Wireless communication using multiple types of random access occasions
Certain aspects of the present disclosure provide techniques for supporting multiple types of random access occasions. A method that may be performed by a user equipment (UE) includes receiving, from a base station (BS), an indication of at least two types of random access occasions (ROs) including a first RO type and a second RO type for communicating in a first coverage area of the BS as part of a random access process for the UE to establish a connection with the BS in the first coverage area. The method further includes transmitting, to the BS, a preamble on an RO of one of the first RO type or the second RO type, wherein a preamble format of the preamble is based on whether the RO is of the first RO type or the second RO type.
1. A method of wireless communication at a user equipment (UE), comprising:
receiving, from a network entity, an indication of at least two types of random access occasions (ROs) including a first RO type and a second RO type for communicating in a first coverage area of the network entity as part of a random access process for the UE to establish a connection with the network entity in the first coverage area;
determining to transmit a preamble using the one of the first RO type or the second RO type based on a type of the UE, wherein the type of the UE indicates:
whether the UE is capable of determining information regarding one or more of a round-trip delay or a frequency shift for communication between the UE and the BS prior to transmitting the preamble; or
whether the UE has information regarding a location of the UE and a location of the BS; or
whether the UE supports a satellite based positioning system; and
transmitting, to the network entity, a preamble on an RO of one of the first RO type or the second RO type based on the determining, wherein a preamble format of the preamble is based on whether the RO is of the first RO type or the second RO type.
2. The method of claim 1 , wherein the first RO type corresponds to a first duration in time, a first frequency range, and a first periodicity; and wherein the second RO type corresponds to a second duration in time, a second frequency range, and a second periodicity.
3. The method of claim 1 , wherein ROs of the first RO type and ROs of the second RO type do not overlap in both frequency and time.
4. The method of claim 1 , wherein ROs of the first RO type and ROs of the second RO type at least partially overlap in both frequency and time.
5. The method of claim 1 , wherein the first coverage area comprises one of a cell of the network entity or a beam of a satellite corresponding to the network entity.
6. The method of claim 1 , wherein the first RO type is associated with a first preamble format indicating a first time duration for the preamble, and wherein the second RO type is associated with a second preamble format indicating a second time duration for the preamble that is different than the first time duration.
7. The method of claim 1 , wherein determining to transmit the preamble using the one of the first RO type or the second RO type based on the type of the UE comprises:
determining the preamble format based on the type of the UE and a mapping between preamble formats and types of UEs; and
determining the one of the first RO type or the second RO type is associated with the determined preamble format.
8. The method of claim 7 , further comprising receiving the mapping from the network entity.
9. The method of claim 1 , wherein:
the first RO type is associated with a first preamble format,
the second RO type is associated with a second preamble format,
the first preamble format and the second preamble format use Zadoff-Chu sequences, have a same sequence length, and a same subcarrier spacing,
the first preamble format has a first cyclic prefix length and the second preamble format has a second cyclic prefix length that is shorter than the first cyclic prefix length,
ROs of the second RO type are fully contained in ROs of the first RO type, and
the first preamble format uses a first set of roots for a corresponding Zadoff-Chu sequence and the second preamble format uses a second set of roots for a corresponding Zadoff-Chu sequence.
10. A method of wireless communication at a network entity, comprising:
transmitting an indication of at least two types of random access occasions (ROs) including a first RO type and a second RO type for communicating in a first coverage area of the network entity as part of a random access process for one or more user equipments (UEs) to establish a connection with the network entity in the first coverage area; and
receiving, from a UE, a preamble on an RO of one of the first RO type or the second RO type, wherein a preamble format of the preamble is based on whether the RO is of the first RO type or the second RO type and the preamble format is further based on a type of the UE, and wherein the type of the UE indicates:
whether the UE is capable of determining information regarding one or more of a round-trip delay or a frequency shift for communication between the UE and the BS prior to transmitting the preamble; or
whether the UE has information regarding a location of the UE and a location of the BS; or
whether the UE supports a satellite based positioning system.
