CONTROL CHANNEL OVERHEAD ASSUMPTIONS FOR DERIVING CSI FEEDBACK

• US 20140301293A1
• Filed: 03/26/2014
• Published: 10/09/2014
• Est. Priority Date: 04/05/2013
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Geirhofer, Stefan, Gaal, Peter, Chen, Wanshi
• Granted Patent: US 9,692,495 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0039 other detection of signalling, e.g. detection of TFCI explicit signalling H04L1/0046, H04L27/0012 and H04L25/0262 take precedence

Abstract

Determination of channel state information (CSI) feedback by mobile devices is disclosed in which the mobile device receives one or more configuration parameters, that may include one or more control channel parameters for configuring a mobile device control channel. The UE uses the configuration parameters to determine an assumption of overhead resources. Using this overhead assumption, the mobile device derives the CSI index and transmits the CSI index to a serving base station.

Claims

1. A method for wireless communication, comprising:

receiving, by a mobile device, one or more configuration parameters, comprising one or more control channel parameters for configuration of a control channel for the mobile device;

determining, by the mobile device, an overhead assumption based, at least in part, on the one or more configuration parameters;

deriving a channel state indicator (CSI) index based on the overhead assumption; and

transmitting the CSI index to a serving base station.

2. The method of claim 1, wherein the one or more configuration parameters includes identification of at least one of a plurality of sets of resources designated for the control channel, wherein the overhead assumption is determined based on the identified at least one of the plurality of sets of resources.

3. The method of claim 1, wherein the one or more configuration parameters includes identification of a search space type associated with a set of resources, wherein the overhead assumption is determined based on the set of resources associated with the identified search space type.

4. The method of claim 3, wherein the search space type includes one of:

a common search space; and

a mobile device-specific search space.

5. The method of claim 1, wherein the one or more configuration parameters includes identification of a subset of control channel resources excluded from determination of the overhead assumption, wherein the overhead assumption is determined based on a set of resources associated with the control channel excluding the identified subset of control channel resources.

6. The method of claim 1, wherein the one or more configuration parameters includes an identification of one of:

a localized control channel; and

a distributed control channel,

wherein the overhead assumption is determined, at least in part, based on the identification.

7. The method of claim 1, wherein the one or more configuration parameters include a configuration of a plurality of CSI processes,

wherein the determining the overhead assumption is performed separately for each of the plurality of CSI processes.

8. The method of claim 1, wherein CSI index includes a channel quality indicator (CQI) index and one or more of:

a rank indicator and a precoding matrix indicator (PMI).

9. The method of claim 1, further comprising:

receiving, at the mobile device, carrier configuration information configuring one of a plurality of component carriers, used for communication by the mobile device, for the control channel, wherein the overhead assumption by the mobile device is determined for the one of the plurality of component carriers configured for the control channel.

10. The method of claim 9, wherein the mobile device determines a zero overhead assumption for each of the other of the plurality of components carriers not configured for the control channel.

11. An apparatus configured for wireless communication, comprising:

means for receiving, by a mobile device, one or more configuration parameters, comprising one or more control channel parameters for configuration of a control channel for the mobile device;

means for determining, by the mobile device, an overhead assumption based, at least in part, on the one or more configuration parameters;

means for deriving a channel state indicator (CSI) index based on the overhead assumption; and

means for transmitting the CSI index to a serving base station.

12. The apparatus of claim 11, wherein the one or more configuration parameters includes identification of at least one of a plurality of sets of resources designated for the control channel, wherein the overhead assumption is determined based on the identified at least one of the plurality of sets of resources.

13. The apparatus of claim 11, wherein the one or more configuration parameters includes identification of a search space type associated with a set of resources, wherein the overhead assumption is determined based on the set of resources associated with the identified search space type.

14. The apparatus of claim 13, wherein the search space type includes one of:

a common search space; and

a mobile device-specific search space.

15. The apparatus of claim 11, wherein the one or more configuration parameters includes identification of a subset of control channel resources excluded from determination of the overhead assumption, wherein the overhead assumption is determined based on a set of resources associated with the control channel excluding the identified subset of control channel resources.

16. The apparatus of claim 11, wherein the one or more configuration parameters includes an identification of one of:

a localized control channel; and

a distributed control channel,

wherein the overhead assumption is determined, at least in part, based on the identification.

17. The apparatus of claim 11, wherein the one or more configuration parameters include a configuration of a plurality of CSI processes,

wherein the means for determining the overhead assumption are performed separately for each of the plurality of CSI processes.

18. The apparatus of claim 11, wherein CSI index includes a channel quality indicator (CQI) index and one or more of:

a rank indicator and a precoding matrix indicator (PMI).

19. The apparatus of claim 11, further comprising:

means for receiving, at the mobile device, carrier configuration information configuring one of a plurality of component carriers, used for communication by the mobile device, for the control channel, wherein the overhead assumption by the mobile device is determined for the one of the plurality of component carriers configured for the control channel.

