Random access in an ultra-large coverage cell using a single-bit timing advance identifier
Embodiments of the present invention disclose a random access method. In a scenario of an ultra-large coverage cell, the method includes: receiving a random access (RA) preamble sent by user equipment (UE); setting a timing advance T A and an R-bit identifier that are of the ultra-large coverage cell, where the R-bit identifier is used to indicate a time granularity of the timing advance T A or is used to indicate a value range of the timing advance T A ; and sending a random access (RA) response message to the UE, where the RA response message includes the timing advance T A and the R-bit identifier, and the ultra-large coverage cell is a cell with a coverage distance greater than 107 Km. Therefore, uplink time and downlink time are aligned when uplink signals sent by UEs in different positions in a cell arrive at a base station.
1. A random access apparatus for use in an ultra-large coverage cell, the apparatus comprising:
a receiver, configured to receive a random access (RA) preamble sent by user equipment (UE), wherein the UE is within a coverage distance of the ultra-large coverage cell;
a processor, configured to set a timing advance T A and a single range bit (R-bit) identifier that are of the ultra-large coverage cell after the receiver receives the RA preamble, wherein the R-bit identifier is used to indicate either a first or a second value range of the timing advance T A for a coverage distance of the ultra-large coverage cell;
a transmitter, configured to send an RA response message to the UE, wherein the RA response message comprises the timing advance T A and the R-bit identifier that are set by the processor; and
wherein the ultra-large coverage cell is a cell with a coverage distance greater than 107 Km, wherein the R-bit identifier is used to indicate a time granularity of the timing advance T A , and wherein the processor is configured to:
set the R-bit identifier to 1 in the random access response message, indicating that the time granularity of the timing advance T A is greater than 16 T S , wherein T S represents a basic timing unit; or
set the R-bit identifier to 0 in the random access response message, indicating that the time granularity of the timing advance T A is 16 T S .
2. The random access apparatus according to claim 1 , wherein the UE determines, based on positioning environment information, that a position of the UE in a current cell exceeds a coverage distance supported by a guard period (GP) of the RA preamble.
3. A random access apparatus for use in an ultra-large coverage cell, the apparatus comprising:
a receiver, configured to receive a random access (RA) preamble sent by user equipment (UE), wherein the UE is within a coverage distance of the ultra-large coverage cell;
a processor, configured to set a timing advance T A and a single range bit (R-bit) identifier that are of the ultra-large coverage cell after the receiver receives the RA preamble, wherein the R-bit identifier is used to indicate either a first or a second value range of the timing advance T A for a coverage distance of the ultra-large coverage cell;
a transmitter, configured to send an RA response message to the UE, wherein the RA response message comprises the timing advance T A and the R-bit identifier that are set by the processor; and
wherein the ultra-large coverage cell is a cell with a coverage distance greater than 107 Km, wherein the processor is configured to:
set the R-bit identifier to 1 in the random access response message, indicating the value range of the timing advance T A , wherein the value range is 0, 1, 2, . . . , a value greater than 1282; or
set the R-bit identifier to 0 in the random access response message, indicating the value range of the timing advance T A , wherein the value range is 0, 1, 2, . . . , 1282.
4. A random access apparatus for use in an ultra-large coverage cell, the apparatus comprising:
a transmitter, configured to send a random access (RA) preamble to a base station, wherein the apparatus is within a coverage area of the ultra-large coverage cell;
a receiver, configured to receive an RA response message sent by the base station, wherein the RA response message comprises a timing advance T A and a single range bit (R-bit) identifier, and the R-bit identifier is used to indicate either a first or a second value range of the timing advance T A for a coverage distance of the ultra-large coverage cell;
a processor, configured to adjust uplink transmission timing according to the timing advance T A received by the receiver and the time granularity of the timing advance T A or the value range of the timing advance T A indicated by the R-bit identifier;
wherein the transmitter is configured to send an uplink signal or data according to the uplink transmission timing adjusted by the processor; and
wherein the ultra-large coverage cell is a cell with a coverage distance greater than 107 Km, wherein the R-bit identifier is used to indicate a time granularity of the timing advance T A and wherein the receiver is configured to:
when the received R-bit identifier is 1, indicate that the time granularity of the timing advance T A is greater than 16 T S , wherein T S represents a basic timing unit; or
when the received R-bit identifier is 0, indicate that the time granularity of the timing advance T A is 16 T S .
