Uplink Power Control for Dual and Multi Carrier Radio System

• US 20120106422A1
• Filed: 03/26/2010
• Published: 05/03/2012
• Est. Priority Date: 06/30/2009
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Hultell, Johan, Bergman, Johan
• Granted Patent: US 9,113,426 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: H04W 52/228 using past power values or information
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels
• CPC Class Codes: H04W 52/343 taking into account loading or congestion level
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity
• CPC Class Codes: H04W 52/44 in connection with interruption of transmission

Abstract

In a method and a device a time-varying back-off value is used whereby differences in cell load can be taken into account for a restricted time-period during which the information is believed to be valid. Also, other time-varying variables of interest for the initial DPCCH power setting of the secondary earner can be taken into account when setting the back-off value.

Claims

1-14. -14. (canceled)

15. A method of selecting transmit power in a user equipment used for physical uplink Control Channel and Data Channel on a secondary carrier used by the user equipment when transmitting data on the secondary carrier in a cellular radio system, the method comprising:

determining a time-varying back-off value for a power level of the uplink Control Channel and Data Channel; and

selecting the determined time-varying back-off value to update a transmit power of the uplink Control Channel and Data Channel.

16. The method according to claim 15, wherein the uplink Control Channel and Data Channel comprises a Dedicated Physical Control Channel.

17. The method according to claim 15, wherein determining the time-varying back-off value comprises receiving the time-varying back-off value in a message from the cellular radio system.

18. The method according to claim 15, wherein selecting the determined time-varying back-off value further comprises selecting two time-varying back-off values when the user equipment enters a CELL_DCH state.

19. The method according to claim 15, wherein the time-varying back-off value is used:

when the user equipment enters a CELL_DCH state and the user equipment subsequently receives a High Speed Shared Control Channel order for activation of a secondary uplink carrier from a radio base station;

or

when the user equipment is deactivated and subsequently reactivated and the elapsed time-duration between the deactivation and the reactivation is smaller than a threshold.

20. The method according to claim 15, wherein determining the time-varying back-off value comprises determining the time-varying back-off value based on a cell load.

21. A device for selecting transmit power in a user equipment used for physical uplink Control Channel and Data Channel on a secondary carrier used by the user equipment when transmitting data on the secondary carrier in a cellular radio system, the device comprising a processor configured to:

determine a time-varying back-off value for a power level of the uplink Control Channel and Data Channel; and

select the received time-varying back-off value to update a transmit power of the uplink Control Channel and Data Channel.

22. The device according to claim 21, wherein the uplink Control Channel and Data Channel comprises a Dedicated Physical Control Channel.

23. The device according to claim 21, wherein the processor is further configured to receive the time-varying back-off value in a message from the cellular radio system.

24. The device according to claim 21, wherein the processor is further configured to select two time-varying back-off values when the user equipment enters a CELL_DCH state.

25. The device according to of claim 21, wherein the processor is further configured to use the time-varying back-off value:

when the user equipment enters a CELL_DCH state and the user equipment subsequently receives a High Speed Shared Control Channel order for activation of a secondary uplink carrier from a radio base station;

or

when the user equipment is deactivated and subsequently reactivated and the elapsed time-duration between the deactivation and the reactivation is smaller than a threshold.

26. The device according to claim 21, wherein the processor is configured to determine the time-varying back-off value based on a cell load.

27. A method in a network node for generating a transmit power value for use in a user equipment used for physical uplink Control Channel and Data Channel on a secondary carrier used by the user equipment when transmitting data on the secondary carrier in a cellular radio system, the method comprising:

generating a time-varying back-off value for the uplink Control Channel and Data Channel power level; and

transmitting the time-varying back-off value to the user equipment.

28. A network node adapted to generate transmit power value for use in a user equipment used for physical uplink Control Channel and Data Channel on a secondary carrier used by the user equipment when transmitting data on the secondary carrier in a cellular radio system, the node comprising a processor configured to:

generate a time-varying back-off value for the uplink Control Channel and Data Channel power level; and

transmit the time-varying back-off value to the user equipment.