COMMUNICATION CONTROL METHOD, USER TERMINAL, AND PROCESSOR

• US 20160302152A1
• Filed: 11/25/2014
• Published: 10/13/2016
• Est. Priority Date: 11/26/2013
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: FUKUTA, Noriyoshi, MORITA, Kugo
• Granted Patent: US 10,251,126 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04H 20/38 Arrangements for distribution where lower stations, e.g. receivers, interact with the broadcast
• CPC Class Codes: H04J 11/00 Orthogonal multiplex systems, e.g. using WALSH codesH04J13/00 takes precedence
• CPC Class Codes: H04L 2012/5625 Operations, administration and maintenance [OAM]
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04W 4/023 using mutual or relative location information between multiple location based services [LBS] targets or of distance thresholds
• CPC Class Codes: H04W 40/246 Connectivity information discovery
• CPC Class Codes: H04W 52/0212 managed by the network, e.g. network or access point is master and terminal is slave
• CPC Class Codes: H04W 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 56/002 Mutual synchronization
• CPC Class Codes: H04W 60/02 by periodical registration
• CPC Class Codes: H04W 72/1215 for collaboration of different radio technologies
• CPC Class Codes: H04W 76/14 Direct-mode setup
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: H04W 88/16 Gateway arrangements
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A communication control method according to the present embodiment is used in a mobile communication system that supports a D2D proximity service. The communication control method comprises: an operation step of performing an operation for energy saving by a base station managing a cell in which a fixed-type user terminal, whose movement is restricted, exists; and a switching step of switching an operation mode from a normal mode to a power saving mode, by the user terminal, so that power consumption of an operation in the D2D proximity service is reduced, when the base station performs the operation for energy saving.

Claims

1. A communication control method used in a mobile communication system that supports a D2D proximity service, comprising:

an operation step of performing an operation for energy saving by a base station managing a cell in which a fixed-type user terminal, whose movement is restricted, exists; and

a switching step of switching an operation mode from a normal mode to a power saving mode, by the user terminal, so that power consumption of an operation in the D2D proximity service is reduced, when the base station performs the operation for energy saving.

2. The communication control method according to claim 1, wherein the operation in the D2D proximity service is at least one of a discovery operation for discovering a partner terminal in D2D communication or for being discovered by the partner terminal, and a transmission operation of a synchronization signal for establishing terminal-to-terminal synchronization.

3. The communication control method according to claim 1, wherein

in the operation step, as the operation for energy saving, the base station reduces transmission power of a radio signal, and

in the switching step, when received power of the radio signal becomes equal to or less than a threshold value, the user terminal switches the operation mode from the normal mode to the power saving mode.

4. The communication control method according to claim 3, comprising:

a step of setting, prior to the operation step, by the user terminal, the base station transmitting the radio signal whose received power becomes maximum in a predetermined time period as a designated base station, wherein

in the switching step, when the base station set as the designated base station performs the operation for energy saving, the user terminal switches the operation mode from the normal mode to the power saving mode, and

the communication control method further comprises a step of maintaining, by the user terminal, the base station as the designated base station even when the received power of the radio signal from the base station is no longer the maximum received power.

5. The communication control method according to claim 1, wherein

in the operation step, as the operation for energy saving, the base station reduces transmission power of a radio signal, and

in the switching step, when received power of the radio signal from a neighboring base station becomes equal to or more than a threshold value as a result of the operation for energy saving, the user terminal switches the operation mode from the normal mode to the power saving mode.

6. The communication control method according to claim 5, comprising:

a step of setting, prior to the operation step, by the user terminal, the neighboring base station transmitting the radio signal whose received power becomes maximum in a predetermined time period as a designated base station, wherein

in the switching step, when the received power of the radio signal from the neighboring base station set as the designated base station becomes equal to or more than a threshold value, the user terminal switches the operation mode from the normal mode to the power saving mode, and

the communication control method further comprises a step of maintaining, by the user terminal, the neighboring base station as the designated base station even when the received power of the radio signal from the neighboring base station is no longer the maximum received power.

7. The communication control method according to claim 1, wherein

in the operation step, as the operation for energy saving, the base station transmits, to the user terminal, terminal count information on the number of user terminals located in the cell, and

in the switching step, the user terminal switches the operation mode from the normal mode to the power saving mode on a basis of the terminal count information received from the base station.

