US Patent No. 10,893,544

BEAM REFINEMENT IN TWO-STEP RANDOM ACCESS CHANNEL (RACH) PROCEDURE


Patent No. 10,893,544
Issue Date January 12, 2021
Title Beam Refinement In Two-step Random Access Channel (rach) Procedure
Inventorship Sami-Jukka Hakola, Kempele (FI)
Emad Farag, Flanders, NJ (US)
Timo Koskela, Oulu (FI)
Mihai Enescu, Espoo (FI)
Assignee Nokia Technologies Oy, Espoo (FI)

Claim of US Patent No. 10,893,544

1. A method of communications, comprising:receiving, by a user equipment (UE), a plurality of synchronization signal blocks (SSBs), a plurality of channel state information-reference signals (CSI-RSs) associated with each of the plurality of synchronization signal blocks (SSBs), and random access channel (RACH) configuration data from a gNB, the random access channel (RACH) configuration data associated with a two-step random access channel (RACH) procedure; and
transmitting, by the user equipment (UE), a first message of the two-step random access channel (RACH) procedure to the gNB, the first message including a first portion and a second portion, wherein:
the first portion includes a preamble associated with a selected channel state information-reference signal (CSI-RS) of the plurality of channel state information- reference signals (CSI-RSs), the selected channel state information-reference signal (CSI-RS) further associated with a selected synchronization signal block (SSB) of the plurality of synchronization signal blocks (SSBs), the second portion includes data associated with the preamble, the data transmitted using pre-configured or pre- allocated resources, and
a resource or resource set associated with the selected channel state information- reference signal (CSI-RS) and/or the selected synchronization signal block (SSB) is selected, the first portion transmitted using the selected resource or resource set, and the selected resource or resource set indicating, to the gNB, the selected channel state information-reference signal (CSI-RS) used for determining a transmit beam for transmitting the second portion of the first message.