Resource selection for random access

An apparatus for wireless communication at a user equipment (UE), comprising:

• one or more processors,
• one or more memories coupled with the one or more processors;
• and
• instructions stored in the one or more memories and executable by the one or more processors to cause the apparatus to:
• determine to perform a random access procedure with a base station;
• receive a plurality of synchronization signal blocks of a set of synchronization signal blocks, wherein each random access occasion of a set of random access occasions corresponds to at least one synchronization signal block of the set of synchronization signal blocks;
• determine, for at least one synchronization signal block of the plurality of synchronization signal blocks, a received power and a value of one or more additional parameters for random access occasion selection, wherein the one or more additional parameters comprise a congestion parameter for a first synchronization signal block of the plurality of synchronization signal blocks;
• determine a value of the congestion parameter based at least in part on a backoff indication from the base station, a quantity of contention resolution failures, a quantity of medium access control subheaders in a random access response, or any combination thereof;
• and
• transmit, to the base station, a first message of the random access procedure in a random access occasion selected from the set of random access occasions, wherein the random access occasion is selected based at least in part on the received power and the value of the congestion parameter.

An apparatus for wireless communication at a user equipment (UE), comprising:

• means for determining to perform a random access procedure with a base station;
• means for receiving a plurality of synchronization signal blocks of a set of synchronization signal blocks, wherein each random access occasion of a set of random access occasions corresponds to at least one synchronization signal block of the set of synchronization signal blocks;
• means for determining, for at least one synchronization signal block of the plurality of synchronization signal blocks, a received power and a value of one or more additional parameters for random access occasion selection, wherein the one or more additional parameters comprise a congestion parameter for a first synchronization signal block of the plurality of synchronization signal blocks;
• means for determining a value of the congestion parameter based at least in part on a backoff indication from the base station, a quantity of contention resolution failures, a quantity of medium access control subheaders in a random access response, or any combination thereof;
• and
• means for transmitting, to the base station, a first message of the random access procedure in a random access occasion from the set of random access occasions, wherein the random access occasion is selected based at least in part on the received power and the value of the congestion parameter, wherein the first message comprises a message 1 of a four-step random access procedure or a message A of a two-step random access procedure.

A non-transitory computer-readable medium storing code for wireless communication at a user equipment (UE), the code comprising instructions executable by one or more processors to:

• determine to perform a random access procedure with a base station;
• receive a plurality of synchronization signal blocks of a set of synchronization signal blocks, wherein each random access occasion of a set of random access occasions corresponds to at least one synchronization signal block of the set of synchronization signal blocks;
• determine, for at least one synchronization signal block of the plurality of synchronization signal blocks, a received power and a value of one or more additional parameters for random access occasion selection, wherein the one or more additional parameters comprise a congestion parameter for a first synchronization signal block of the plurality of synchronization signal blocks;
• determine a value of the congestion parameter based at least in part on a backoff indication from the base station, a quantity of contention resolution failures, a quantity of medium access control subheaders in a random access response, or any combination thereof;
• and
• transmit, to the base station, a first message of the random access procedure in a random access occasion from the set of random access occasions, wherein the random access occasion is selected based at least in part on the received power and the value of the congestion parameter, wherein the first message comprises a message 1 of a four-step random access procedure or a message A of a two-step random access procedure.