UE-Selection of a Contention-Based Random Access Procedure

A method, performed by a user equipment (UE), for selecting a contention-based random-access (CBRA) procedure for an initial access to a cell served by a network node in a wireless communication network, the method comprising:

• determining a value indicative of a current timing advance (TA);
• when the value does not exceed a certain threshold, selecting a first CBRA procedure that does not include receiving a TA command prior to transmitting payload data to the cell;
• otherwise selecting a second CBRA procedure that includes receiving a TA command prior to transmitting payload data to the cell;
• and
• performing the selected CBRA procedure for the initial access to the cell, comprising:
• when the first CBRA procedure is selected, transmitting the payload data by using the determined TA value;
• and
• when the second CBRA procedure is selected, transmitting the payload data by using a TA value derived from the TA command.

A user equipment (UE), comprising:

• a radio transceiver configured for communicating with a network node in the wireless communication network;
• and
• processing circuitry operatively coupled to the radio transceiver, whereby the processing circuitry and the radio transceiver are configured to:
• determine a value indicative of a current timing advance (TA);
• when the value does not exceed a certain threshold, select a first contention-based random-access (CBRA) procedure that does not include receiving a TA command prior to transmitting payload data to the cell;
• otherwise select a second CBRA procedure that includes receiving a TA command prior to transmitting payload data to the cell;
• and
• perform the selected CBRA procedure for the initial access to the cell, comprising:
• when the first CBRA procedure is selected, transmit the payload data by using the determined TA value;
• and
• when the second CBRA procedure is selected, transmit the payload data by using a TA value derived from the TA command.