US 11,706,794 B2 · Physical random access for NR-U

Abstract

Systems, methods, and instrumentalities are disclosed herein associated with physical random access, e.g., for new radio (NR) implementations such as NR-unlicensed (NR-U). A wireless transmit/receive unit (WTRU) may switch a position of a PRACH occasion (RO) with another RO to reduce latency (e.g., so that a WTRU can transmit a preamble without performing a LBT operation). Systems, methods, and instrumentalities are disclosed for reserving a listen-before-talk (LBT) procedure gap at the beginning of a random access channel (RACH) occasion (RO) in New Radio (NR) unlicensed (NR-U) systems. The present systems, methods, and instrumentalities may (e.g., may also) be applied to consecutive ROs. This may include reserving a LBT gap for example, for a RO transmission (e.g., for each of the consecutive ROs). Low latency RACH for NR-U systems may be supported (e.g., mapping rules for the RO may be implemented).

Claims21

Dependent claims

A wireless transmit/receive unit (WTRU), comprising:

a processor configured at least in part to:
determine, based on first configuration information, a first order associated with a plurality of synchronization signal (SS)/physical broadcast channel (PBCH) blocks (SSBs) and a plurality of PRACH occasions (ROs),
wherein, in the determined first order, a first RO is next in time after a first SSB;
determine, based on the first configuration information, that the first RO is associated with one of:
the first SSB or an SSB other than the first SSB;
and
send a preamble,
wherein:
if the first RO is determined to be associated with the first SSB, send, according to the determined first order, the preamble in the first RO after reception of the first SSB, and
if the first RO is determined to be associated with the SSB other than the first SSB:
determine, based on second configuration information, a second order associated with the plurality of SSBs and the plurality of ROs,
wherein, in the determined second order, a second RO is next in time after the first SSB, and send, according to the determined second order, the preamble in the second RO after the reception of the first SSB.

9 more elements

A method implemented in a wireless transmit/receive unit (WTRU), comprising:

determining, based on first configuration information, a first order associated with a first plurality of synchronization signal (SS)/physical broadcast channel (PBCH) blocks (SSBs) and a first plurality of PRACH occasions (ROs),
wherein, a first RO in the determined first order is next in time after a first SSB in the determined first order;
determining, based on the first configuration information, that the first RO in the determined first order is associated with an SSB other than the first SSB in the determined first order;
determining, based on the first RO in the determined first order being associated with the SSB other than the first SSB in the determined first order, a second order associated with the first plurality of SSBs and the first plurality of ROs,
wherein, a second RO in the determined second order is next in time after the first SSB in the determined second order;
and
send, according to the determined second order, a preamble in the second RO after the reception of the first SSB.

4 more elements

Dependencies are inferred from the claim text.

Physical random access for NR-U

Life of this patent

Physical random access for NR-U

Life of this patent

Abstract

Claims21