8. The communication control method according to claim 7, wherein the terminal count information is information about at least any one of the total number of user terminals located in the cell, the number of user terminals per unit area, the number of user terminals per unit transmission power, the number of user terminals in a connected state, the number of user terminals in an idle state, the number of fixed-type user terminals, and the number of user terminals that desire to perform D2D communication.

9. The communication control method according to claim 7, further comprising the steps of:

broadcasting, by the base station, request information requesting information for obtaining the terminal count information; and

obtaining, by the base station, the terminal count information on a basis of a response to the request information.

10. The communication control method according to claim 9, wherein the information for obtaining the terminal count information is at least any one of information indicating a connected state of a user terminal, information indicating whether or not a user terminal is a fixed-type user terminal, and information on desire to perform the D2D communication.

11. The communication control method according to claim 7, further comprising the steps of:

registering, by the user terminal, location information of the user terminal in an upper network device than the base station, when the user terminal moves inside the cell;

acquiring, by the base station, from the network device, the location information registered in the network device; and

obtaining, by the base station, the terminal count information on a basis of the acquired location information.

12. The communication control method according to claim 1, wherein

in the operation step, as the operation for energy saving, the base station transmits, to the user terminal, a request for switching the operation mode from the normal mode to the power saving mode, and

in the switching step, the user terminal switches the operation mode from the normal mode to the power saving mode on a basis of the request received from the base station.

13. The communication control method according to claim 12, wherein

the operation in the D2D proximity service is at least one of a discovery operation for discovering a partner terminal in D2D communication or for being discovered by the partner terminal, and a transmission operation of a synchronization signal for establishing terminal-to-terminal synchronization, and

in the operation step, the base station transmits the request including restriction information of the discovery operation and/or of the transmission operation of the synchronization signal, the restriction information being applied when the operation mode is the power saving mode.

14. A user terminal configured to be a fixed-type user terminal whose movement is restricted and to be used in a mobile communication system that supports a D2D proximity service, comprising:

a controller configured to switch an operation mode from a normal mode to a power saving mode so that power consumption of an operation in the D2D proximity service is reduced, wherein

the controller switches the operation mode from the normal mode to the power saving mode when a base station managing a cell in which the user terminal exists performs an operation for energy saving.

15. The user terminal according to claim 14, wherein the operation in the D2D proximity service is at least one of a discovery operation for discovering a partner terminal in D2D communication or for being discovered by the partner terminal, and a transmission operation of a synchronization signal for establishing terminal-to-terminal synchronization.

16. The user terminal according to claim 15, wherein when received power of a radio signal from the base station becomes equal to or less than a threshold value, the controller switches the operation mode from the normal mode to the power saving mode.

17. The user terminal according to claim 16, wherein

the controller sets the base station transmitting the radio signal whose received power becomes maximum in a predetermined time period as a designated base station,

the controller switches the operation mode from the normal mode to the power saving mode, when the base station set as the designated base station performs the operation for energy saving, and

the controller maintains the base station as the designated base station even when the received power of the radio signal from the base station is no longer the maximum received power.

18. The user terminal according to claim 15, wherein when received power of a radio signal from an neighboring base station becomes equal to or more than a threshold value as a result of the operation for energy saving, the controller switches the operation mode from the normal mode to the power saving mode.

19. The user terminal according to claim 18, wherein

the controller sets the neighboring base station transmitting the radio signal whose received power becomes maximum in a predetermined time period as a designated base station,

the controller switches the operation mode from the normal mode to the power saving mode, when the received power of the radio signal from the neighboring base station set as the designated base station becomes equal to or more than a threshold value, and

the controller maintains the neighboring base station as the designated base station even when the received power of the radio signal from the neighboring base station is no longer the maximum received power.

20. The user terminal according to claim 15, further comprising:

a receiver configured to receive, from the base station, terminal count information on the number of user terminals located in the cell, wherein

the controller switches the operation mode from the normal mode to the power saving mode on a basis of the terminal count information received from the base station.

21. The user terminal according to claim 15, further comprising:

a receiver configured to receive, from the base station, a request for switching, by the user terminal, the operation mode from the normal mode to the power saving mode, wherein the controller switches the operation mode from the normal mode to the power saving mode on a basis of the request received from the base station.

22. (canceled)