Radio communication method, radio terminal device, and base station device

1. A radio communication method used in a radio communication system including a radio terminal device and a base station device, the method comprising:

by the radio terminal device,

generating indicating signals that are different between blocks of radio resources each of which is an allocation unit of data and includes a plurality of symbols;

mapping the indicating signals generated and transmission data to the blocks such that one of the indicating signals and the transmission data are mapped to different symbols in one block; and

transmitting a signal including the blocks;

by the base station device,

receiving the signal including the blocks of the radio resources;

evaluating continuity of the blocks, based on the indicating signals mapped to the blocks; and

demodulating data mapped to the blocks for each radio terminal device, based on an evaluation result.

2. The radio communication method according to claim 1 , wherein the generating includes generating the indicating signals by cyclically extending a signal sequence having a sequence length that is equal to or smaller than size of each block from a starting point that is different for each block.

3. The radio communication method according to claim 2 , wherein the generating includes generating, when size of the transmission data corresponds to blocks the number of which is equal to or larger than a predetermined number, the indicating signals by cyclically extending a plurality of different signal sequences.

4. The radio communication method according to claim 2 , wherein the evaluating includes:

generating a replica of an indicating signal for each block, based on the signal sequence; and

detecting correlation between the replica generated and the blocks included in the signal received.

5. The radio communication method according to claim 2 , wherein the generating includes generating, when a plural pieces of transmission data for a plurality of radio terminal devices are code-multiplexed, the indicating signals by cyclically extending a signal sequence from the starting point that is different and corresponds to each of a plurality of codes.

6. The radio communication method according to claim 1 , wherein the generating includes orthogonally coding the indicating signals generated.

7. The radio communication method according to claim 2 , wherein the generating includes setting the starting point that is different for each block, based on the sequence length of the signal sequence, a maximum number of a plural pieces of transmission data multiplexed to the blocks, and presence of orthogonal coding of the indicating signals.

8. A radio terminal device comprising:

a processor configured to execute a process including

generating indicating signals that are different between blocks of radio resources each of which is an allocation unit of data and includes a plurality of symbols, and

mapping the indicating signals generated and transmission data to the blocks such that one of the indicating signals and the transmission data are mapped to different symbols in one block; and

a transmission circuit configured to transmit a signal including the blocks.

9. A base station device comprising:

a reception circuit configured to receive a signal including a plurality of blocks of radio resources each of which is an allocation unit of data and includes a plurality of symbols;

a processor configured to execute a process including

evaluating continuity of the blocks, based on indicating signals mapped to the blocks such that one of the indicating signals and data are mapped to different symbols in one block and having predetermined regularity between consecutive blocks transmitted from a same transmission source, and

demodulating the data mapped to the blocks for each transmission source, based on a result of evaluation at the evaluating.