Methods for balancing resources utilized in random-access procedures

A method for a network node to facilitate user equipment (UE) random access to a cell in a wireless network, the method comprising:

• detecting a random-access preamble transmitted by a UE on a random access channel (RACH);
• mapping the detected random-access preamble to one of a plurality of available physical uplink shared channel (PUSCH) resource units (PRUs) based on a mapping constraint that comprises:
• one or more of the available PRUs are not used for the mapping, and
• an integer number of the available random-access preambles are mapped to each of the available PRUs that are used for the mapping;
• and
• receiving a data message transmitted by the UE on the PRU to which the detected random-access preamble is mapped.

A user equipment (UE) configured for random access to a cell in a wireless network, the UE comprising:

• radio transceiver circuitry configured to communicate with a network node serving the cell;
• and
• processing circuitry operatively coupled to the radio transceiver circuitry, whereby the processing circuitry and the radio transceiver circuitry are configured to:
• select one of a plurality of available random-access preambles;
• map the selected random-access preamble to one of a plurality of available physical uplink shared channel (PUSCH) resource units (PRUs) based on a mapping constraint that comprises:
• one or more of the available PRUs are not used for the mapping, and
• an integer number of the available random-access preambles are mapped to each of the available PRUs that are used for the mapping;
• transmit the selected random-access preamble on a random access channel (RACH);
• and
• transmit a data message on the PRU to which the selected random-access preamble is mapped.

A network node configured to facilitate user equipment (UE) random access to a cell in a wireless network, the network node comprising:

• radio network interface circuitry configured to communicate with UEs;
• and
• processing circuitry operatively coupled to the radio network interface circuitry, whereby the processing circuitry and the radio network interface circuitry are configured to:
• detect a random-access preamble transmitted by a UE on a random access channel (RACH);
• map the detected random-access preamble to one of a plurality of available physical uplink shared channel (PUSCH) resource units (PRUs) based on a mapping constraint that comprises:
• one or more of the available PRUs are not used for the mapping, and
• an integer number of the available random-access preambles are mapped to each of the available PRUs that are used for the mapping;
• and
• receive a data message transmitted by the UE on the PRU to which the detected random-access preamble is mapped.