Adaptive bit/power loading technique for a multicarrier communication system

A bit/power loading method in an adaptive modulation-based multicarrier communication system, comprising:

• computing transmission power in each modulation mode of at least one sub-channel according to channel information received from a terminal;
• selecting at least one combination of sub-channel modulation modes with minimum total transmission power for transmitting a total number of bits;
• and
• simultaneously transmitting the total number of bits according to the selected sub-channel modulation mode combination in which a sum of sub-channel transmission power values is minimized,
• wherein the selecting comprises:
• computing initial values of symbol transmission power according to the number of bits for each sub-channel;
• and
• computing minimum transmission power and the number of bits per symbol sub-channel by sub-channel using the initial values, and
• the minimum transmission power is a sum of minimum symbol transmission power of a current sub-channel and symbol transmission power of a previous sub-channel for a difference between the total number of bits and the number of bits per symbol of the current sub-channel.