Multi-cell communication method and system of a mobile terminal, a micro base station, and a macro base station

• US 9,474,005 B2
• Filed: 11/05/2013
• Issued: 10/18/2016
• Est. Priority Date: 05/10/2010
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kwon, Tae Soo, Jang, Kyung Hun, Lim, Jong Bu, Shin, Chang Yong
• Primary Examiner(s): Karikari, Kwasi
• Application Number:
  US14/072,236
• Publication Number:
  US 20140073332A1
• Time in Patent Office: 1,078 Days
• Field of Search: 455/436, 370/331
• US Class Current: 1/1
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/322 by location data
• CPC Class Codes: H04W 64/003 locating network equipment
• CPC Class Codes: H04W 72/00 Local resource management
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: H04W 92/20 between access points

Abstract

Communication methods of a macro base station which collects position information about a mobile micro base station and that is served by the macro base station, predicts a channel between the macro base station and the micro base station, and performs a handover between the macro base station and the micro base station based on a state of the predicted channel is provided.

Claims

1. A communication method of a macro base station, the communication method comprising:

receiving a handover request message of a terminal, through a control channel between the terminal and the macro base station;

in response to the handover request message,

in response to a target base station of a handover being the macro base station, establishing a data channel between the terminal and the macro base station, and

in response to the target base station of the handover being a micro base station, transmitting data to the micro base station in a cell coverage of the macro base station; and

continuously maintaining the control channel between the terminal and the macro base station after the handover is completed, regardless of whether the target base station of the handover is the micro base station or the macro base station, regardless of the terminal requesting a handover to be performed from the micro base station to another micro base station, and regardless of whether or not the terminal requests the handover to be performed from the micro base station to the other micro base station.

2. The communication method of claim 1, further comprising:

determining whether the target base station of the handover is the micro base station or the macro base station, based on the handover request message.

3. The communication method of claim 1, wherein the transmitting of the data to the micro base station comprises:

disconnecting the data channel between the macro base station and the terminal, in response to a handover of the terminal being performed from the macro base station to the micro base station.

4. The communication method of claim 1, further comprising:

disconnecting the control channel between the macro base station and the terminal, in response to the terminal establishing a control channel with another macro base station.

5. The communication method of claim 1,

wherein the micro base station and the macro base station comprise a channel prediction database, and

wherein the channel prediction database stores information about channels between the micro base station and the macro base station, based on possible positions of the micro base station.

6. The communication method of claim 5, further comprising:

predicting a channel between the micro base station and the macro base station, by using the channel prediction database.

12. A non-transitory computer-readable recording medium storing a program to implement the method of claim 1.

7. A communication method of a terminal, the communication method comprising:

transmitting a handover request message of the terminal to a macro base station, through a control channel between the terminal and the macro base station;

determining whether a target base station of a handover is the macro base station or a micro base station, and

in response to the target base station of the handover being the macro base station, establishing a data channel between the terminal and the macro base station, and

in response to the target base station of the handover being a micro base station, receiving data from the micro base station; and

regardless of whether the target base station of the handover is the micro base station or the macro base station, continuously maintaining the control channel between the terminal and the macro base station after the handover is completed, until a control channel between the terminal and another macro base station is established.

8. The communication method of claim 7, wherein the receiving of the data from the micro base station comprises:

establishing a data channel between the micro base station and the terminal, while the control channel between the terminal and the macro base station is continuously maintained.

9. The communication method of claim 7, further comprising:

comparing a quality of a signal received from the micro base station with a predetermined value; and

requesting the macro base station for a handover to the micro base station or another micro base station, through the control channel being continuously maintained, based on a result of the comparison.

10. The communication method of claim 9, further comprising:

establishing a new control channel and a new data channel between the other micro base station and the terminal while the control channel between the terminal and the macro base station is continuously maintained.

11. A communication method of a terminal, the communication method comprising:

transmitting a handover request message of the terminal to a macro base station, through a control channel between the terminal and a macro base station, wherein the transmitting of the handover request message of the terminal comprises

determining whether a level of a broadcast signal received from a micro base station is a predetermined value or more, and

based on a determination that the level of a broadcast signal received from a micro base station is the predetermined value or more, transmitting the handover request message requesting a handover from the macro base station to the micro base station, through the control channel between the terminal and the macro base station;

determining whether a target base station of the handover is the macro base station or the micro base station, and

in response to the target base station of the handover being the macro base station, establishing a data channel between the terminal and the macro base station, and

in response to the target base station of the handover being a micro base station, receiving data from the micro base station; and

continuously maintaining the control channel between the terminal and the macro base station after the handover is completed, regardless of whether the target base station of the handover is the micro base station or the macro base station.

13. A macro base station, comprising:

a message reception unit configured to receive a handover request message of a terminal, through a control channel between the terminal and the macro base station;

a data channel establishment unit configured to, in response to the handover request message,

when a target base station of a handover is the macro base station, establish a data channel between the terminal and the macro base station, and

when the target base station of the handover is the micro base station, transmit data to a micro base station in a cell coverage of the macro base station; and

a channel maintenance unit configured to continuously maintain the control channel between the terminal and the macro base station after the handover is completed, regardless of whether the target base station of the handover is the micro base station or the macro base station,

wherein the channel maintenance unit is further configured to continuously maintain the control channel between the terminal and the macro base station regardless of the terminal requesting a handover to be performed from the micro base station to another micro base station and when the terminal requests the handover to be performed from the micro base station to the other micro base station.

14. The macro base station of claim 13, wherein the macro base station is configured to determine whether the target base station of the handover is the micro base station or the macro base station based on the handover request message, and

the data channel establishment unit is configured to establish a data channel between the macro base station and the terminal or between the micro base station and the terminal based on a result of the determination.

15. The macro base station of claim 13, wherein the channel maintenance unit is configured to disconnect the control channel between the macro base station and the terminal in response to the terminal establishing a control channel with another macro base station.

16. A terminal, comprising:

a message transmission unit configured to transmit a handover request message of the terminal to a macro base station, through a control channel between the terminal and the macro base station;

a data channel establishment unit configured

to establish a data channel between the terminal and the macro base station when a target base station of a handover is the macro base station, and

to receive data from the micro base station when the target base station of the handover is the micro base station; and

a control channel maintenance unit configured to continuously maintain the control channel between the terminal and the macro base station after the handover is completed, regardless of whether the target base station of the handover is the micro base station or the macro base station,

wherein the control channel maintenance unit is further configured to continuously maintain the control channel between the terminal and the macro base station until a control channel between the terminal and another macro base station is established.

17. The terminal of claim 16, wherein in response to a signal reporting that a handover from the macro base station to another micro base station is completed in response to the handover request message of the terminal being received,

the control channel maintenance unit is configured to establish a new control channel between the other micro base station and the terminal while the control channel between the terminal and the macro base station is continuously maintained, and

the data channel establishment unit is configured to disconnect the data channel between the terminal and the macro base station, and establish a new data channel between the other micro base station and the terminal.