11. The method of claim 10 , wherein the first RO type corresponds to a first duration in time, a first frequency range, and a first periodicity; and wherein the second RO type corresponds to a second duration in time, a second frequency range, and a second periodicity.
12. The method of claim 10 , wherein ROs of the first RO type and ROs of the second RO type do not overlap in both frequency and time.
13. The method of claim 10 , wherein ROs of the first RO type and ROs of the second RO type at least partially overlap in both frequency and time.
14. The method of claim 10 , wherein the first coverage area comprises one of a cell of the network entity or a beam of a satellite corresponding to the network entity.
15. The method of claim 10 , wherein the first RO type is associated with a first preamble format indicating a first time duration for the preamble, and wherein the second RO type is associated with a second preamble format indicating a second time duration for the preamble that is different than the first time duration.
16. The method of claim 10 , further comprising transmitting a mapping between preamble formats and types of UEs to the UE.
17. The method of claim 10 , wherein:
the first RO type is associated with a first preamble format,
the second RO type is associated with a second preamble format,
the first preamble format and the second preamble format use Zadoff-Chu sequences, have a same sequence length, and a same subcarrier spacing,
the first preamble format has a first cyclic prefix length and the second preamble format has a second cyclic prefix length that is shorter than the first cyclic prefix length,
ROs of the second RO type are fully contained in ROs of the first RO type, and
the first preamble format uses a first set of roots for a corresponding Zadoff-Chu sequence and the second preamble format uses a second set of roots for a corresponding Zadoff-Chu sequence.
18. A user equipment (UE) configured for wireless communications, comprising: a memory comprising computer-executable instructions; and a processor configured to execute the computer-executable instructions and cause the UE to:
receive, from a network entity, an indication of at least two types of random access occasions (ROs) including a first RO type and a second RO type for communicating in a first coverage area of the network entity as part of a random access process for the UE to establish a connection with the network entity in the first coverage area;
determining to transmit a preamble using the one of the first RO type or the second RO type based on a type of the UE, wherein the type of the UE indicates:
whether the UE is capable of determining information regarding one or more of a round-trip delay or a frequency shift for communication between the UE and the BS prior to transmitting the preamble; or
whether the UE has information regarding a location of the UE and a location of the BS; or
whether the UE supports a satellite based positioning system; and
transmit, to the network entity, a preamble on an RO of one of the first RO type or the second RO type based on the determining, wherein a preamble format of the preamble is based on whether the RO is of the first RO type or the second RO type.
19. The UE of claim 18 , wherein the first RO type corresponds to a first duration in time, a first frequency range, and a first periodicity; and wherein the second RO type corresponds to a second duration in time, a second frequency range, and a second periodicity.
20. The UE of claim 18 , wherein ROs of the first RO type and ROs of the second RO type do not overlap in both frequency and time.
21. A network entity configured for wireless communications, comprising: a memory comprising computer-executable instructions; and a processor configured to execute the computer-executable instructions and cause the network entity to:
transmit an indication of at least two types of random access occasions (ROs) including a first RO type and a second RO type for communicating in a first coverage area of the network entity as part of a random access process for one or more user equipments (UEs) to establish a connection with the network entity in the first coverage area; and
receive, from a UE, a preamble on an RO of one of the first RO type or the second RO type, wherein a preamble format of the preamble is based on whether the RO is of the first RO type or the second RO type and the preamble format is further based on a type of the UE, and wherein the type of the UE indicates:
whether the UE is capable of determining information regarding one or more of a round-trip delay or a frequency shift for communication between the UE and the BS prior to transmitting the preamble; or
whether the UE has information regarding a location of the UE and a location of the BS; or
whether the UE supports a satellite based positioning system.
22. The network entity of claim 21 , wherein the first RO type corresponds to a first duration in time, a first frequency range, and a first periodicity; and wherein the second RO type corresponds to a second duration in time, a second frequency range, and a second periodicity.