METHOD AND APPARATUS FOR TRANSMITTING UPLINK SIGNAL OR UPLINK CHANNEL

• US 20150223213A1
• Filed: 02/06/2015
• Published: 08/06/2015
• Est. Priority Date: 02/06/2014
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: MOON, Sung-Hyun, KO, Young Jo, KIM, Cheulsoon, SHIN, Joonwoo
• Granted Patent: US 9,414,335 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 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels
• CPC Class Codes: H04W 52/34 TPC management, i.e. sharing limited amount of power among users or channels or data types, e.g. cell loading
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff
• CPC Class Codes: H04W 52/54 Signalisation aspects of the TPC commands, e.g. frame structure
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

A method for transmitting a sounding reference signal (SRS) by a terminal in an environment in which a first carrier corresponding to a first serving cell and a second carrier corresponding to a second serving cell are aggregated is provided. The terminal receives first downlink control information (DCI) which is used for downlink scheduling and includes a first transmit power control (TPC) command through the first serving cell. The terminal controls transmit power of the SRS based on the first TPC command for transmit power control of the SRS. Next, the terminal transmits the SRS through the second serving cell using the controlled transmit power.

Claims

1. A method for transmitting a sounding reference signal (SRS) by a terminal in an environment in which a first carrier corresponding to a first serving cell and a second carrier corresponding to a second serving cell are aggregated, the method comprising:

receiving first downlink control information (DCI) which is used for downlink scheduling and includes a first transmit power control (TPC) command through the first serving cell;

controlling transmit power of the SRS based on the first TPC command for transmit power control of the SRS; and

transmitting the SRS through the second serving cell using the controlled transmit power.

2. The method of claim 1, wherein the second serving cell comprises a secondary cell using time division duplexing (TDD) for the terminal,

one radio frame for the second serving cell comprises only a plurality of downlink sub-frames and at least one special sub-frame, and

the special sub-frame comprises a downlink pilot time slot, a guard period, and an uplink pilot time slot, and has one of a 5 ms periodicity and a 10 ms periodicity.

3. The method of claim 2, wherein the first DCI comprises all fields that one of a DCI format 1, a DCI format 1A, a DCI format 1 B, a DCI format 1 D, a DCI format 2, a DCI format 2A, a DCI format 2B, a DCI format 2C, and a DCI format 2D defined for a Long Term Evolution (LTE) system or a LTE Advanced (LTE-A) system has, and further comprises a field for the first TPC command having two bits.

4. The method of claim 3, wherein the controlling of the transmit power of the SRS comprises controlling transmit power of the SRS based on the first TPC command of the first DCI received from at least a fourth downlink sub-frame before a first special sub-frame in which the SRS is transmitted among the special sub-frames.

5. The method of claim 3, wherein the receiving of the first DCI comprises receiving the first DCI within a first sub-frame group defined for receiving the first DCI, and

the controlling of the transmit power of the SRS comprises controlling transmit power of the SRS based on the first TPC command of the first DCI which is finally received among the first DCIs received within the first sub-frame group.

6. The method of claim 3, wherein the receiving of the first DCI comprises receiving the first DCI within a first sub-frame group defined for receiving the first DCI, and

the controlling of the transmit power of the SRS comprises:

accumulating power control value corresponding to the first TPC command of the first DCI received within the first sub-frame group, respectively; and

controlling transmit power of the SRS based on the accumulated power control value.

7. The method of claim 1, further comprising receiving a second DCI for an uplink TPC through a first serving cell serving as a primary cell for the terminal,

wherein the second DCI comprises a plurality of second TPC commands for a physical uplink shared channel (PUSCH) that one of a DCI format 3 and a DCI format 3A defined for a LTE (Long Term Evolution) system or a LTE-A (LTE-Advanced) system has, and further comprises a carrier indicator (CI) indicating a cell to which the second TPC command is applied.

