Patent ID: 7778150

Claim:
A radio apparatus for transmitting, in a predetermined period of time, a plurality of packet signals each of which is formed by streams transmitted from a plurality of antennas in parallel, the apparatus comprising: an adjustment unit which adjusts the number of streams for the plurality of packet signals, respectively; a specifying unit which specifies a packet signal whose number of streams is maximum among the packet signals whose numbers of streams have been adjusted by said adjustment unit; a generation unit which includes a first means that assigns known signals and data signals to the streams, respectively, for the packet signal specified by said specifying unit and assigns extensional known signals to another stream to which no data signals are assigned by setting the another stream to which no data signals are assigned, and a second means that assigns a known signal and a data signal to at least one stream for a packet signal not specified by said specifying unit; and a transmitter which transmits a plurality of packet signals generated by said generation unit.