METHOD AND USER EQUIPMENT FOR TRANSMITTING RANDOM ACCESS SIGNALS, AND METHOD AND BASE STATION FOR RECEIVING RANDOM ACCESS SIGNALS

• US 20190320430A1
• Filed: 11/06/2017
• Published: 10/17/2019
• Est. Priority Date: 11/06/2016
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Eunsun, Kim, Kijun, Ko, Hyunsoo, Yang, Suckchel, YI, Yunjung, Yoon, Sukhyon
• Granted Patent: US 10,873,929 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 27/2607 Cyclic extensions
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/26132 using repetition
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0035 Resource allocation in a cooperative multipoint environment
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/51 based on terminal or device properties
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access

Abstract

Disclosed herein are a method and apparatus for transmitting/receiving random access signals. A first random access channel (RACH) resource for a first RACH preamble format and a second RACH resource for a second RACH preamble format are configured, separately. The first RACH resource and the second RACH resource are for a UE at which Tx/Rx beam correspondence holds and for a UE at which Tx/Rx beam correspondence does not hold, respectively. A UE can use the first or second RACH resource, depending on whether or not Tx/Rx beam correspondence holds at the UE.

Claims

1. A method for transmitting, by a user equipment (UE), random access signals, the method comprising:

receiving, by the UE, configuration information of a first random access channel (RACH) resource for a first RACH preamble format and configuration information of a second RACH resource for a second RACH preamble format; and

transmitting, by the UE, a physical RACH (PRACH) with the first RACH preamble format on the first RACH resource or with the second RACH preamble format on the second RACH resource,

wherein the UE transmits the PRACH with the first RACH preamble format on the first RACH resource if transmission (Tx) and reception (Rx) (Tx/Rx) beam correspondence holds at the UE, and the UE transmits the PRACH with second RACH preamble format on the second RACH resource if Tx/Rx beam correspondence does not hold at the UE.

2. The method according to claim 1,

wherein the UE transmits the PRACH with the first RACH preamble format on the first RACH resource one time before a random access response (RAR) window if Tx/Rx beam correspondence holds at the UE, and the UE transmits the PRACH with the second RACH preamble format on the second RACH resource multiple times before the RAR window if Tx/Rx beam correspondence does not hold at the UE.

3. The method according to claim 2,

wherein the UE transmits the PRACH with the second RACH preamble format multiple times by changing Tx beam directions of the UE on the second RACH resource if Tx/Rx beam correspondence does not hold at the UE.

4. The method according to claim 1,

wherein the first or second RACH preamble format has a single preamble sequence, and at least one of a cyclic prefix preceding the single preamble sequence or a guard time following the single preamble sequence.

5. The method according to claim 1,

wherein the first or second RACH preamble format has multiple consecutive preamble sequences, and at least one of a cyclic prefix preceding the multiple consecutive preamble sequences or a guard time following the multiple consecutive preamble sequences.

6. A method for receiving, by a base station (BS), random access signals, the method comprising:

transmitting, by the BS, configuration information of a first random access channel (RACH) resource for a first RACH preamble format and configuration information of a second RACH resource for a second RACH preamble format; and

receiving, by the UE, a physical RACH (PRACH) with the first RACH preamble format on the first RACH resource or with the second RACH preamble format on the second RACH resource from a user equipment (UE),

wherein the BS receives the PRACH with the first RACH preamble format on the first RACH resource if transmission (Tx) and reception (Rx) (Tx/Rx) beam correspondence holds at the UE, and the BS receives the PRACH with second RACH preamble format on the second RACH resource if Tx/Rx beam correspondence does not hold at the UE.

7. The method according to claim 6,

wherein the BS attempts to receive the PRACH with one Rx beam direction if Tx/Rx beam correspondence holds at a transmission and reception point (TRP) of the BS, and the BS attempts to receive the PRACH by changing Rx beam directions if Tx/Rx beam correspondence holds at a transmission and reception point (TRP) of the BS.

