Device and method for performing random access in non-terrestrial network system

A method for performing wireless communication by a network node in a non-terrestrial network (NTN), the method comprising:

• determining a propagation delay parameter or a satellite altitude parameter associated with a serving cell;
• selecting a cyclic shift value from among a plurality of cyclic shift values based on the propagation delay parameter or the satellite altitude parameter;
• transmitting, to a user equipment (UE), random access channel (RACH) configuration information indicating the selected cyclic shift value;
• receiving a random access preamble from the UE;
• and
• transmitting a response message to the UE.

A user equipment (UE) comprising:

• a transceiver;
• and
• a processor configured to:
• receive random access channel (RACH) configuration information including zero correlation zone (ZCZ) configuration information;
• obtain a propagation delay parameter or a satellite altitude parameter associated with a serving cell of a non-terrestrial network (NTN);
• select a cyclic shift value based on the propagation delay parameter or the satellite altitude parameter;
• generate a random access preamble based on the selected cyclic shift value;
• and
• control the transceiver to transmit the random access preamble.

A non-transitory computer-readable medium storing instructions that, when executed by a processor of a user equipment (UE), cause the UE to perform the method comprising:

• receiving, from a network node, random access channel (RACH) configuration information including zero correlation zone (ZCZ) configuration information;
• obtaining a propagation delay parameter associated with a serving cell of a non-terrestrial network (NTN);
• selecting a cyclic shift value from among a plurality of cyclic shift values based on the propagation delay parameter;
• generating a random access preamble based on the selected cyclic shift value;
• and
• transmitting the random access preamble to the network node,
• wherein the plurality of cyclic shift values includes:
• a first cyclic shift set corresponding to a first coverage range, and
• a second cyclic shift set corresponding to a second coverage range larger than the first coverage range.