US 2023/0156804 A1 · RACH PROCEDURES FOR NON-TERRESTRIAL NETWORKS FOR USER EQUIPMENT

Abstract

Methods and systems to enhance NR RACH procedure to accommodate non-terrestrial networks (NTN) are disclosed. The length of the RAR window may be extended. A NTN-RNTI associated with the time-frequency resources used for the PRACH preamble may be used to scramble the CRC of DCI used for downlink assignment in the RAR. The DCI content may include information on the associated PRACH preamble to assist the UE in distinguishing between RARs generated as a response to PRACH preambles transmitted by different UEs from different system frames. The NTN-RNTI may contain information on the system frames when the UE sends the PRACH preamble. The RA-RNTI associated with the time-frequency resources used for the PRACH preambles transmitted from different frames may be used to scramble different subsets of the CRC of the DCI format 1_0 to assist the UE in distinguishing between RARs generated in response to the different PRACH preambles.

Claims22

Dependent claims

A method of accessing a communication network by a wireless user equipment (UE), the method comprising:

transmitting, by the UE to a base station of the communication network, a physical random access channel (PRACH) preamble during a frame of a frame structure that includes a plurality of frames to request access to the communication network, wherein time-frequency resources of the frame used for transmitting the PRACH preamble is uniquely associated with a radio network temporary identifier (RNTI) of the UE;
determining, by the UE during a random access response (RAR) window that spans a plurality of the frames, whether a RAR message received from the base station is intended for the UE based on the RNTI and a frame number of the frame used for transmitting the PRACH preamble;
and
contending by the UE for resources of the communication network in response to determining that the RAR message is intended for the UE.

1 more element

Dependencies are inferred from the claim text.

Rach procedures for non-terrestrial networks for user equipment

Life of this patent

Rach procedures for non-terrestrial networks for user equipment

Life of this patent

Abstract

Claims22