8. The method of claim 7, further comprising:

determining a third TPC command for the terminal among the plurality of second TPC commands included in the second DCI; and

controlling transmit power of the SRS to be transmitted through the second serving cell based on the third TPC command when the CI included in the second DCI indicates the second serving cell which is a secondary cell for the terminal.

9. The method of claim 8, wherein the third TPC command is one of 2 bits and 1 bit, and

the CI is 3 bits and is located before the plurality of second TPC commands.

10. A method for transmitting a sounding reference signal (SRS) by a terminal in an environment in which a first carrier corresponding to a first serving cell and a second carrier corresponding to a second serving cell are aggregated, the method comprising:

receiving first downlink control information (DCI) for uplink transmit power control (TPC) through the first serving cell which is a primary cell for the terminal;

controlling transmit power of the SRS to be transmitted through the second serving cell based on a second TPC command for the terminal among a plurality of first TPC commands included in the first DCI when a carrier indicator (CI) included in the first DCI represents the second serving cell which is a secondary cell for the terminal; and

transmitting the SRS to the second serving cell using the controlled transmit power of the SRS.

11. The method of claim 10, wherein the CI is located before or after the plurality of first TPC commands, and

when the CI is located before the plurality of first TPC commands and each of the first TPC commands is 2 bits, the first DCI further comprises a padding bit between the CI and the plurality of first TPC commands according to whether the number of bits constituting the CI is an odd number.

12. The method of claim 10, wherein a payload size of the first DCI is equal to a payload size of one of a DCI format 3 and a DCI format 3A defined for a LTE (Long Term Evolution) system or a LTE-A (LTE-Advanced) system.

13. The method of claim 10, wherein the receiving of the first DCI comprises receiving the first DCI through a first common search space (CSS) for the first serving cell, and

the number of control channel elements (CCE) that the first CSS occupies is greater than 16 and is a multiple of 4 or 8.

14. The method of claim 10, wherein a payload size of the first DCI is equal to a payload size of a DCI format 1C defined for a LTE (Long Term Evolution) system or a LTE-A (LTE-Advanced) system.

15. The method of claim 14, wherein the receiving of the first DCI comprises receiving the first DCI through a first common search space (CSS) for the first serving cell, and

an aggregation level for the first CSS is 2.

16. The method of claim 10, further comprising:

receiving a second DCI for an uplink TPC through a first common search space (CSS) set to a physical downlink control channel (PDCCH) of the second serving cell; and

controlling transmit power of the SRS to be transmitted through the second serving cell based on a fourth TPC command for the terminal among a plurality of third TPC commands included in the second DCI.

17. The method of claim 16, wherein the number of control channel elements (CSS) for the first CSS is 8, and

the number of PDCCH candidates for the first CSS is 2 when an aggregation level is 4, while the number of PDCCH candidates for the first CSS is 1 when the aggregation level is 8.

18. A method for transmitting a physical uplink control channel (PUCCH) by a terminal in an environment in which a first carrier corresponding to a first serving cell and a second carrier corresponding to a second serving cell are aggregated, the method comprising:

receiving first downlink control information (DCI) for downlink scheduling through the second serving cell which is a secondary cell for the terminal;

controlling transmit power of the PUCCH based on a first TPC command for transmit power control (TPC) of the PUCCH included in the first DCI; and

transmitting the PUCCH to the second serving cell using the controlled transmit power of the PUCCH when the second serving cell among cells included in a first cell group is set as a cell through which the PUCCH is transmitted.

19. The method of claim 18, further comprising:

receiving a second DCI for an uplink TPC; and

controlling transmit power of the PUCCH based on a third TPC command for the terminal among a plurality of second TPC commands included in the second DCI when a carrier indicator (CI) included in the second DCI represents the second serving cell.

20. The method of claim 18, further comprising:

receiving a second DCI for an uplink TPC through a first common search space (CSS) set to a physical downlink control channel (PDCCH) of the second serving cell; and

controlling transmit power of the PUCCH based on a third TPC command for the terminal among a plurality of second TPC commands included in the second DCI.