APPARATUS AND METHOD FOR TRANSMISSION OF UPLINK SOUNDING REFERENCE SIGNALS IN A WIRELESS NETWORK

• US 20120039273A1
• Filed: 08/08/2011
• Published: 02/16/2012
• Est. Priority Date: 08/12/2010
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Nam, Young-Han, Zhang, Jianzhong
• Granted Patent: US 9,131,457 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 5/0005 Time-frequency
• 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: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/281 taking into account user or data type priority
• 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 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 72/00 Local resource management
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network

Abstract

A mobile station for use in a wireless network that operates according to the Long-Term Evolution Advanced (LTE-A) standard. The mobile station is operable to transmit an aperiodic sounding reference signal (SRS) to a base station in response to a triggering grant received from the base station. The bandwidth on which the mobile station transmits the aperiodic SRS depends on a type of the triggering grant. The type of the triggering grant is one of a downlink grant, an uplink multiple-input, multiple-output (MIMO) grant, and an uplink single-input, multiple-output (SIMO) grant.

Claims

1. A mobile station for use in a wireless network that operates according to the Long-Term Evolution Advanced standard, the mobile station operable to transmit a sounding reference signal in a SC-FDM symbol, wherein the sounding reference signal is transmitted on at least two component carriers and wherein if the total transmit power of the SC-FDM symbol associated with the sounding reference signal exceeds a maximum transmit power level, P_CMAX, of the mobile station, the mobile station scales the transmit power level of each of the at least two component carriers on which the sounding reference signal is transmitted.

2. The mobile station as set forth in claim 1, wherein the mobile station scales the transmit power level of the each of the at least two component carriers on which the sounding reference signal is transmitted according to the equation:

3. The mobile station as set forth in claim 1, wherein the sounding reference signal is transmitted aperiodically.

4. For use in a wireless network that operates according to the Long-Term Evolution Advanced standard, a method in a mobile station for transmitting a sounding reference signal in a SC-FDM symbol, wherein the sounding reference signal is transmitted on at least two component carriers, the method comprising:

determining if the total transmit power of the SC-FDM symbol associated with the sounding reference signal exceeds a maximum transmit power, P_CMAX, of the mobile station; and

in response to a determination that the total transmit power level exceeds P_CMAX, scaling the transmit power level of each of the at least two component carriers on which the sounding reference signal is transmitted.

5. The method as set forth in claim 4, wherein scaling the transmit power level comprises scaling the transmit power level of the each of the at least two component carriers on which the sounding reference signal is transmitted according to the equation:

6. The method as set forth in claim 5, wherein the sounding reference signal is transmitted aperiodically.

7. A mobile station for use in a wireless network that operates according to the Long-Term Evolution Advanced standard, the mobile station operable to transmit an aperiodic sounding reference signal (SRS) to a base station in response to a triggering grant received from the base station, wherein the bandwidth on which the mobile station transmits the aperiodic SRS depends on a type of the triggering grant, wherein the type of the triggering grant is one of a downlink grant, an uplink multiple-input, multiple-output (MIMO) grant, and an uplink single-input, multiple-output (SIMO) grant.

8. The mobile station as set forth in claim 7, wherein:

if the downlink grant triggers the aperiodic SRS, the mobile station transmits the aperiodic SRS in a first bandwidth;

if the uplink MIMO grant triggers the aperiodic SRS, the mobile station transmits the aperiodic SRS in a second bandwidth; and

if the uplink SIMO grant triggers the SRS, the mobile station transmits the aperiodic SRS in a third bandwidth.

9. The mobile station as set forth in claim 8, wherein the first, second and third bandwidths are configured by radio resource control (RRC) layer signals received from the base station.

10. For use in a wireless network that operates according to the Long-Term Evolution Advanced standard, a method in a mobile station for transmitting an aperiodic sounding reference signal (SRS) to a base station, the method comprising:

receiving from the base station a triggering grant; and

determining a bandwidth on which the mobile station transmits the aperiodic SRS according to a type of the triggering grant, wherein the type of the triggering grant is one of a downlink grant, an uplink multiple-input, multiple-output (MIMO) grant, and an uplink single-input, multiple-output (SIMO) grant.

