A radio apparatus communicates with a plurality of terminal apparatuses by using a packet signal composed of at least one stream. A control unit divides a certain period into a plurality of partial periods and assigns respectively the plurality of partial periods to the plurality of terminal apparatuses by associating the periods with the terminal apparatuses. The control unit also generates a packet signal for use in control and packet signals for use in inquiry. In so doing, the control unit generates the inquiry packet signals for the plurality of respective terminal apparatuses, as a single packet signal. A baseband processing unit and other units transmit the control packet signal and then transmit the inquiry packet signals, and receive packet signals, containing inquiry results, from the plurality of respective terminal apparatuses.