Method and apparatus for determining uplink transmission timing for srs transmission in one or more cells in mobile wireless communication system

A terminal comprising:

• a transceiver,
• a memory, and
• a controller coupled to the transceiver and the memory, wherein the controller is configured to cause the terminal to:
• receive in a first cell a specific radio resource control (RRC) message, wherein the specific RRC message comprises an information element (IE) for positioning sounding reference signal (SRS) in RRC inactive state;
• perform state transition to RRC inactive state;
• perform cell reselection to a second cell;
• update, in case that the second cell belongs to a positioning SRS area, by the terminal:
• a stored reference signal received power (RSRP) of downlink pathloss reference based on a RSRP of downlink pathloss reference of the second cell;
• and
• a first timing advance based on a downlink timing difference, and
• perform a positioning SRS transmission in the second cell based on:
• the first timing advance;
• and
• a positioning SRS configuration,
• wherein the IE for positioning SRS in RRC inactive state comprises:
• a field for the positioning SRS area;
• and
• a field for the positioning SRS configuration, and
• wherein the field for positioning SRS area indicates one or more cells where the positioning SRS configuration is valid.