17598223. RACH PROCEDURES FOR NON-TERRESTRIAL NETWORKS FOR USER EQUIPMENT simplified abstract (Apple Inc.)

RACH PROCEDURES FOR NON-TERRESTRIAL NETWORKS FOR USER EQUIPMENT

Organization Name

Apple Inc.

Inventor(s)

Chunxuan Ye of Cupertino CA (US)

Dawei Zhang of Cupertino CA (US)

Haitong Sun of Cupertino CA (US)

Sigen Ye of Cupertino CA (US)

Weidong Yang of Cupertino CA (US)

Oghenekome Oteri of Cupertino (US)

Hong He of Cupertino CA (US)

Yushu Zhang of Cupertino CA (US)

Sarma V. Vangala of Cupertino CA (US)

Haijing Hu of Cupertino CA (US)

RACH PROCEDURES FOR NON-TERRESTRIAL NETWORKS FOR USER EQUIPMENT - A simplified explanation of the abstract

This abstract first appeared for US patent application 17598223 titled 'RACH PROCEDURES FOR NON-TERRESTRIAL NETWORKS FOR USER EQUIPMENT

Simplified Explanation

The patent application describes methods and systems to improve the NR RACH procedure for non-terrestrial networks (NTN). Here are the key points:

• The RAR window, which is the time interval for receiving RAR messages, can be extended to accommodate NTN.
• A NTN-RNTI (Radio Network Temporary Identifier) is used to scramble the CRC (Cyclic Redundancy Check) of DCI (Downlink Control Information) used for downlink assignment in the RAR.
• The DCI content includes information about the associated PRACH (Physical Random Access Channel) preamble, helping the UE (User Equipment) distinguish between RARs generated in response to different PRACH preambles from different UEs and system frames.
• The NTN-RNTI contains information about the system frames when the UE sends the PRACH preamble.
• The RA-RNTI (Random Access-RNTI) associated with the time-frequency resources used for PRACH preambles from different frames is used to scramble different subsets of the CRC of the DCI format 1_0, aiding the UE in distinguishing between RARs generated for different PRACH preambles.

Potential applications of this technology:

• Enhancing the RACH procedure for non-terrestrial networks, such as satellite communication systems.
• Improving the efficiency and reliability of communication between user equipment and non-terrestrial networks.
• Enabling seamless integration of non-terrestrial networks into existing cellular communication systems.

Problems solved by this technology:

• Non-terrestrial networks have unique characteristics and requirements that may not be fully supported by existing RACH procedures.
• The patent addresses the challenges of accommodating NTN in the RACH procedure, ensuring efficient and reliable communication.

Benefits of this technology:

• Extended RAR window allows for better reception of RAR messages in NTN scenarios.
• Scrambling the CRC of DCI with NTN-RNTI and RA-RNTI helps the UE distinguish between RARs for different PRACH preambles, improving system performance.
• The inclusion of PRACH preamble information in DCI assists the UE in correctly associating RARs with the corresponding PRACH preambles, reducing errors and improving overall communication reliability.

Original Abstract Submitted

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.