5. A random access apparatus for use in an ultra-large coverage cell, the apparatus comprising:
a transmitter, configured to send a random access (RA) preamble to a base station, wherein the apparatus is within a coverage area of the ultra-large coverage cell;
a receiver, configured to receive an RA response message sent by the base station, wherein the RA response message comprises a timing advance T A and a single range bit (R-bit) identifier, and the R-bit identifier is used to indicate either a first or a second value range of the timing advance T A for a coverage distance of the ultra-large coverage cell;
a processor, configured to adjust uplink transmission timing according to the timing advance T A received by the receiver and the time granularity of the timing advance T A or the value range of the timing advance T A indicated by the R-bit identifier;
wherein the transmitter is configured to send an uplink signal or data according to the uplink transmission timing adjusted by the processor; and
wherein the ultra-large coverage cell is a cell with a coverage distance greater than 107 Km, wherein the receiver is configured to indicate the value range of the timing advance T A when the received R-bit identifier is 1, wherein the value range is 0, 1, 2, . . . , a value greater than 1282; or
when the R-bit identifier received by the receiver is 0, the value range of the timing advance T A is indicated, wherein the value range is 0, 1, 2, . . . , 1282.
6. A random access method for use in an ultra-large coverage cell, the method comprising:
receiving a random access (RA) preamble sent by user equipment (UE), wherein the UE is within a coverage distance of the ultra-large coverage cell;
setting a timing advance T A and a single range bit (R-bit) identifier that are of the ultra-large coverage cell, wherein the R-bit identifier is used to indicate either a first or a second value range of the timing advance T A for a coverage distance of the ultra-large coverage cell;
sending an RA response message to the UE, wherein the RA response message comprises the timing advance T A and the R-bit identifier; and
wherein the ultra-large coverage cell is a cell with a coverage distance greater than 107 Km, wherein the R-bit identifier is used to indicate a time granularity of the timing advance T A and wherein setting an R-bit identifier of the ultra-large coverage cell comprises:
setting the R-bit identifier to 1 in the random access response message, indicating that the time granularity of the timing advance T A is greater than 16 T S , wherein T S represents a basic timing unit; or
setting the R-bit identifier to 0 in the random access response message, indicating that the time granularity of the timing advance T A is 16 T S .
7. A random access method for use in an ultra-large coverage cell, the method comprising:
receiving a random access (RA) preamble sent by user equipment (UE), wherein the UE is within a coverage distance of the ultra-large coverage cell;
setting a timing advance T A and a single range bit (R-bit) identifier that are of the ultra-large coverage cell, wherein the R-bit identifier is used to indicate either a first or a second value range of the timing advance T A for a coverage distance of the ultra-large coverage cell;
sending an RA response message to the UE, wherein the RA response message comprises the timing advance T A and the R-bit identifier; and
wherein the ultra-large coverage cell is a cell with a coverage distance greater than 107 Km, wherein setting an R-bit identifier of the ultra-large coverage cell comprises:
when the R-bit identifier is set to 1 in the random access response message, indicating the value range of the timing advance T A , wherein the value range is 0, 1, 2, . . . , a value greater than 1282; or
when the R-bit identifier is set to 0 in the random access response message, indicating the value range of the timing advance T A , wherein the value range is 0, 1, 2, . . . , 1282.
8. A random access method for use in an ultra-large coverage cell, the method comprising:
sending a random access (RA) preamble to a base station;
receiving an RA response message, wherein the RA response message comprises a timing advance T A and a single range bit (R-bit) identifier, and the R-bit identifier is used to indicate either a first or a second value range of the timing advance T A for a coverage distance of the ultra-large coverage cell;
adjusting uplink transmission timing according to the timing advance T A and the time granularity of the timing advance T A or the value range of the timing advance T A indicated by the R-bit identifier;
sending an uplink signal or data according to the adjusted uplink transmission timing; and
wherein the ultra-large coverage cell is a cell with a coverage distance greater than 107 Km, wherein the R-bit identifier is used to indicate a time granularity of the timing advance T A and wherein:
the received R-bit identifier is 1, indicating that the time granularity of the timing advance T A is greater than 16 T S , wherein T S represents a basic timing unit; or
the received R-bit identifier is 0, indicating that the time granularity of the timing advance T A is 16 T S .
9. A random access method for use in an ultra-large coverage cell, the method comprising:
sending a random access (RA) preamble to a base station;
receiving an RA response message, wherein the RA response message comprises a timing advance T A and a single range bit (R-bit) identifier, and the R-bit identifier is used to indicate either a first or a second value range of the timing advance T A for a coverage distance of the ultra-large coverage cell;
adjusting uplink transmission timing according to the timing advance T A and the time granularity of the timing advance T A or the value range of the timing advance T A indicated by the R-bit identifier;
sending an uplink signal or data according to the adjusted uplink transmission timing; and
wherein the ultra-large coverage cell is a cell with a coverage distance greater than 107 Km, wherein:
when the received R-bit identifier is 1, the value range of the timing advance T A is indicated, wherein the value range is 0, 1, 2, . . . , a value greater than 1282; or
when the received R-bit identifier is 0, the value range of the timing advance T A is indicated, wherein the value range is 0, 1, 2, . . . , 1282.