UPLINK TRANSMISSION CONTROL WITH CLEAR CHANNEL ASSESSMENT

• US 20160286545A1
• Filed: 03/09/2016
• Published: 09/29/2016
• Est. Priority Date: 03/23/2015
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: LUO, Tao, DAMNJANOVIC, Aleksandar, SUN, Jing
• Granted Patent: US 10,524,236 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 74/08 Non-scheduled access, e.g. ALOHA hybrid access H04W74/02
• CPC Class Codes: H04W 74/0808 using carrier sensing, e.g. carrier sense multiple access [CSMA]
• CPC Class Codes: H04W 76/15 Setup of multiple wireless link connections

Abstract

A method, an apparatus, and a computer program product for wireless communication are provided. An eNB transmits pre-grant(s) to a UE(s) for a target resource on a contention-based carrier. In response, the UE(s) perform a CCA/eCCA and, when successful, transmit a preamble to the eNB based on the pre-grant. The eNB detects the preamble(s) and transmits grant confirmation(s) to the UE(s) for which a preamble was detected. The grant confirmation(s) may modify the pre-grant(s). The eNB may overschedule a target resource and based on the received preambles may transmit grant confirmation(s) that instruct a portion of the UEs for which a preamble was received to transmit data on a target resource and may instruct the remaining portion of the UEs for which a preamble was received to cease or modify data transmission.

Claims

1. A method of wireless communication, comprising:

receiving a pre-grant assignment at a user equipment (UE);

performing a clear channel assessment (CCA) operation on a secondary component carrier (SCC) based on the pre-grant assignment;

transmitting a preamble on the SCC based on the pre-grant assignment when the CCA operation succeeds, the preamble uniquely identifying the UE; and

receiving a grant confirmation in response to the preamble transmission.

2. The method of claim 1, wherein the grant confirmation comprises at least one of:

a grant confirmation of the pre-grant assignment;

a modification of the pre-grant assignment;

or

an indication to discontinue transmission.

3. The method of claim 1, wherein the preamble is transmitted on a contention based carrier,

wherein the pre-grant assignment comprises a target subframe in the SCC, and

wherein the UE transmits the preamble in the SCC identified in the pre-grant assignment.

4. The method of claim 1, wherein the preamble comprises an initial portion to identify the UE to a base station that issued the pre-grant assignment and a second portion for band occupation.

5. The method of claim 4, wherein a remaining portion of the preamble comprises a WiFi preamble.

6. The method of claim 1, wherein at least one of the pre-grant assignment or the grant confirmation is received on a primary component carrier (PCC).

7. An apparatus for wireless communication, comprising:

means for receiving a pre-grant assignment at a user equipment (UE);

means for performing a clear channel assessment (CCA) operation based on the pre-grant assignment;

means for transmitting a preamble based on the pre-grant assignment when the CCA operation succeeds, the preamble uniquely identifying the UE; and

means for receiving a grant confirmation in response to the preamble transmission.

8. The apparatus of claim 7, wherein the grant confirmation comprises at least one of:

a grant confirmation of the pre-grant assignment;

a modification of the pre-grant assignment;

or

an indication to discontinue transmission.

9. The apparatus of claim 7, wherein the pre-grant assignment comprises a target subframe in the SCC, and wherein the means for transmitting the preamble is configured to transmit the preamble in the SCC identified in the pre-grant assignment.

10. The apparatus of claim 7, wherein at least one of the pre-grant assignment or the grant confirmation is received on a primary component carrier (PCC).

11. An apparatus for wireless communication, comprising:

a memory; and

at least one processor coupled to the memory and configured to;

receive a pre-grant assignment at a user equipment (UE);

perform a clear channel assessment (CCA) operation based on the pre-grant assignment;

transmit a preamble based on the pre-grant assignment when the CCA operation succeeds, the preamble uniquely identifying the UE; and

receive a grant confirmation in response to the preamble transmission.

12. The apparatus of claim 11, wherein the grant confirmation comprises at least one of:

a grant confirmation of the pre-grant assignment;

a modification of the pre-grant assignment;

or

an indication to discontinue transmission.

13. The apparatus of claim 11, wherein the pre-grant assignment comprises a target subframe in the SCC, and

wherein the at least one processor is configured to transmit the preamble in the SCC identified in the pre-grant assignment.

14. The apparatus of claim 11, wherein at least one of the pre-grant assignment or the grant confirmation is received on a primary component carrier (PCC).

15. A computer-readable medium storing computer executable code for wireless communication, comprising code to:

receiving a pre-grant assignment at a user equipment (UE);

performing a clear channel assessment (CCA) operation based on the pre-grant assignment;

transmitting a preamble based on the pre-grant assignment when the CCA operation succeeds, the preamble uniquely identifying the UE; and

receiving a grant confirmation in response to the preamble transmission.

16. The computer-readable medium of claim 15, wherein the grant confirmation comprises at least one of:

a grant confirmation of the pre-grant assignment;

a modification of the pre-grant assignment;

or

an indication to discontinue transmission.

