Wireless communication apparatus, wireless communication system, and transmission method

1. A wireless communication apparatus comprising:

a generator to generate a symbol;

an assigner to assign, to the symbol, a given number of units each formed of a time domain symbol and a frequency domain subcarrier in a frame which is formed of M (M is a positive integer) time domain symbols and N (N is a positive integer) frequency domain subcarriers and includes M×N units, and the given number of units including P (P is a positive integer not more than M) time domain symbols and Q (Q is a positive integer not more than N) frequency domain subcarriers; and

a code multiplier to multiply the symbol assigned to the given number of units by respective elements included in a code sequence, elements in the code sequence multiplied by the symbol in each time domain symbol being different from each other, wherein the code multiplier multiplies the symbol by the respective elements, while cyclically shifting the code sequence for a time domain symbol.

2. The apparatus according to claim 1 , wherein the code multiplier multiplies the symbol assigned to the given number of units by the code sequence including M×Q elements corresponding to M time domain symbols and Q frequency domain subcarriers in the frame.

3. The apparatus according to claim 1 , wherein the code multiplier multiplies the symbol assigned to the given number of units by the code sequence including P×N elements corresponding to P time domain symbols and N frequency domain subcarriers in the frame.

4. The apparatus according to claim 1 , wherein the Q frequency domain subcarriers are continuous frequency domain subcarriers.

5. A wireless communication terminal for communicating with a base station, comprising:

a generator to generate a symbol;

a code multiplier to multiply, in order to generate transmission symbols, the symbol by a code sequence including a plurality of elements, the transmission symbols being generated corresponding to the plurality of respective elements of the code sequence, the code sequence being cyclically shifted by a cyclic shift amount, the cyclic shift amount varying with a time domain, the cyclic shift amount depending on the base station; and

a transmitter to transmit the transmission symbols.

6. A method applied to a wireless communication terminal for communicating with a base station, the method comprising:

generating, at a generator at the wireless communication terminal, a symbol;

multiplying, at a multiplier at the wireless communication terminal, in order to generate transmission symbols, the symbol by a code sequence including a plurality of elements to generate transmission symbols corresponding to the plurality of respective elements of the code sequence, the code sequence being cyclically shifted by a cyclic shift amount, the cyclic shift amount varying with a time domain, the cyclic shift amount depending on the base station; and

transmitting, from a transmitter at the wireless communication terminal, the transmission symbols.

7. A wireless communication terminal for communicating with a base station, comprising:

a generator to generate transmission symbols, the transmission symbols being generated by multiplying a symbol by a code sequence including a plurality of elements to generate the transmission symbols corresponding to the plurality of respective elements of the code sequence, the code sequence being cyclically shifted by a cyclic shift amount, the cyclic shift amount varying with a time domain, the cyclic shift amount depending on the base station; and

a transmitter to transmit the transmission symbols.

8. The terminal according to claim 5 , further comprising an antenna to transmit the transmission symbols.

9. The terminal according to claim 7 , further comprising an antenna to transmit the transmission symbols.

10. A method applied to a wireless communication terminal for communicating with a base station, the method comprising:

generating, at a generator at the wireless communication terminal, transmission symbols, the transmission symbols being generated by sequentially multiplying a symbol by a plurality of elements included in a code sequence, the code sequence being cyclically shifted by a cyclic shift amount, the cyclic shift amount varying with a time domain, the cyclic shift amount depending on the base station; and

transmitting, from a transmitter at the wireless communication terminal, the transmission symbols.

11. A wireless communication terminal for communicating with a base station, comprising:

a generator to generate a symbol;

a code multiplying unit configured to multiply the symbol by a code sequence including a plurality of elements to generate a transmission symbol, the code sequence being cyclically shifted by a given number of elements, the given number of elements varying with a time domain, the given number of elements depending on the base station; and

a transmission unit configured to transmit the transmission symbol mapped on frequency subcarriers in the time domain.

12. The terminal according to claim 11 , further comprising an antenna to transmit the transmission symbol.

13. A method applied to a wireless communication terminal for communicating with a base station, the method comprising:

generating, at a generator at the wireless communication terminal, a symbol;

multiplying, at a multiplier at the wireless communication terminal, the symbol by a code sequence including a plurality of elements to generate a transmission symbol, the code sequence being cyclically shifted by a given number of elements, the given number of elements varying with a time domain, the given number of elements depending on the base station; and

transmitting, from a transmitter at the wireless communication terminal, the transmission symbol mapped on frequency subcarriers in the time domain.