Patent ID: 7899413

Claim:
A radio apparatus comprising: a generation unit configured for generating a packet signal that comprises (1) first known signals assigned to N of M streams (N<M), respectively, (2) second known signals assigned to M streams, respectively, and (3) data assigned to the N of M streams, respectively, the N of M streams each including the first known signal, the second known signal, and the data in that order, applying cyclic timing shifts to the respective second known signals assigned to the N of M streams by timing shift amounts different from each other, the timing shift amounts being given priority and applied to the second known signals assigned to the respective N of M streams in order of the priority, and applying the cyclic timing shifts to the respective second known signals assigned to the streams other than the N of M streams by the timing shift amounts in order of the priority; and a transmitter configured for transmitting the packet signal generated by the generation unit, output timing of the second known signals assigned to the streams other than the N of M streams being different from that of the second known signals assigned to the N of M streams.