11. The method as set forth in claim 10, further comprising:

if the downlink grant triggers the aperiodic SRS, transmitting the aperiodic SRS in a first bandwidth;

if the uplink MIMO grant triggers the aperiodic SRS, transmitting the aperiodic SRS in a second bandwidth; and

if the uplink SIMO grant triggers the aperiodic SRS, transmitting the aperiodic SRS in a third bandwidth.

12. The method as set forth in claim 11, wherein the first, second and third bandwidths are configured by radio resource control (RRC) layer signals received from the base station.

13. For use in a wireless network that operates according to the Long-Term Evolution Advanced standard, a base station operable to receive an aperiodic sounding reference signal (SRS) from a mobile station, wherein the base station transmits a triggering grant to the mobile station and, in response, receives the aperiodic SRS on a bandwidth that depends on a type of the triggering grant, wherein the type of the triggering grant is one of a downlink grant, an uplink multiple-input, multiple-output (MIMO) grant, and an uplink single-input, multiple-output (SIMO) grant.

14. The base station as set forth in claim 13, wherein,

if the downlink grant triggers the aperiodic SRS, then the base station receives the aperiodic SRS in a first bandwidth;

if the uplink MIMO grant triggers the aperiodic SRS, then the base station receives the aperiodic SRS in a second bandwidth; and

if the uplink SIMO grant triggers the aperiodic SRS, then the base station receives the aperiodic SRS in a third bandwidth.

15. The base station as set forth in claim 14, wherein the first, second and third bandwidths are configured by radio resource control (RRC) layer signals received from the base station.

16. For use in a wireless network that operates according to the Long-Term Evolution Advanced standard, a method of operating a base station operable to receive an aperiodic sounding reference signal (SRS) from a mobile station, the method comprising:

transmitting a triggering grant to the mobile station; and

receiving the aperiodic SRS on a bandwidth that depends on a type of the triggering grant, wherein the type of the triggering grant is one of a downlink grant, an uplink multiple-input, multiple-output (MIMO) grant, and an uplink single-input, multiple-output (SIMO) grant.

17. The method as set forth in claim 16, wherein:

if the downlink grant triggers the aperiodic SRS, then receiving the aperiodic SRS comprises receiving the aperiodic SRS in a first bandwidth;

if the uplink MIMO grant triggers the aperiodic SRS, then receiving the aperiodic SRS comprises receiving the aperiodic SRS in a second bandwidth; and

if the uplink SIMO grant triggers the aperiodic SRS, then receiving the aperiodic SRS comprises receiving the aperiodic SRS in a third bandwidth.

18. The method as set forth in claim 17, wherein the first, second and third bandwidths are configured by radio resource control (RRC) layer signals received from the base station.

19. A mobile station for use in a wireless network that operates according to the Long-Term Evolution Advanced standard, the mobile station operable to transmit aperiodic sounding reference signals to a base station in response to triggering grants received from the base station, wherein if the mobile station receives a first triggering grant and a second triggering grant operable to trigger aperiodic sounding reference signals in a first subframe of a same component carrier, the mobile station transmits an aperiodic sounding reference signal only if the first and second triggering grants trigger aperiodic sounding reference signals for the same resources in the first subframe.

20. A method in a mobile station operable to transmit aperiodic sounding reference signals to a base station in response to triggering grants received from the base station, the method comprising:

receiving in the mobile station a first triggering grant operable to trigger a first aperiodic sounding reference signal in a first subframe of a first component carrier;

receiving in the mobile station a second triggering grant operable to trigger a second aperiodic sounding reference signal in the first subframe of the first component carrier;

determining if the first and second aperiodic sounding reference signals are associated with the same bandwidth resources in the first subframe; and

in response to a determination that the first and second aperiodic sounding reference signals are associated with the same resources in the first subframe, transmitting an aperiodic sounding reference signal.