METHOD FOR CONTROLLING TRANSMISSION POWER OF SOUNDING REFERENCE SIGNAL IN WIRELESS COMMUNICATION SYSTEM AND APPARATUS FOR SAME

• US 20150016317A1
• Filed: 03/11/2013
• Published: 01/15/2015
• Est. Priority Date: 03/17/2012
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Park, Jonghyun, Kim, Hakseong, Yang, Suckchel, Seo, Hanbyul, Kim, Kijun, Kim, Byounghoon
• Granted Patent: US 9,591,583 B2
• Time in Patent Office: Days
• US Class Current: 370/280
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment
• 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: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04W 52/08 Closed loop power control
• CPC Class Codes: H04W 52/143 Downlink power control
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/16 Deriving transmission power values from another channel
• CPC Class Codes: H04W 52/247 where the output power of a terminal is based on a path parameter sent by another terminal
• CPC Class Codes: H04W 52/248 where transmission power control commands are generated based on a path parameter
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels
• CPC Class Codes: H04W 52/40 during macro-diversity or soft handoff
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

In the present invention, disclosed is a method for a terminal, which receives a downlink signal from a first base station and transmits an uplink signal to a second base station, transmitting a sounding reference signal (SRS) in a wireless communication system. More specifically, the method comprises the steps of: receiving from the first base station downlink control information including a triggering message of a first SRS; determining transmission power of the first SRS on the basis of the downlink control information; and transmitting the first SRS to the first base station with the transmission power that is determined, wherein a transmission power control command field, which is included in the downlink control information, is applied to a closed loop parameter for determining the transmission power of the first SRS.

Claims

1. A method for transmitting a sounding reference signal (SRS) by a terminal, the terminal receiving a downlink signal from a first base station and transmitting an uplink signal to a second base station in a wireless communication system, the method comprising:

receiving downlink control information including a triggering message for a first SRS from the first base station;

determining transmission power of the first SRS based on the downlink control information; and

transmitting the first SRS to the first base station with the determined transmission power,

wherein the downlink control information includes a transmission power control command field applied to a closed-loop parameter for the determination of the transmission power of the first SRS.

2. The method according to claim 1, wherein the first SRS is an SRS for acquisition of downlink channel state information.

3. The method according to claim 1, further comprising receiving offset information of the transmission power of the first SRS based on transmission power of an uplink data channel from a higher layer,

wherein the offset information reflects a difference in maximum transmission power between the first base station and the second base station.

4. The method according to claim 3, further comprising periodically transmitting a second SRS to the second base station.

5. The method according to claim 4, further comprising receiving offset information of transmission power of the second SRS based on the transmission power of the uplink data channel from the higher layer,

wherein the transmission power of the second SRS has a maximum offset less than a maximum offset of the first transmission power.

6. The method according to claim 1, wherein the downlink control information is received in a terminal-specific search space.

7. The method according to claim 1, wherein the transmission power control command field in the downlink control information is applied to a closed-loop parameter for determination of transmission power of an uplink data channel when the downlink control information is received in a common search space.

8. The method according to claim 1, wherein a resource allocation field in the downlink control information indicates absence of resource allocation, and at least one field associated with the resource allocation field is added to the transmission power control command field.

9. The method according to claim 1, wherein the wireless communication system is a time division duplex (TDD) system.

10. A terminal device in a wireless communication system comprising:

a reception module for receiving downlink control information including a triggering message for a first SRS from a first base station;

a processor for determining transmission power of the first SRS based on the downlink control information; and

a transmission module for transmitting the first SRS to the first base station with the determined transmission power,

wherein a transmission power control command field in the downlink control information is applied to a closed-loop parameter for the determination of the transmission power of the first SRS.

11. The terminal device according to claim 10, wherein the terminal device is positioned in an area in which a downlink signal is received from the first base station and an uplink signal is transmitted to a second base station.

12. The terminal device according to claim 11, wherein the transmission module periodically transmits a second SRS to the second base station.