17. The computer-readable medium of claim 15, wherein the pre-grant assignment comprises a target subframe in the SCC and the preamble is transmitted in the SCC identified in the pre-grant assignment.

18. The computer-readable medium of claim 15, wherein at least one of the pre-grant assignment or the grant confirmation is received on a primary component carrier (PCC).

19. A method of wireless communication, comprising:

transmitting one or more pre-grant assignments to a set of user equipments (UEs), the set including one or more UE;

detecting one or more preamble transmissions on a contention based carrier in response to the transmission of the one or more pre-grant assignments; and

transmitting one or more grant confirmation assignments in response to the detected one or more preamble transmissions.

20. The method of claim 19,

wherein transmitting the one or more pre-grant assignments includes transmitting a plurality of pre-grant assignments to a plurality of UEs with assignments for the same resource;

wherein detecting the one or more preamble transmissions includes detecting a plurality of preamble transmissions in response to the transmitted pre-grant assignments, each preamble uniquely identifying one of the UEs, and further comprising;

determining a modification of the pre-grant assignments for UEs for which a preamble transmission is detected.

21. The method of claim 20, wherein determining the modification of the pre-grant assignments includes

determining at least one UE to receive a grant confirmation indicating that the UE should continue transmission;

and

determining other UEs for which preambles were received that should receive an indication to stop transmission.

22. The method of claim 21, wherein the grant confirmation comprises a modification of the pre-grant assignment.

23. The method of claim 19, wherein at least one of the one or more pre-grant assignments or the one or more grant confirmation assignments is transmitted on a primary component carrier (PCC).

24. An apparatus for wireless communication, comprising:

means for transmitting one or more pre-grant assignments to a set of user equipments (UEs), the set including one or more UE;

means for detecting one or more preamble transmissions on a contention based carrier in response to the transmission of the one or more pre-grant assignments; and

means for transmitting one or more grant confirmation assignments in response to the detected one or more preamble transmissions.

25. The apparatus of claim 24,

wherein the means for transmitting the one or more pre-grant assignments is configured to transmit a plurality of pre-grant assignments to a plurality of UEs with assignments for the same resource;

wherein the means for detecting the one or more preamble transmissions is configured to detect a plurality of preamble transmissions in response to the transmitted pre-grant assignments, each preamble uniquely identifying one of the UEs, and the apparatus further comprising;

means for determining a modification of the pre-grant assignments for UEs for which a preamble transmission is detected, the means for determining a modification of the pre-grant assignments being configured to;

determine at least one UE to receive a grant confirmation indicating that the UE should continue transmission; and

determine other UEs for which preambles were received that should receive an indication to stop transmission.

26. The apparatus of claim 24, wherein at least one of the one or more pre-grant assignments or the one or more grant confirmation assignments is transmitted on a primary component carrier (PCC).

27. An apparatus for wireless communication, comprising:

a memory; and

at least one processor coupled to the memory and configured to;

transmit one or more pre-grant assignments to a set of user equipments (UEs), the set including one or more UE;

detect one or more preamble transmissions on a contention based carrier in response to the transmission of the one or more pre-grant assignments; and

transmit one or more grant confirmation assignments in response to the detected one or more preamble transmissions.

28. The apparatus of claim 27, wherein the at least one processor is further configured to:

transmit a plurality of pre-grant assignments to a plurality of UEs with assignments for the same resource and to detect a plurality of preamble transmissions in response to the transmitted pre-grant assignments, each preamble uniquely identifying one of the UEs; and

determine a modification of the pre-grant assignments for UEs for which a preamble transmission is detected, wherein determining a modification of the pre-grant assignments includes;

determining at least one UE to receive a grant confirmation indicating that the UE should continue transmission; and

determining other UEs for which preambles were received that should receive an indication to stop transmission.

29. The apparatus of claim 27, wherein at least one of the one or more pre-grant assignments or the one or more grant confirmation assignments is transmitted on a primary component carrier (PCC).

30. A computer-readable medium storing computer executable code, comprising code to:

transmit one or more pre-grant assignments to a set of user equipments (UEs), the set including one or more UE;

detect one or more preamble transmissions on a contention based carrier in response to the transmission of the one or more pre-grant assignments; and

transmit one or more grant confirmation assignments in response to the detected one or more preamble transmissions.

31. The computer-readable medium of claim 30, further comprising code to:

transmit a plurality of pre-grant assignments to a plurality of UEs with assignments for the same resource;

detect a plurality of preamble transmissions in response to the transmitted pre-grant assignments, each preamble uniquely identifying one of the UEs; and

determine a modification of the pre-grant assignments for UEs for which a preamble transmission is detected, wherein determining a modification of the pre-grant assignments includes;

determine at least one UE to receive a grant confirmation indicating that the UE should continue transmission; and

determine other UEs for which preambles were received that should receive an indication to stop transmission.

32. The computer-readable medium of claim 30, wherein at least one of the one or more pre-grant assignments or the one or more grant confirmation assignments is transmitted on a primary component carrier (PCC).