US 12,452,807 B2
Efficient PRACH transmission in a fallback RACH procedure
Pranav Tripathi, San Jose, CA (US); Dhiraj J. Shirke, San Jose, CA (US); Imran Haider G. Balsania, San Jose, CA (US); and Sanjeevi Balasubramanian, San Jose, CA (US)
Assigned to Apple Inc., Cupertino, CA (US)
Filed by Apple Inc., Cupertino, CA (US)
Filed on Aug. 29, 2022, as Appl. No. 17/822,952.
Claims priority of provisional application 63/261,596, filed on Sep. 24, 2021.
Prior Publication US 2023/0099913 A1, Mar. 30, 2023
Int. Cl. H04W 74/0833 (2024.01); H04W 56/00 (2009.01); H04W 74/00 (2009.01); H04W 52/36 (2009.01)
CPC H04W 74/0833 (2013.01) [H04W 56/001 (2013.01); H04W 74/004 (2013.01); H04W 52/367 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A processor of a user equipment (UE) configured to perform operations comprising:
initiating a two-step random access channel (RACH) procedure to synchronize with a base station;
deriving a first physical random access channel (PRACH) transmit power parameter value for a transmission to be made during the two-step RACH procedure based on at least a physical uplink shared channel (PUSCH) payload transmit power parameter and a total transmit power parameter;
initiating a fallback four-step RACH procedure after the two-step RACH procedure;
configuring a random access preamble transmission for the four-step RACH procedure, wherein configuring the random access preamble transmission comprises deriving a second PRACH transmit power parameter value for a transmission to be made during the four-step RACH procedure based on at least the first PRACH transmit power parameter value; and
transmitting the random access preamble for the four-step RACH procedure to the base station.