Method and user equipment for transmitting random access preamble, and method and base station for receiving random access preamble
A UE transmits a random access channel (RACH) preamble and a BS receives the RACH channel. The BS configures the RACH preamble to align boundaries of the RACH preamble with boundaries of OFDM symbols on which the RACH preamble is configured in the time domain. The UE generates/transmits the RACH preamble to align the boundaries of the RACH preamble with the boundaries of OFDM symbols on which the RACH preamble is configured in the time domain.
1. A method of transmitting a random access channel (RACH) preamble by a user equipment in a wireless communication system, the method comprising:
generating the RACH preamble; and
transmitting the RACH preamble on a RACH resource,
wherein the RACH resource corresponds to a plurality of orthogonal frequency division multiplexing (OFDM) symbols in a time domain,
wherein a length N RA of the RACH preamble is equal to a total length N RA,symbols of the plurality of OFDM symbols,
wherein the RACH preamble consists of one cyclic prefix (CP) part and one sequence part following the CP part in the time domain,
wherein the RACH preamble is accompanied by no guard time,
wherein the sequence part includes n preambles, each preamble having a length N u , and a length N SEQ of the sequence part is N u *n, where n is a positive integer,
wherein a length N CP,RA of the CP part is greater than a length of a CP portion of an OFDM symbol so as to satisfy N CP,RA +N SEQ =N RA,symbols , and
wherein the RACH preamble spans the plurality of OFDM symbols from start to end of the plurality of OFDM symbols in the time domain.
2. The method according to claim 1 , wherein N u is a fixed value.
3. The method according to claim 1 , further comprising:
receiving information on a random access preamble format, wherein the RACH preamble is generated in accordance with the random access preamble format.
4. The method according to claim 1 , wherein the wireless communication system is a system to which reception beamforming by a base station is applicable per OFDM symbol.
5. A method of receiving a random access channel (RACH) preamble by a base station in a wireless communication system, the method comprising:
transmitting RACH preamble configuration information; and
receiving the RACH preamble on a RACH resource based on the RACH preamble configuration information,
wherein the RACH resource corresponds to a plurality of orthogonal frequency division multiplexing (OFDM) symbols in a time domain,
wherein a length N RA of the RACH preamble is equal to a total length N RA,symbols of the plurality of OFDM symbols, and
wherein the RACH preamble consists of one cyclic prefix (CP) part and one sequence part following the CP part in the time domain,
wherein the RACH preamble is accompanied by no guard time,
wherein the sequence part includes n preambles, each preamble having a length N u , and a length N SEQ of the sequence part is N u *n, where n is a positive integer,
wherein a length N CP,RA of the CP part is greater than a length of a CP portion of an OFDM symbol so as to satisfy N CP,RA +N SEQ =N RA,symbols , and
wherein the RACH preamble spans the plurality of OFDM symbols from start to end of the plurality of OFDM symbols in the time domain.
6. The method according to claim 5 , wherein N u is a fixed value.
7. The method according to claim 5 ,
wherein the RACH preamble configuration information includes a random access preamble format, and
wherein the RACH preamble is received in accordance with the random access preamble format.
8. The method according to claim 5 , wherein the wireless communication system is a system to which reception beamforming by the base station is applicable per OFDM symbol.
9. A user equipment for transmitting a random access channel (RACH) preamble in a wireless communication system, the user equipment comprising,
a transceiver,
a processor, and
a memory operably connectable to the processor and storing instructions that, when executed, cause the processor to perform operations comprising:
generating the RACH preamble; and
transmitting, via the transceiver, the RACH preamble on a RACH resource,
wherein the RACH resource corresponds to a plurality of orthogonal frequency division multiplexing (OFDM) symbols in a time domain,
wherein a length N RA of the RACH preamble is equal to a total length N RA,symbols of the plurality of OFDM symbols following the CP part in the time domain,
wherein the RACH preamble consists of one cyclic prefix (CP) part and one sequence part,
wherein the RACH preamble is accompanied by no guard time,
wherein the sequence part includes n preambles, each preamble having a length N u , and a length N SEQ of the sequence part is N u *n, where n is a positive integer,
wherein a length N CP,RA of the CP part is greater than a length of a CP portion of an OFDM symbol so as to satisfy N CP,RA +N SEQ =N RA,symbols , and
wherein the RACH preamble spans the plurality of OFDM symbols from start to end of the plurality of OFDM symbols in the time domain.
10. The user equipment according to claim 9 , wherein N u is a fixed value.
11. The user equipment according to claim 9 , wherein the operations further comprise:
receiving, via the transceiver, information on a random access preamble format, and
generating the RACH preamble in accordance with the random access preamble format.
12. The user equipment according to claim 9 , wherein the wireless communication system is a system to which reception beamforming by a base station is applicable per OFDM symbol.
13. A base station for receiving a random access channel (RACH) preamble in a wireless communication system, the base station comprising,
a transceiver,
a processor, and
a memory operably connectable to the processor and storing instructions that, when executed, cause the processor to perform operations comprising:
transmitting, via the transceiver, RACH preamble configuration information; and
receiving, via the transceiver, the RACH preamble on a RACH resource based on the RACH preamble configuration information,
wherein the RACH resource corresponds to a plurality of orthogonal frequency division multiplexing (OFDM) symbols in a time domain,
wherein a length N RA of the RACH preamble is equal to a total length N RA,symbols of the plurality of OFDM symbols,
wherein the RACH preamble consists of one cyclic prefix (CP) part and one sequence part following the CP part in the time domain,
wherein the RACH preamble is accompanied by no guard time,
wherein the sequence part includes n preambles, each preamble having a length N u , and a length N SEQ of the sequence part is N u *n, where n is a positive integer,
wherein a length N CP,RA of the CP part is greater than a length of a CP portion of an OFDM symbol so as to satisfy N CP,RA +N SEQ =N RA,symbols , and
wherein the RACH preamble spans the plurality of OFDM symbols from start to end of the plurality of OFDM symbols in the time domain.
14. The base station according to claim 13 , wherein N u is a fixed value.
15. The base station according to claim 13 ,
wherein the RACH preamble configuration information includes a random access preamble format, and
wherein the operations further comprise: receiving, via the transceiver, the RACH preamble in accordance with the random access preamble format.
16. The base station according to claim 13 , wherein the wireless communication system is a system to which reception beamforming is applicable per OFDM symbol.