Method and apparatus of implementing time synchronization

• US 10,375,662 B2
• Filed: 06/12/2017
• Issued: 08/06/2019
• Est. Priority Date: 01/26/2011
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Feng, Liexun, He, Yong
• Primary Examiner(s): Smith, Marcus
• Assistant Examiner(s): Jones, Prenell P
• Application Number:
  US15/619,806
• Publication Number:
  US 20170280405A1
• Time in Patent Office: 785 Days
• CPC Class Codes: H04B 10/25 Arrangements specific to fibre transmission
• CPC Class Codes: H04B 10/25753 Distribution optical network, e.g. between a base station and a plurality of remote units
• CPC Class Codes: H04J 14/0204 Broadcast and select arrangements, e.g. with an optical splitter at the input before adding or dropping
• CPC Class Codes: H04J 3/0638 Clock or time synchronisation among nodes; Internode synchronisation synchronization for ring networks H04L12/422; data switching networks with synchronous transmission H04L12/43
• CPC Class Codes: H04J 3/0667 Bidirectional timestamps, e.g. NTP or PTP for compensation of clock drift and for compensation of propagation delays arrangements for monitoring round trip delays in packet switching networks H04L43/0864
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others
• CPC Class Codes: H04W 88/085 Access point devices with remote components

Abstract

A method of time synchronization and a base station system are disclosed. The base station system includes a main unit, at least one radio unit, and a transmission medium adapted to transmit information between the main unit and the at least one radio unit. The base station system further includes a clock synchronization server configured close to the side of the at least one radio unit or integrated with the at least one radio unit. The clock synchronization server is adapted to transmit synchronization data to the main unit through the transmission medium, so that the main unit performs configuration processing according to the synchronization data to implement time synchronization with the clock synchronization server.

Claims

1. A base station, comprising:

a plurality of remote radio units (RRUs) to transmit service data;

a clock synchronization server to transmit first synchronization data;

a first optical adapter including a first optical fiber interface and in communication with the plurality of RRUs and the clock synchronization server, the first optical adapter configured to converge the synchronization data from the clock synchronization server and service data from the plurality of RRUs;

a main system configured to receive the first synchronization data from a clock synchronization server and perform configuration processing according to the first synchronization data to implement time synchronization with the clock synchronization server, the main system including;

a second optical adapter configured to split the converged synchronization data and the service data,

a plurality of baseband control units (BBUs), and

one or more transfer switches

configured to cause transmitting synchronization data from the clock synchronization server to the plurality of BBUs.

2. The base station according to claim 1,

wherein the at least one optical fiber is configured to be connected to cause transmitting information between the main system and the plurality of RRUs and synchronization data from the clock synchronization server to the main system.

3. The base station according to claim 2, wherein the plurality of BBUs are installed in a machine room in a centralized manner.

4. The base station according to claim 3, wherein the plurality of RRU are installed outdoors close to at least one antenna.

5. The base station according to claim 1, wherein

each of the plurality of BBUs comprises a baseband radio frequency interface and a synchronization interface coupled to the second optical adapter,

the baseband radio frequency interface is configured to transmit and receive service data, and

the synchronization interface is configured to transmit synchronization data.

6. The base station according to claim 5, wherein the first optical adapter and the second optical adapter are optical add-drop multiplexers (OADMs).