Robust Control Channel Transmission Scheme

• US 20180227887A1
• Filed: 01/17/2018
• Published: 08/09/2018
• Est. Priority Date: 02/06/2017
• Status: Active Grant

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Technologies Oy (Nokia Corporation)
• Inventors: Hakola, Sami-Jukka, TIIROLA, Esa T., ENESCU, Mihai, KAIKKONEN, Jorma, KARJALAINEN, Juha P.
• Granted Patent: US 10,484,983 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 7/022 Site diversity; Macro-diversity using two or more spaced independent antennas H04B7/04
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0695 using beam selection
• CPC Class Codes: H04W 72/046 the resource being in the space domain, e.g. beams
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

Signaling is received (or transmitted) to configure a UE with multiple transmit beams, each for receiving beam-specific DCI. A beam-specific current DCI is received at the UE (or transmitted from a network) on the transmit beam(s), including information about beam-specific previous DCIs transmitted to the UE on any of the multiple transmit beams within a predefined time window preceding a time unit in which the current DCI was received. Information about the beam-specific previous DCIs is used to determine that at least one of the multiple transmit beams has been blocked. Each of the multiple transmit beams that have been determined to be blocked is reported to (and received by) the network. In response to receiving from the UE a report indicating at least one multiple transmit beams has been blocked, the network reconfigures the UE with a different set of multiple transmit beams each for beam-specific DCI.

Claims

1. An apparatus comprising at least one processor and at least one memory tangibly storing a computer program;

wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to;

receive signaling to configure a user equipment (UE) with multiple transmit beams each for receiving beam-specific downlink control information (DCI);

receive a beam-specific current DCI at the UE on at least one of the transmit beams, said received current DCI including information about beam-specific previous DCIs transmitted to the UE on any of the multiple transmit beams within a predefined time window preceding a time unit in which the current DCI was received;

use the information about the beam-specific previous DCIs to determine that at least one of the multiple transmit beams has been blocked; and

report each of the multiple transmit beams that have been determined to be blocked.

2. The apparatus according to claim 1, wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to:

use the information about the beam-specific previous DCIs to determine that at least one of the multiple transmit beams has been blocked, and

determine from the information that reception by the UE of at least a predefined minimum number of the previous DCIs transmitted to the UE on any given one of the multiple transmit beams within the predefined time window has failed.

3. The apparatus according to claim 1, wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to:

send a beam status information report that identifies each of the multiple transmit beams that have been determined to be blocked.

4. The apparatus according to claim 1, wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to:

send on a preconfigured uplink resource that corresponds to one of the non-blocked multiple transmit beams and is for reporting beam status information only if said preconfigured resource is within a predefined maximum number of time units from said determining;

else

send on an uplink resource obtained by the UE in response to an uplink resource request sent by the UE after the at least one of the multiple transmit beams was determined to have been blocked.

5. The apparatus according to claim 1, wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus report in part of a beam recovery procedure in which the UE receives a beam re-configuration.

6. The apparatus according to claim 5, wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to:

between the reporting and the UE receiving the beam reconfiguration, monitor for beam-specific further DCI on the multiple transmit beam or beams which were not determined to have been blocked.

7. The apparatus according to claim 6, wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to select the beam recovery procedure from among at least a first and a second procedure according to predetermined prioritization rules if the UE has a preconfigured uplink resource allocated for a periodic beam status report within a predefined maximum number of time units from said determining.

8. The apparatus according to claim 7, wherein the pre-determined prioritization rules comprise:

select the first beam recovery procedure if an uplink beam corresponding to the preconfigured uplink resource is associated to one of the multiple transmit beams that have been determined to be blocked;

else

select the second beam recovery procedure if an uplink beam corresponding to the preconfigured uplink resource is associated to any of the multiple transmit beams that have not been determined to be blocked.

9. The apparatus according to claim 1, wherein:

the multiple transmit beams are associated to at least two different transmit-receive points; and

wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to

receive signal reference power from each of the transmit-receive points and to use with the information about the beam-specific previous DCIs to determine that at least one of the multiple transmit beams has been blocked.

10. The apparatus according to claim 1, wherein the information about the beam-specific previous DCIs indicates a count of such DCIs over the multiple transmit beams, or a beam-specific count for at least some of the multiple transmit beams.

11. The apparatus according to claim 10, wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to receive each of the beam-specific DCIs on physical downlink control channel (PDCCH), and the count is at least one of:

previous PDCCHs that allocate a downlink resource to the UE, and previous PDCCHs that allocate to the UE a downlink resource and/or an uplink resource.

12. The apparatus according to claim 1, wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to trigger the reporting using at least one of a physical random access channel (PRACH) and a physical uplink control channel (PUCCH).

13. The apparatus according to claim 1, wherein the information about the beam-specific previous DCIs transmitted to the UE is received in the beam-specific current DCI which comprises at least one of:

a DCI specific to the UE; and

a DCI common to multiple UEs.

14. The apparatus according to claim 1, wherein said received current DCI including information about all beam-specific previous DCIs transmitted to the UE on any of the multiple transmit beams within a predefined time window preceding a time unit in which the current DCI was received.

15. A method comprising:

receiving signaling to configure a user equipment (UE) with multiple transmit beams each for receiving beam-specific downlink control information (DCI);

receiving a beam-specific current DCI at the UE on at least one of the transmit beams, said received current DCI including information about beam-specific previous DCIs transmitted to the UE on any of the multiple transmit beams within a predefined time window preceding a time unit in which the current DCI was received;

using the information about the beam-specific previous DCIs to determine that at least one of the multiple transmit beams has been blocked; and

reporting each of the multiple transmit beams that have been determined to be blocked.

16. An apparatus comprising at least one processor and at least one memory tangibly storing a computer program;

wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to;

configure a user equipment (UE) with multiple transmit beams each for receiving beam-specific downlink control information (DCI);

transmit to the UE a beam-specific current DCI on at least one of the transmit beams, said transmitted current DCI including information about beam-specific previous DCIs transmitted to the UE on any of the multiple transmit beams within a predefined time window preceding a time unit in which the current DCI was received; and

in response to receiving from the UE a report indicating at least one multiple transmit beams has been determined to be blocked, reconfigure the UE with a different set of multiple transmit beams each for beam-specific DCI.

17. The apparatus according to claim 16, wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to receive the report from the UE on one of:

a preconfigured uplink resource that corresponds to one of the non-blocked multiple transmit beams; and

an uplink resource obtained by the UE in response to an uplink resource request received from the UE after the report has been received.

18. The apparatus according to claim 16, wherein the at least one processor is configured with the at least one memory and the computer program to cause the apparatus to:

between receiving the report and re-configuring the UE, restrict transmission of beam-specific further DCI for the UE to the multiple transmit beam or beams which the report does not indicate have been determined to be blocked.

19. The apparatus according to claim 16, wherein the information about the beam-specific previous DCIs indicates a count of such DCIs over the multiple transmit beams, or a beam-specific count for at least some of the multiple transmit beams.

20. The apparatus according to claim 16, wherein the information about the beam-specific previous DCIs transmitted to the UE is transmitted in the beam-specific current DCI which comprises at least one of:

a DCI specific to the UE; and

a DCI common to multiple UEs.