Buffer status reporting in a mobile communication system

A method for a base station comprising:

• transmitting, by the base station, a semi-persistent scheduling activation to a mobile terminal via physical downlink control channel signaling;
• receiving, by the base station, a scheduling request from the mobile terminal in order to request uplink resources for uplink transmission including transmission of a buffer status report when semi-persistent scheduling is not activated, wherein when semi-persistent scheduling is activated, the mobile terminal checks a setup information element of a respective logical channel to determine whether to trigger a scheduling request or not;
• when the mobile terminal determines to trigger the scheduling request, receiving, by the base station, the scheduling request transmitted from the mobile terminal for the logical channel;
• and
• when the mobile terminal determines not to trigger the scheduling request, not receiving, by the base station, the scheduling request from the mobile terminal;
• wherein the physical downlink control channel signaling is transmitted by the base station to the mobile terminal for activation of a scheduling mode, including a dynamic scheduling mode in which radio resources are dynamically allocated by dynamic grants and a semi-persistent scheduling mode in which radio resources are allocated on a semi-persistent basis by semi-persistent scheduling grants.