Method and apparatus for random access
Various embodiments of the present disclosure provide a method for random access. The method which may be performed by a terminal device comprises determining a interlace configuration for uplink shared channel transmission to a network node in a two-step contention-free random access procedure. The method further comprises performing the uplink shared channel transmission to the network node in the two-step contention-free random access procedure, according to the determined interlace configuration. According to some embodiments of the present disclosure, the interlaced resource allocation for uplink shared channel transmission may be configured for a two-step contention-free random access procedure in a flexible and efficient way, so that the performance of the random access procedure can be improved.
1. A method performed by a terminal device, comprising:
determining an interlace configuration for uplink shared channel transmission to a network node in a two-step contention-free random access procedure; and
performing the uplink shared channel transmission to the network node in the two-step contention-free random access procedure, according to the determined interlace configuration; wherein the determination of the interlace configuration is based at least in part on dedicated signaling for the two-step contention-free random access procedure from the network node; wherein the dedicated signaling includes one or more of:
a start interlace index for an interlace or a set of interlaces allocated for the uplink shared channel transmission;
a number of consecutive interlaces allocated for the uplink shared channel transmission; and
a dedicated flag indicating whether to enable interlaced resource allocation for the uplink shared channel transmission in the two-step contention-free random access procedure.
2. The method according to claim 1 , wherein the determination of the interlace configuration is based at least in part on common signaling from the network node, and the common signaling indicates whether to enable interlaced resource allocation for the uplink shared channel transmission.
3. The method according to claim 1 , wherein the determination of the interlace configuration is based at least in part on one or more of:
first configuration information, which is related to a interlace configuration for uplink shared channel transmission of the terminal device in a two-step contention-based random access procedure; and
second configuration information, which is related to an interlace configuration for uplink shared channel transmission of the terminal device with configured grant based scheduling.
4. The method according to claim 3 , wherein the first configuration information is indicated by radio resource control signaling from the network node.
5. The method according to claim 3 , wherein the first configuration information is predetermined.
6. The method according to claim 1 , wherein the determination of the interlace configuration is based at least in part on one or more of the following messages from the network node:
a handover command message;
a beam failure recover message; and
a downlink control channel order for the two-step contention-free random access procedure.
7. A method performed by a network node, comprising:
determining an interlace configuration for uplink shared channel transmission of a terminal device in a two-step contention-free random access procedure; and
receiving the uplink shared channel transmission from the terminal device in the two-step contention-free random access procedure, according to the determined interlace configuration; transmitting dedicated signaling to the terminal device to indicate the determined interlace configuration; wherein the dedicated signaling includes one or more of:
a start interlace index for an interlace or a set of interlaces allocated for the uplink shared channel transmission;
a number of consecutive interlaces allocated for the uplink shared channel transmission; and
a dedicated flag indicating whether to enable interlaced resource allocation for the uplink shared channel transmission in the two-step contention-free random access procedure.
8. The method according to claim 7 , further comprising:
transmitting common signaling to the terminal device to indicate whether to enable interlaced resource allocation for the uplink shared channel transmission.
9. The method according to claim 7 , wherein the determination of the interlace configuration is based at least in part on one or more of:
first configuration information, which is related to an interlace configuration for uplink shared channel transmission of the terminal device in a two-step contention-based random access procedure; and
second configuration information, which is related to a interlace configuration for uplink shared channel transmission of the terminal device with configured grant based scheduling.
10. The method according to claim 9 , further comprising:
transmitting radio resource control signaling to the terminal device to indicate the first configuration information.
11. The method according to claim 9 , wherein the first configuration information is predetermined.
12. The method according to claim 7 , further comprising indicating the determined interlace configuration to the terminal device in one or more of the following messages:
a handover command message;
a beam failure recover message; and
a downlink control channel order for the two-step contention-free random access procedure.
13. A terminal device, comprising:
one or more processors; and
one or more memories comprising computer program codes,
the one or more memories and the computer program codes configured to, with the one or more processors, cause the terminal device at least to:
determine an interlace configuration for uplink shared channel transmission to a network node in a two-step contention-free random access procedure; and
perform the uplink shared channel transmission to the network node in the two-step contention-free random access procedure, according to the determined interlace configuration; wherein the determination of the interlace configuration is based at least in part on dedicated signaling for the two-step contention-free random access procedure from the network node; wherein the dedicated signaling includes one or more of:
a start interlace index for an interlace or a set of interlaces allocated for the uplink shared channel transmission;
a number of consecutive interlaces allocated for the uplink shared channel transmission; and
a dedicated flag indicating whether to enable interlaced resource allocation for the uplink shared channel transmission in the two-step contention-free random access procedure.
14. The terminal device according to claim 13 , wherein the determination of the interlace configuration is based at least in part on common signaling from the network node, and the common signaling indicates whether to enable interlaced resource allocation for the uplink shared channel transmission.
15. The terminal device according to claim 13 , wherein the determination of the interlace configuration is based at least in part on one or more of:
first configuration information, which is related to an interlace configuration for uplink shared channel transmission of the terminal device in a two-step contention-based random access procedure; and
second configuration information, which is related to a interlace configuration for uplink shared channel transmission of the terminal device with configured grant based scheduling.
16. The terminal device according to claim 15 , wherein the first configuration is indicated by radio resource control signaling from the network node.
17. The terminal device according to claim 16 , wherein the first configuration information is predetermined.
18. The terminal device according to claim 17 , wherein the determination of the interlace configuration is based at least in part on one or more of the following messages from the network node:
a handover command message;
a beam failure recover message; and
a downlink control channel order for the two-step contention-free random access procedure.