Communication method, and transmitting apparatus and receiving apparatus using that communication method

1. A transmission method for transmitting an orthogonal frequency division multiplexing signal, the method comprising:

composing, a plurality of carrier groups each including one or more subcarriers;

assigning transmission data for a plurality of transmission destination terminals, to the plurality of carrier groups, at least one carrier group for one transmission destination terminal;

selecting, for each of the carrier groups, one of a first frame configuration where the transmission data is transmitted using one modulated signal, and a second frame configuration where the transmission data is transmitted using a plurality of modulated signals; and

transmitting the assigned transmission data for the plurality of transmission destination terminals at a same time on a time period axis.

2. The transmission method according to claim 1 , wherein the transmitting transmits the one modulated signal from at least one antenna and transmits the plurality of modulated signals from a plurality of antennas.

3. The transmission method according to claim 1 , wherein the transmission data is assigned based on channel state information from the transmission destination terminals.

4. The transmission method according to claim 1 , the transmitting comprising:

transmitting, at a first unit of time, a modulated signal for a first terminal on a first carrier group and a modulated signal for a second terminal on a second carrier group; and

transmitting, at a second unit of time, a modulated signal for a third terminal on the first carrier group and a modulated signal for a fourth terminal on the second carrier group.

5. The transmission method according to claim 4 , wherein the third and fourth terminals are selected from the first and second terminals.

6. A transmitting apparatus comprising:

an orthogonal frequency division multiplexing signal generator that generates an orthogonal frequency division multiplexing signal; and

a frame configuration determiner that composes a plurality of carrier groups, each including one or more subcarriers, and assigns transmission data for a plurality of transmission destination terminals, to the plurality of composed carrier groups, at least one carrier group for one transmission destination terminal; and

a plurality of antennas,

wherein the frame configuration determiner selects, for each of the carrier groups, one of a first frame configuration where one modulated signal is transmitted from at least one antenna, and a second frame configuration where a plurality of modulated signals are transmitted from the plurality of antennas.

7. The transmitting apparatus according to claim 6 , wherein the one modulated signal is transmitted from at least one antenna and the plurality of modulated signals are transmitted from the plurality of antennas.

8. The transmitting apparatus according to claim 6 , wherein the frame configuration determiner composes a frame based on channel state information from the destination terminals.

9. The transmitting apparatus according to claim 6 ,

wherein, at a first unit of time, the frame configuration determine assigns a modulated signal for a first terminal to a first carrier group and assigns a modulated signal for a second terminal to a second carrier group, and at a second unit of time, assigns a modulated signal for a third terminal to the first carrier group and assigns a modulated signal for a fourth terminal to the second carrier group.

10. The transmitting apparatus according to claim 9 , wherein the third and fourth terminals are selected from the first and second terminals.

11. The transmitting apparatus according to claim 6 , wherein each of the plurality of modulated signals are transmitted from a different antenna.