Patent ID: 8873497

Claim:
A method of transmitting power headroom information in a multi-component carrier system using a user equipment, the method comprising: configuring a plurality of component carriers combined from a candidate component carrier group based on component carrier configuration information; triggering a power headroom report on the plurality of combined component carriers; calculating power headroom for the plurality of combined component carriers; and transmitting, to a eNodeB, combination power headroom information including a value of the calculated power headroom; determining whether the user equipment reduces uplink transmission power when maximum uplink transmission power of the user equipment is exceeded owing to dynamic scheduling according to the eNodeB; increasing a scaling count by 1 when the uplink transmission power is reduced; and determining whether the scaling count is equal to a predefined maximum scaling count, wherein the power headroom report on the plurality of combined component carriers is triggered when the power headroom for the plurality of combined component carriers is greater than or equal to a predefined threshold, and wherein the power headroom report on the plurality of combined component carriers is triggered when the scaling count is equal to the predefined maximum scaling count.