The time synchronization server is very important to TV stations. It is the benchmark for all broadcasting and switching between TV program automation, studio, external signals (including satellite signals, broadcasting vehicle signals, microwave signals, etc.). Especially for the digital television broadcasting system, the normal broadcast and on-time switching of the program must be based on a highly uniform time source of time synchronization server.

From the complete broadcasting system, TV stations often require a precise external time signal, which is mainly connected to UTC. The reference clock signal is used as the initial signal for time synchronization of the whole system. It also requires the access of the time synchronization signal in the broadcasting system to ensure the consistency of all devices and links, and provide strong support for the smooth and complete switching of the signal source outside the broadcasting system and the signal picture inside the system.

The function requirement of common TV network time synchronization server is to provide a unified time base for the entire digital TV system. The whole system is based on the GPS satellite time as the standard time source, and the direct subsystem includes: loader system, satellite security system, monitoring and monitoring system, satellite reception system and so on. The subsystems connected to the clock through data network are: 3 CA systems, EPG systems, OCG systems, CMS systems, one way front end hardware systems.

The most popular calibration signals at this stage are from the GPS Beidou network time synchronization server, taking UTC time as the reference standard, and at the same time establishing two main clock systems. When the main circuit clock equipment fails, it can cut the signals of the backup system in time, and provide accurate time synchronization reference numbers for all the systems in the whole station.

As shown in the above diagram, the main equipment clock system recommended is the SYN2151 type time synchronization server. The technical performance is fully in line with the technical requirements of a radio station. The specific requirements are as follows:

1, support single GPS, single Beidou, GPS Beidou combination time service mode;

2, built-in phase locked constant temperature crystal or rubidium atomic clock for punctuality, punctual accuracy < 1ms (72 hours);

3, the timing accuracy is 1-10ms.

4, enterprise 7*24 hours work, providing 3 years warranty and standby service;

5. MTBF should be at least 80000 hours.

6, NTP request volume is greater than 14000 times / sec (single port), and support client access to more than 10000.

7, support at least 4 independent 10/100/1000 Base-T Ethernet ports, support gigabit network, physical isolation between ports, support IPv4 and IPv6;

8, support for the leap seconds require active processing mechanism, but not limited to strictly in accordance with international standards in time to synchronize the UTC time or support step adjustment function, can automatically handle leap seconds, the client can gradually complete the correction before the leap seconds.

9, there is heartbeat detection function, single machine support double network binding, dual 1+1 network interface binding, support virtual IP; support dual hot standby mode, host to each other detection state, support virtual IP, single machine failure automatic switching;

10, the antenna requires lightning protection measures;

11, the working voltage is AC:220V + 10% 47-63Hz;

12. The working environment temperature is 0 - 45 C, and the storage environment temperature is -20 - 70 C;

13. Issue the third party inspection report.

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