Synchronization method and base station

• US 9,736,799 B2
• Filed: 02/16/2015
• Issued: 08/15/2017
• Est. Priority Date: 08/24/2012
• 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: Wu, Qian, Xue, Lixia, Ma, Sha
• Primary Examiner(s): Duong, Christine
• Application Number:
  US14/623,389
• Publication Number:
  US 20150163760A1
• Time in Patent Office: 911 Days
• Field of Search: None
• CPC Class Codes: H04W 56/0005 synchronizing of arrival of multiple uplinks
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others
• CPC Class Codes: H04W 92/20 between access points

Abstract

Embodiments of the present application provide a synchronization method and a base station. In the embodiments of the present application, a first base station receives, on at least one part of channels in a receiving band supported by the first base station, at least one first downlink synchronization signal sent by at least one second base station, and selects a first downlink synchronization signal from the at least one first downlink synchronization signal, to enable the first base station to execute time synchronization according to the selected first downlink synchronization signal, which can avoid a problem in the prior art of low reliability of time synchronization caused by low availability of a GPS signal, and relieve interference suffered by a base station from another base station caused by a problem of asynchronous receiving and sending time or inaccurate time synchronization, thereby improving signal quality of an air interface.

Claims

1. A synchronization method, comprising:

receiving, by a first base station, on at least one part of channels in a receiving band supported by the first base station, at least one first downlink synchronization signal sent by at least one second base station;

selecting, by the first base station, a first downlink synchronization signal from the at least one first downlink synchronization signal;

executing, by the first base station, time synchronization according to the selected first downlink synchronization signal;

wherein selecting, by the first base station, a first downlink synchronization signal from the at least one first downlink synchronization signal comprises;

receiving, by the first base station, on the at least one part of channels, a first reference signal sent by the at least one second base station;

measuring, by the first base station, the first reference signal, to obtain a signal intensity of the first reference signal;

subtracting, by the first base station, an offset of each of the second base station relative to the first base station from the signal intensity of the first reference signal sent by each of the second base station, to obtain strength of interference caused by each of the second base station on a channel where the first base station currently works through sending signal on the at least one part of channels for the first base station; and

selecting, by the first base station, the first downlink synchronization signal according to the strength of interference caused by each of the second base station on the channel where the first base station currently works through sending signal on the at least one part of channels of the first base station.

2. The method according to claim 1, wherein selecting the first downlink synchronization signal further comprises:

selecting, by the first base station, a first downlink synchronization signal sent by a second base station of strongest strength of interference.

3. The method according to claim 1, wherein before executing, by the first base station, time synchronization according to the selected first downlink synchronization signal, the method further comprises:

receiving, by the first base station, on the at least one part of channels, subframe configuration information sent by the each of the second base station, wherein the subframe configuration information is used to indicate a working mode of a subframe of each of the second base station.

4. The method according to claim 3, wherein after executing, by the first base station, time synchronization according to the selected first downlink synchronization signal, the method further comprises:

configuring, by the first base station, a working mode of a subframe of the first base station according to the subframe configuration information sent by a second base station corresponding to the selected first downlink synchronization signal.

5. The method according claim 1, wherein after executing, by the first base station, time synchronization according to the selected first downlink synchronization signal, the method further comprises:

receiving, by the first base station, according to working frequency information of the at least one second base station, on a channel indicated by the frequency information, a second downlink synchronization signal sent by the at least one second base station;

selecting, by the first base station, a second downlink synchronization signal from the second downlink synchronization signal; and

executing, by the first base station, the time synchronization according to the selected second downlink synchronization signal.

6. The method according to claim 5, wherein selecting the second downlink synchronization signal from the second downlink synchronization signal comprises:

receiving, by the first base station, according to the working frequency information of the at least one second base station, on the channel indicated by the frequency information, a second reference signal sent by the at least one second base station;

measuring, by the first base station, the second reference signal, to obtain signal intensity of the second reference signal; and

selecting, by the first base station, a first downlink synchronization signal sent by a second base station corresponding to a second reference signal of strongest signal intensity in the second reference signal.

7. The method according to claim 6, wherein selecting the second downlink synchronization signal from the second downlink synchronization signal further comprises:

receiving, by the first base station, according to the working frequency information of the at least one second base station, on the channel indicated by the frequency information, a second reference signal sent by the at least one second base station;

measuring, by the first base station, the second reference signal, to obtain signal intensity of the second reference signal;

subtracting, by the first base station, a preset offset of each of the second base station relative to the first base station from the signal intensity of the second reference signal, to obtain strength of interference caused by the second base station on the channel where the first base station currently works through sending signal on the channel indicated by the frequency information for the first base station; and

selecting, by the first base station, a second downlink synchronization signal sent by a second base station of strongest strength of interference.

8. The method according to claim 5, wherein before receiving the second downlink synchronization signal sent by the at least one second base station, the method further comprises:

receiving, by the first base station, on the at least one part of channels, an operator identifier of an operator to which the at least one second base station belongs sent by the at least one second base station.

