPG server, the server will be through |
| one paragraph, grammatical structures in Table 1. | | | | the release of TDT is set to 5 seconds and repeat |
| Transmission of this table TS packet PID value of | | | | the cycle of hair seven times, so that set-top box |
| 0x0014, table_id to 0x70. | | | | just opened machine time, set-top box panel, and |
| Table 1 3, TDT signal of import and export | | | | browse the on-screen display will immediately update |
| structure and its test data | | | | the inaccurate time to standard time. (2) TDT signal |
| Up to 270Mbps in the digital video broadcasting | | | | derived |
| stream in the ASI, TDT signal to the ten thousandth | | | | In digital video broadcasting, the device's operating |
| far less space, it must be used to capture large | | | | system to TDT tables and other organic electronic |
| volumes of high-speed digital processing chips and | | | | program guide EPG to connect, to provide users with |
| related software, a separate signal generator and the | | | | a variety of applications, the TDT signal is derived |
| TDT TDT signal decoding equipment is rare, usually | | | | in-house applications, and related aspects are more |
| as the main signal (image and sound) and multiplexing | | | | more systematic, generally a small number of large |
| equipment codec functions exist. Through repeated | | | | system integrators. |