Base station optical fiber time service system based on BD/GPS double antennas

Abstract

The invention discloses a base station optical fiber time service system based on BD / GPS double antennas, which comprises at least one satellite antenna, a BBU synchronization system host and a plurality of BBU synchronization system slaves. The satellite antenna is connected with the host, and the host is connected with all the slaves through optical fibers; wherein the host comprises a satellite signal receiving module with a 1PPS + TOD receiving unit, and the satellite signal receiving module can analyze satellite signals to obtain 1PPS + TOD time information. According to the time service system disclosed by the invention, satellite signals can be cascaded with a plurality of BBU equipment only by a set of BD / GPS antenna without a cable feeder, so that the number of antennas can be greatly reduced, the occupation of sky surface resources and machine room space is reduced, high-precision time synchronization information is provided for a mobile base station, and the time accuracy of all BBUs can be highly consistent; deployment and maintenance are simple, upgrading and capacity expansion are convenient, automatic opening and automatic maintenance can be achieved, the fault rate is reduced, and the base station construction cost is reduced.

Description

technical field [0001] The invention belongs to the technical field of communication systems, relates to the fields of time-frequency synchronization and base station construction, and in particular to a base station optical fiber timing system based on BD / GPS dual antennas. Background technique [0002] The communication network transitions from an analog communication network to a digital optical fiber communication network. Since the information transmission in the digital optical fiber communication network is realized by frequency division multiplexing (FDM) and time division multiplexing (TDM) technology, frequency synchronization and time synchronization are guaranteed The communication network is the key to realizing communication and communication quality. Once the synchronization is abnormal, the bit error rate will increase, the communication quality will decrease, and the communication will be interrupted or even the network will be paralyzed. The wireless base s...

AI Technical Summary

Problems solved by technology

[0008] Although the above two solutions have solved the problem of multiple BBUs (that is, BBU pools) sharing a set of BD / GPS antennas to a certain extent, there are still several major defects: First, they do not solve the problem of ensuring high-precision synchronization of BBUs. The distance between the satellite antenna and the BBU pool group is far away. The above-mentioned distance is at the expense of the BBU time synchronization accuracy index; the second is that the delay problem from the antenna to the BBU pool group is not solved; the third is that the 5G base station cannot meet the 260ns , 130ns high-precision time synchronization requirements, not to mention meeting the 5G 10ns high-precision positioning requirements; Fourth, manual deployment is required, the deployment time is long, the construction cost of the deployment is high, and the maintenance cost is also high

[0009] The "5G Synchronous Networking Architecture and Key Technologies White Paper" released by the IMT-2020 (5G) Promotion Group in 2020 clearly pointed out that although the time synchronization requirements of 5G Time Division Duplex (TDD) and 4G Time Division Duplex (TDD) are the same, both It is 3 microseconds, but 5G collaborative enhancement puts forward more stringent requirements for time synchronization accuracy

[0010] Due to the transmission delay caused by radio frequency cables and optical fibers, the time synchronization accuracy of the BBU can only reach 3 microseconds, which cannot meet the needs of 5G base stations for high-precision time synchronization. Therefore, the above two solutions have serious defects.

Images