Patent ID: 8351469

Claim:
A radio communication method in a radio communication system in which each of user terminals together with transmitting a data signal to a base station using different data transmission band frequencies that are assigned by the base station, performs time-division multiplexing of a pilot signal with the data signal and transmits the resulting signal to the base station, comprising: deciding a pilot transmission band for each user terminal so that the pilot transmission band covers the data transmission band of the user terminal by frequency offset; and instructing each user terminal to transmit the pilot signal using the frequencies of said decided pilot transmission band wherein a CAZAC sequence is used as said pilot signal, wherein said instructing comprises: calculating an amount of said frequency offset for each user terminal, and an amount of cyclic shift of the CAZAC sequence corresponding to the number of user terminals multiplexed by cyclic shifting and the amount of the frequency offset; and instructing each user terminal to perform cyclic shift of said CAZAC sequence used as the pilot signal by the cyclic shift amount, and perform frequency offset of the pilot transmission band by said frequency offset amount.