8. The method according to claim 6,

wherein the first or second RACH preamble format has a single preamble sequence, and at least one of a cyclic prefix preceding the single preamble sequence or a guard time following the single preamble sequence.

9. The method according to claim 6,

wherein the first or second RACH preamble format has multiple consecutive preamble sequences, and at least one of a cyclic prefix preceding the multiple consecutive preamble sequences or a guard time following the multiple consecutive preamble sequences.

10. A user equipment (UE) for transmitting random access signals, the UE comprising:

a radio frequency (RF) unit, and

a processor configured to control the RF unit, the processor configured to;

control the RF unit to receive configuration information of a first random access channel (RACH) resource for a first RACH preamble format and configuration information of a second RACH resource for a second RACH preamble format; and

control the RF unit to transmit a physical RACH (PRACH) with the first RACH preamble format on the first RACH resource or with the second RACH preamble format on the second RACH resource,

wherein the processor is configured to control the RF unit to transmit the PRACH with the first RACH preamble format on the first RACH resource if transmission (Tx) and reception (Rx) (Tx/Rx) beam correspondence holds at the UE, and the processor is configured to control the RF unit to transmit the PRACH with second RACH preamble format on the second RACH resource if Tx/Rx beam correspondence does not hold at the UE.

11. The UE according to claim 10,

wherein the processor is configured to control the RF unit to transmit the PRACH with the first RACH preamble format on the first RACH resource one time before a random access response (RAR) window if Tx/Rx beam correspondence holds at the UE, and the processor is configured to control the RF unit to transmit the PRACH with the second RACH preamble format on the second RACH resource multiple times before the RAR window if Tx/Rx beam correspondence does not hold at the UE.

12. The UE according to claim 11,

wherein the processor is configured to control the RF unit to transmit the PRACH with the second RACH preamble format multiple times by changing Tx beam directions of the UE on the second RACH resource if Tx/Rx beam correspondence does not hold at the UE.

13. The UE according to claim 10,

wherein the first or second RACH preamble format has a single preamble sequence, and at least one of a cyclic prefix preceding the single preamble sequence or a guard time following the single preamble sequence.

14. The UE according to claim 10,

wherein the first or second RACH preamble format has multiple consecutive preamble sequences, and at least one of a cyclic prefix preceding the multiple consecutive preamble sequences or a guard time following the multiple consecutive preamble sequences.

15. A base station (BS) for receiving random access signals, the BS comprising:

a radio frequency (RF) unit, and

a processor configured to control the RF unit, the processor configured to;

control the RF unit to transmit configuration information of a first random access channel (RACH) resource for a first RACH preamble format and configuration information of a second RACH resource for a second RACH preamble format; and

control the RF unit to receive a physical RACH (PRACH) with the first RACH preamble format on the first RACH resource or with the second RACH preamble format on the second RACH resource from a user equipment (UE),

wherein the processor is configured to control the RF unit to receive the PRACH with the first RACH preamble format on the first RACH resource if transmission (Tx) and reception (Rx) (Tx/Rx) beam correspondence holds at the UE, and the processor is configured to control the RF unit to receive the PRACH with second RACH preamble format on the second RACH resource if Tx/Rx beam correspondence does not hold at the UE.

16. The BS according to claim 15,

wherein the processor is configured to control the RF unit to attempt to receive the PRACH with one Rx beam direction if Tx/Rx beam correspondence holds at a transmission and reception point (TRP) of the BS, and the processor is configured to control the RF unit to attempt to receive the PRACH by changing Rx beam directions if Tx/Rx beam correspondence holds at a transmission and reception point (TRP) of the BS.

17. The BS according to claim 15,

wherein the first or second RACH preamble format has a single preamble sequence, and at least one of a cyclic prefix preceding the single preamble sequence or a guard time following the single preamble sequence.

18. The BS according to claim 15,

wherein the first or second RACH preamble format has multiple consecutive preamble sequences, and at least one of a cyclic prefix preceding the multiple consecutive preamble sequences or a guard time following the multiple consecutive preamble sequences.