20. The apparatus of claim 19, wherein the mobile device determines a zero overhead assumption for each of the other of the plurality of components carriers not configured for the control channel.

21. A computer program product for wireless communications in a wireless network, comprising:

a non-transitory computer-readable medium having program code recorded thereon, the program code including;

program code for causing a computer to receive, by a mobile device, one or more configuration parameters, comprising one or more control channel parameters for configuration of a control channel for the mobile device;

program code for causing a computer to determine, by the mobile device, an overhead assumption based, at least in part, on the one or more configuration parameters;

program code for causing a computer to derive a channel state indicator (CSI) index based on the overhead assumption; and

program code for causing a computer to transmit the CSI index to a serving base station.

22. The computer program product of claim 21, wherein the one or more configuration parameters includes identification of at least one of a plurality of sets of resources designated for the control channel, wherein the overhead assumption is determined based on the identified at least one of the plurality of sets of resources.

23. The computer program product of claim 21, wherein the one or more configuration parameters includes identification of a search space type associated with a set of resources, wherein the overhead assumption is determined based on the set of resources associated with the identified search space type.

24. The computer program product of claim 23, wherein the search space type includes one of:

a common search space; and

a mobile device-specific search space.

25. The computer program product of claim 21, wherein the one or more configuration parameters includes identification of a subset of control channel resources excluded from determination of the overhead assumption, wherein the overhead assumption is determined based on a set of resources associated with the control channel excluding the identified subset of control channel resources.

26. The computer program product of claim 21, wherein the one or more configuration parameters includes an identification of one of:

a localized control channel; and

a distributed control channel,

wherein the overhead assumption is determined, at least in part, based on the identification.

27. The computer program product of claim 21, wherein the one or more configuration parameters include a configuration of a plurality of CSI processes,

wherein the program code for causing a computer to determine the overhead assumption is executed separately for each of the plurality of CSI processes.

28. The computer program product of claim 21, wherein CSI index includes a channel quality indicator (CQI) index and one or more of:

a rank indicator and a precoding matrix indicator (PMI).

29. The computer program product of claim 21, further comprising:

program code for causing a computer to receive, at the mobile device, carrier configuration information configuring one of a plurality of component carriers, used for communication by the mobile device, for the control channel, wherein the overhead assumption by the mobile device is determined for the one of the plurality of component carriers configured for the control channel.

30. The computer program product of claim 29, wherein the mobile device determines a zero overhead assumption for each of the other of the plurality of components carriers not configured for the control channel.

31. An apparatus configured for wireless communication, the apparatus comprising:

at least one processor; and

a memory coupled to the at least one processor,

wherein the at least one processor is configured;

to receive, by a mobile device, one or more configuration parameters, comprising one or more control channel parameters for configuration of a control channel for the mobile device;

to determine, by the mobile device, an overhead assumption based, at least in part, on the one or more configuration parameters;

to derive a channel state indicator (CSI) index based on the overhead assumption; and

to transmit the CSI index to a serving base station.

32. The apparatus of claim 31, wherein the one or more configuration parameters includes identification of at least one of a plurality of sets of resources designated for the control channel, wherein the overhead assumption is determined based on the identified at least one of the plurality of sets of resources.

33. The apparatus of claim 31, wherein the one or more configuration parameters includes identification of a search space type associated with a set of resources, wherein the overhead assumption is determined based on the set of resources associated with the identified search space type.

34. The apparatus of claim 33, wherein the search space type includes one of:

a common search space; and

a mobile device-specific search space.

35. The apparatus of claim 31, wherein the one or more configuration parameters includes identification of a subset of control channel resources excluded from determination of the overhead assumption, wherein the overhead assumption is determined based on a set of resources associated with the control channel excluding the identified subset of control channel resources.

36. The apparatus of claim 31, wherein the one or more configuration parameters includes an identification of one of:

a localized control channel; and

a distributed control channel,

wherein the overhead assumption is determined, at least in part, based on the identification.

37. The apparatus of claim 31, wherein the one or more configuration parameters include a configuration of a plurality of CSI processes,

wherein the configuration of the at least one processor to determine the overhead assumption is performed separately for each of the plurality of CSI processes.

38. The apparatus of claim 31, wherein CSI index includes a channel quality indicator (CQI) index and one or more of:

a rank indicator and a precoding matrix indicator (PMI).

39. The apparatus of claim 31, further comprising configuration of the at least one processor:

to receive, at the mobile device, carrier configuration information configuring one of a plurality of component carriers, used for communication by the mobile device, for the control channel, wherein the overhead assumption by the mobile device is determined for the one of the plurality of component carriers configured for the control channel.

40. The apparatus of claim 39, wherein the mobile device determines a zero overhead assumption for each of the other of the plurality of components carriers not configured for the control channel.