Communication method for transmitting multiple packet signals, and radio apparatus and communication system using the same

A method for communicating with a plurality of terminal apparatuses by using a packet signal composed of at least one stream, the method comprising:

• dividing a specified period into a plurality of partial periods and assigning the corresponding partial periods respectively to the plurality of terminal apparatuses by associating those periods with the terminal apparatuses;
• generating a control packet signal containing information on the corresponding partial periods assigned to the plurality of respective terminal apparatuses and generating a check packet signal in which known signals are assigned to streams, respectively, the number of the streams to which the known signals are assigned being greater than the number of streams to which data signal is assigned;
• and
• transmitting the control packet generated by said generating, then transmitting the check packet signal in a corresponding partial period assigned by said assigning, and then receiving packet signals containing check results from the plurality of respective terminal apparatuses, in the corresponding partial periods assigned by said assigning,
• wherein said generating is such that the check packet signal for the plurality of respective terminal apparatuses is generated as a single packet signal.

A communication system, comprising:

• a plurality of terminal apparatuses;
• and
• a base station apparatus which communicates with the plurality of terminal apparatuses by using a packet signal composed of at least one stream, said base station apparatus comprising:
• an assignment unit which divides a specified period into a plurality of partial periods and assigns corresponding partial periods respectively to the plurality of terminal apparatuses by associating those periods with the terminal apparatuses;
• a generation unit which generates a control packet signal containing information on the corresponding partial periods assigned to the plurality of respective terminal apparatuses by the assigning unit and which generates a check packet signal in which known signals are assigned to streams, respectively, the number of the streams to which the known signals are assigned being greater than the number of streams to which data signal is assigned;
• and
• a communication unit including:
• a transmitting means which transmits the check packet signal in a corresponding partial period assigned by the assignment unit, after the control packet signal generated by said generation unit has been transmitted;
• and
• a receiving means which receives packet signals containing check results from the plurality of respective terminal apparatuses, in the corresponding partial periods assigned by the assignment unit,
• wherein the generation unit generates the check packet signal for the plurality of respective terminal apparatuses, as a single packet signal.

A radio apparatus for communicating with a plurality of terminal apparatuses by using a packet signal composed of at least one stream, the apparatus comprising:

• a transmitter which transmits a control packet signal that contains information on transmit timings and receive timings assigned respectively to the plurality of terminal apparatuses and then transmitting a check packet signal in which known signals are assigned to streams, respectively, the number of the streams to which the known signals are assigned being greater than the number of streams for data signals;
• and
• a receiver which receives packet signals containing check results from the plurality of respective terminal apparatuses,
• wherein said transmitter generates the check packet signal for the plurality of respective terminal apparatuses, as a single packet signal.