9. The method according to claim 5, wherein receiving the second downlink synchronization signal sent by the at least one second base station comprises:

receiving, by the first base station, according to the working frequency information of the at least one second base station and the operator identifier, on the channel indicated by the frequency information, a second downlink synchronization signal sent by a part of second base stations in the at least one second base station, wherein the part of the second base stations belong to different operators.

10. A base station, comprising:

a processor; and

a receiver coupled to the processor, the receiver configured to;

receive, on at least one part of channels in a receiving band supported by the base station, at least one first downlink synchronization signal sent by at least one second base station, and transmit the first downlink synchronization signal to a processor; and

receive, on the at least one part of channels, a first reference signal sent by the at least one second base station, and transmit the first reference signal to the processor;

the processor configured to;

select a first downlink synchronization signal from the at least one first downlink synchronization signal, and execute time synchronization according to the selected first downlink synchronization signal;

measure the first reference signal, to obtain signal intensity of the first reference signal; and

subtract a preset offset of each of the at least one second base station relative to the base station from the signal intensity of the first reference signal, to obtain strength of interference caused by each of the second base station on a channel where the base station currently works through sending signal on the at least one part of channels for the base station, and select a first downlink synchronization signal sent by a second base station of strongest strength of interference.

11. The base station according to claim 10, wherein the receiver is further configured to:

receive, on the at least one part of channels, subframe configuration information sent by the each of the second base station, wherein the subframe configuration information is used to indicate a working mode of a subframe of each of the second base station.

12. The base station according to claim 11, wherein:

the receiver is further configured to transmit the subframe configuration information to the processor; and

the processor is further configured to configure a working mode of a subframe of the base station according to the subframe configuration information sent by a second base station corresponding to the selected first downlink synchronization signal.

13. The base station according to claim 10, wherein:

the receiver is further configured to;

receive, according to working frequency information of the at least one second base station, on a channel indicated by the frequency information, a second downlink synchronization signal sent by the at least one second base station, and transmit the second downlink synchronization signal to the processor; and

the processor is further configured to;

select a second downlink synchronization signal from the second downlink synchronization signal, and execute the time synchronization according to the selected second downlink synchronization signal.

14. The base station according to claim 13, wherein:

the receiver is further configured to;

receive, according to the working frequency information of the at least one second base station, on the channel indicated by the frequency information, a second reference signal sent by the at least one second base station, and transmit the second reference signal to the processor; and

the processor is configured to;

measure the second reference signal, to obtain signal intensity of the second reference signal, and

select a first downlink synchronization signal sent by a second base station corresponding to a second reference signal of strongest signal intensity in the second reference signal;

or subtract a preset offset of each of the second base station relative to the base station from the signal intensity of the second reference signal, to obtain strength of interference caused by the second base station on the channel where the base station currently works through sending signal on the channel indicated by the frequency information for the base station, and select a second downlink synchronization signal sent by a second base station of strongest strength of interference.

15. The base station according to claim 13, wherein the receiver is further configured to:

receive, on the at least one part of channels, an operator identifier of an operator to which the at least one second base station belongs sent by the at least one second base station.

16. The base station according to claim 13, wherein the receiver is configured to:

receive, according to the working frequency information of the at least one second base station and the operator identifier, on the channel indicated by the frequency information, a second downlink synchronization signal sent by a part of second base stations in the at least one second base station, wherein the part of the second base stations belong to different operators.

17. A synchronization method, the method comprising:

receiving, by a first base station, on at least one part of channels in a receiving band supported by the first base station, at least one first downlink synchronization signal sent by at least one second base station;

selecting, by the first base station, a first downlink synchronization signal from the at least one first downlink synchronization signal;

executing, by the first base station, time synchronization according to the selected first downlink synchronization signal;

receiving, by the first base station, according to working frequency information of the at least one second base station, on a channel indicated by the frequency information, a second downlink synchronization signal sent by the at least one second base station;

selecting, by the first base station, a second downlink synchronization signal from the second downlink synchronization signal;

executing, by the first base station, the time synchronization according to the selected second downlink synchronization signal;

wherein selecting, by the first base station, the second downlink synchronization signal from the second downlink synchronization signal comprises;

receiving, by the first base station, according to the working frequency information of the at least one second base station, on the channel indicated by the frequency information, a second reference signal sent by the at least one second base station;

measuring, by the first base station, the second reference signal, to obtain signal intensity of the second reference signal;

selecting, by the first base station, a first downlink synchronization signal sent by a second base station corresponding to a second reference signal of strongest signal intensity in the second reference signal;

receiving, by the first base station, according to the working frequency information of the at least one second base station, on the channel indicated by the frequency information, a second reference signal sent by the at least one second base station;

measuring, by the first base station, the second reference signal, to obtain signal intensity of the second reference signal;

subtracting, by the first base station, a preset offset of each of the second base station relative to the first base station from the signal intensity of the second reference signal, to obtain strength of interference caused by the second base station on the channel where the first base station currently works through sending signal on the channel indicated by the frequency information for the first base station; and

selecting, by the first base station, a second downlink synchronization signal sent by a second base station of strongest strength of interference.