User equipment, network node and methods therein for handling a two-step random access procedure in a wireless communications network

A method performed by a network node, for handling a two-step Random Access Channel, RACH, procedure in a wireless communications network, the method comprising:

• sending, to a user equipment, UE, a Physical Downlink Control Channel, PDCCH, order and a Radio Resource Control, RRC, signalling comprising a PUSCH resource table;
• sending, to the UE, any one of:
• a PDCCH order and a RRC signalling, the any one of the PDCCH order and the RRC signalling is triggering a Random Access, RA, and the any one of the PDCCH order and the RRC signalling comprises a Physical Random Access Channel, PRACH, preamble index and at least one of an indication pointing to a Physical Uplink Shared Channel, PUSCH, resource, a Modulation and Coding Scheme, MCS, and a power allocated for PUSCH transmissions;
• and
• receiving, from the UE, a transmission comprising both a PRACH preamble and a Msg 3, the PRACH preamble and Msg 3 being received in the same sub frame, the PRACH preamble being selected from a group of preambles corresponding to the RA event, the Msg3 being received on a PUSCH resource indicated by a grant obtained from the PUSCH resource table based on the indication sent to the UE, and, in the table, each PUSCH resource entry in the table being associated with the following characteristics:
• indices for Bandwidth Parts (BWPs);
• and
• a time period that the grant is valid since the PUSCH transmission starts.

A user equipment, UE, for handling a two-step Random Access Channel, RACH, procedure, in a wireless communications network, the UE being configured to:

• obtain a Physical Uplink Shared Channel, PUSCH, resource table comprising a plurality of PUSCH resources, each PUSCH resource out of the plurality of PUSCH resources corresponds to a preamble assigned for the two-step RACH procedure, obtain the PUSCH resource table comprises receiving a Physical Downlink Control Channel, PDCCH, order and a Radio Resource Control, RRC, signaling comprising the PUSCH resource table from the network node;
• when a Random Access, RA, event is triggered:
• obtain a Physical Random Access Channel, PRACH, preamble corresponding to the RA event and a desired grant size, by randomly selecting a preamble adapted to map to an entry of the Physical Uplink Shared Channel, PUSCH, resource table, adapted to provide a required size of a PUSCH resource for the triggered RA event, the preamble being selected from a group of preambles corresponding to the RA event;
• and
• obtain a grant from the PUSCH resource table based on the obtained PRACH preamble, which grant comprises an indication of a PUSCH resource to use for a Msg 3 transmission in Uplink, UL, in the table, each PUSCH resource entry in the table being associated with the following characteristics:
• indices for Bandwidth Parts (BWPs);
• and
• a time period that the grant is valid since the PUSCH transmission starts.

A network node for handling a two-step Random Access Channel, RACH, procedure in a wireless communications network, the network node being configured to:

• send, to a user equipment, UE, a Physical Downlink Control Channel, PDCCH, order and a Radio Resource Control, RRC, signaling comprising a Physical Uplink Shared Channel, PUSCH, resource table;
• send to a UE any one of:
• a PDCCH order and a RRC signalling, any one of the PDCCH order and the RRC signalling is triggering a Random Access, RA, and the any one of the PDCCH order and the RRC signalling comprises a Physical Random Access Channel, PRACH, preamble index and at least one of an indication pointing to a Physical Uplink Shared Channel, PUSCH, resource, a Modulation and Coding Scheme, MCS, and a power allocated for PUSCH transmissions;
• and
• receive from the UE a transmission comprising both a PRACH preamble and a Msg 3, wherein the PRACH preamble and Msg 3 are received in the same or in subsequent sub frames, the PRACH preamble being selected from a group of preambles corresponding to the RA event, the Msg3 being adapted to be received on a PUSCH resource indicated by a grant adapted to be obtained from a PUSCH resource table based on the indication sent to the UE, and, in the table, each PUSCH resource entry in the table being adapted to be associated with the following characteristics:
• indices for Bandwidth Parts (BWPs);
• and
• a time period that the grant is valid since the PUSCH transmission starts.