Method and user equipment for transmitting random access channel signal, and method and base station for receiving random access channel signal

• US 10,631,341 B2
• Filed: 04/27/2018
• Issued: 04/21/2020
• Est. Priority Date: 05/03/2017
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Eunsun, Ko, Hyunsoo, Kim, Kijun, Yoon, Sukhyon
• Primary Examiner(s): Aghdam, Freshteh N
• Application Number:
  US16/065,443
• Publication Number:
  US 20200053785A1
• Time in Patent Office: 725 Days
• CPC Class Codes: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713
• CPC Class Codes: H04J 13/0062 Zadoff-Chu
• CPC Class Codes: H04L 27/26 Systems using multi-frequency codes H04L27/32 takes precedence
• CPC Class Codes: H04L 27/2607 Cyclic extensions
• CPC Class Codes: H04L 27/261 Details of reference signals
• CPC Class Codes: H04L 27/2692 with preamble design, i.e. with negotiation of the synchronisation sequence with transmitter or sequence linked to the algorithm used at the receiver
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network
• CPC Class Codes: H04W 74/08 Non-scheduled access, e.g. ALOHA hybrid access H04W74/02
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

A user equipment in a wireless communication system receives RACH configuration information including preamble format information indicating a first format and transmits a RACH preamble with the first format. The RACH preamble with the first format includes a cyclic prefix (CP) part and a sequence part in a time domain. The RACH preamble with the first format satisfies: a CP length of the RACH preamble of the first format is N times a CP length N_CP of an orthogonal frequency division multiplexing (OFDM) symbol, where N is the number of OFDM symbols used to transmit a RACH preamble and is greater than 1.

Claims

1. A method of transmitting a random access channel (RACH) preamble by a user equipment in a wireless communication system, the method comprising:

receiving information on a configuration including preamble format information indicating a first format for the RACH preamble; and

transmitting the RACH preamble in N orthogonal frequency division multiplexing (OFDM) symbols based on the first format for the RACH preamble,

wherein the first format for the RACH preamble includes only a cyclic prefix (CP) part and a sequence part in a time domain, and

wherein the first format for the RACH preamble satisfies;

a length of the CP part is equal to N*N_CP, where N is greater than 1 and N_CP is a CP length of an OFDM symbol, and

the length of the CP part plus a length of the sequence part is equal to a total length of the N OFDM symbols.

2. The method according to claim 1,

wherein the length of the CP part is N*144*T_s and the length of the sequence part is N*2048*T_s, where T_s is a sampling time.

3. The method according to claim 2,

wherein 144*T_s is equal to N_CP and 2048*T_s is equal to a length of a data part per OFDM symbol.

4. The method according to claim 1,

wherein N is 2, 4, or 6.

5. The method according to claim 1,

wherein the sequence part includes a preamble sequence with a sequence length of 139 N times.

6. The method according to claim 1,

wherein the information on the configuration further includes information on a slot used for a RACH,

wherein when the preamble format information indicates a combination of the first format and a second format, the user equipment transmits the RACH preamble with the first format in a RACH resource associated with a synchronization signal (SS) block detected by the user equipment among RACH resources of the slot if the associated RACH resource is not a last RACH resource of the slot in the time domain and transmits a RACH preamble with the second format in the associated RACH resource if the associated RACH resource is the last RACH resource of the slot, and

wherein the second format includes a guard time with no signal after a sequence part of the second format.

7. A user equipment for transmitting a random access channel (RACH) preamble in a wireless communication system, the user equipment comprising,

a transceiver, and

a processor configured to control the transceiver, the processor configured to:

control the transceiver to receive information on a configuration including preamble format information indicating a first format for the RACH preamble; and

control the transceiver to transmit the RACH preamble in N orthogonal frequency division multiplexing (OFDM) symbols based on the first format for the RACH preamble,

wherein the first format for the RACH preamble includes only a cyclic prefix (CP) part and a sequence part in a time domain, and

wherein the first format for the RACH preamble satisfies;

a length of the CP part is equal to N*N_CP, where N is greater than 1 and N_CP is a CP length of an OFDM symbol, and

the length of the CP part plus a length of the sequence part is equal to a total length of the N OFDM symbols.

8. The user equipment according to claim 7,

wherein the length of the CP part is N*144*T_s and the length of the sequence part is N*2048*T_s, where T_s is a sampling time.

9. The user equipment according to claim 7,

wherein the information on the configuration further includes information on a slot used for a RACH,

wherein when the preamble format information indicates a combination of the first format and a second format, the processor controls the transceiver to transmit the RACH preamble with the first format in a RACH resource associated with a synchronization signal (SS) block detected by the user equipment among RACH resources of the slot if the associated RACH resource is not a last RACH resource of the slot in the time domain and controls the transceiver to transmit a RACH preamble with the second format in the associated RACH resource if the associated RACH resource is the last RACH resource of the slot, and

the second format includes a guard time with no signal after a sequence part of the second format.

10. A method of receiving a random access channel (RACH) preamble by a base station in a wireless communication system, the method comprising:

transmitting information on a configuration including preamble format information indicating a first format for the RACH preamble; and

detecting the RACH preamble in N orthogonal frequency division multiplexing (OFDM) symbols based on the first format for the RACH preamble,

wherein the first format for the RACH preamble includes only a cyclic prefix (CP) part and a sequence part in a time domain, and

wherein the first format for the RACH preamble satisfies;

a length of the CP part is equal to N*N_CP, where N is greater than 1 and N_CP is a CP length of an OFDM symbol, and

the length of the CP part plus a length of the sequence part is equal to a total length of the N OFDM symbols.

11. The method according to claim 10,

wherein the length of the CP part is N*144*T_s and the length of the sequence part is N*2048*T_s, where T_s is a sampling time.

12. The method according to claim 10,

wherein the sequence part includes a preamble sequence with a sequence length of 139 N times.

13. A base station for receiving a random access channel (RACH) preamble in a wireless communication system, the base station comprising,

a transceiver, and

a processor configured to control the transceiver, the processor configured to:

control the transceiver to transmit information on a configuration including preamble format information indicating a first format for the RACH format; and

detect the RACH preamble in N orthogonal frequency division multiplexing (OFDM) symbols based on the first format for the RACH preamble,

wherein the first format for the RACH preamble includes only a cyclic prefix (CP) part and a sequence part in a time domain, and

wherein the first format for the RACH preamble satisfies;

a length of the CP part is equal to N*N_CP, where N is greater than 1 and N_CP is a CP length of an OFDM symbol, and

the length of the CP part plus a length of the sequence part is equal to a total length of the N OFDM symbols.

14. The base station according to claim 13,

wherein the length of the CP part is N*144*T_s and the length of the sequence part is N*2048*T_s, where T_s is a sampling time.