METHOD FOR ENHANCING SMALL CELL

• US 20150365831A1
• Filed: 01/09/2014
• Published: 12/17/2015
• Est. Priority Date: 01/10/2013
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: KO, Young Jo, AHN, Jae Young, SEO, Bang Won
• Granted Patent: US 9,712,308 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/1469 using time-sharing
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

Disclosed is a method for enhancing a small cell. A method for enhancing a small cell in a terminal applying inter-site CA includes the steps of: causing a terminal to transmit the uplink control information (UCI) of at least one of the macro cells controlled by a macro cell base station through the macro cell; and causing the terminal to transmit the uplink control information of at least one of the small cells controlled by a small cell base station through the small cell.

Claims

1. A method for enhancing a small cell, which is performed by a terminal applying inter-site carrier aggregation (CA), the method comprising:

transmitting uplink control information regarding at least one of macro cells managed by a macro cell base station through the macro cell; and

transmitting uplink control information regarding at least one of small cells managed by a small cell base station through the small cell.

2. A method for enhancing a small cell, which is performed by a base station supporting inter-site CA, the method comprising:

setting a plurality of cells as cell groups;

setting the cell groups as a primary cell group and at least one secondary cell group; and

transmitting information on the set cell groups to the terminal.

3. The method of claim 2, wherein the setting of a plurality of cells as cell groups comprises setting cells managed by one base station as one cell group.

4. The method of claim 2, wherein the setting of a plurality of cells as cell groups comprises grouping the plurality of cells as a cell group composed of macro cells and a cell group composed of the small cells.

5. The method of claim 2, wherein the setting of the cell groups as a primary cell group and at least one secondary cell group further comprises:

setting one primary cell for each cell group; and

setting cells other than the primary cell as secondary cells.

6. The method of claim 5, wherein the primary cell of the primary cell group provides coverage of the terminal and manages mobility of the terminal, and the secondary cell group transmits and receives data to and from the terminal.

7. The method of claim 5, wherein a downlink control channel transmitted to schedule a downlink data channel or uplink data channel for cells belonging to the cell group is transmitted to the terminal through the cells belonging to the cell group.

8. The method of claim 5, wherein the primary cell of the each cell group is always maintained in an activation state, and cells other than the primary cell are activated by an activation command of the base station and deactivated by a deactivation command of the base station.

9. The method of claim 5, wherein the terminal monitors a downlink control channel transmitted through the primary cell of the primary cell group, and the base station delivers system information regarding cells other than the primary cell to the terminal.

10. A method for enhancing a small cell, which is performed by a terminal applying inter-site CA having non-ideal backhaul, the method comprising:

receiving indication information regarding a transmission form of an uplink control channel from a base station; and

transmitting only one of a first uplink control channel for a first cell group and a second uplink control channel for a second cell group to a corresponding cell group or simultaneously transmitting the first uplink control channel and the second uplink control channel to respective cell groups based on the received indication information.

11. The method of claim 10, wherein the transmitting of the uplink control channel comprises transmitting the first uplink control channel through a primary cell or a predetermined cell of the first cell group or transmitting the second uplink control channel through a primary cell or a predetermined cell of the second cell group while not simultaneously transmitting the first uplink control channel and the second uplink control channel in the same subframe.

12. The method of claim 10, wherein the transmitting of the uplink control channel comprises transmitting the first uplink control channel through a primary cell or a predetermined cell of the first cell group or transmitting the second uplink control channel through a primary cell or a predetermined cell of the second cell group while simultaneously transmitting the first uplink control channel and the second uplink control channel in the same subframe.

13. The method of claim 10, further comprising:

transmitting power headroom information of an uplink for a serving cell used for uplink control channel transmission of the first cell group when the base station transmits uplink control information regarding the first cell group, transmitting power headroom information of an uplink for a serving cell used for uplink control channel transmission of the second cell group when the base station transmits uplink control information regarding the second cell group, transmitting power headroom information of an uplink for a serving cell used for uplink control channel transmission of the first cell group when the base station simultaneously transmits uplink control information to both of the first cell group and the second cell group, or transmitting power headroom information of an uplink for a serving cell used for uplink control channel transmission of the second cell group when the base station simultaneously transmits the uplink control information to both of the first cell group and the second cell group.

14. A method for enhancing a small cell, which is performed by a terminal having dual connectivity with two reception points, the method comprising:

receiving uplink transmission timing information corresponding to the two reception points from a base station; and

performing uplink transmission in any subframe using a specific reception point corresponding to the subframe and an uplink transmission timing corresponding to the specific reception point.

15. The method of claim 14, wherein the performing of the uplink transmission comprises, when two uplink subframes, which are temporally neighbored, correspond to different reception points and transmission timings of the two uplink subframes overlap each other, selecting, by the terminal, any one of the two subframes according to a predetermined priority and performing uplink transmission only through the selected subframe.

16. The method of claim 14, wherein the uplink transmission timings of the two reception points are set to be the same based on one of the two reception points.

17. A method for enhancing a small cell, which is performed by a terminal applying inter-eNB CA in a frequency division duplex (FDD) type base station and a time division duplex (TDD) type base station, the method comprising transmitting HARQ-ACK information for a downlink channel transmitted by an FDD type cell and HARQ-ACK information for a downlink channel transmitted by a TDD type cell via an uplink of the FDD type cell.

18. A method for enhancing a small cell, which is performed by a terminal, the method comprising:

receiving TDD carrier configuration information including an additional carrier configuration; and

transmitting a sounding reference signal in some or all of special subframes of a TDD carrier based on the received TDD carrier configuration information.

19. The method of claim 18, wherein the additional carrier configuration is composed of only downlink subframes and special subframes.

20. The method of claim 18, further comprising transmitting, by the terminal, uplink data using an uplink subframe of an FDD carrier or using a TDD carrier having the uplink subframe.