Provided is a radio communication device which can prevent generation of mutual correlation peak between ZC sequences and reduce degradation of BLER characteristic of a CS-ZC sequence. In this device, a sequence length adjustment unit (103) truncates or extends the ZC sequence while maintaining the symmetry of the ZC sequence inputted from a ZC sequence generation unit (102) so as to adjust the sequence length to the number of subcarriers equivalent to the transmission bandwidth of a reference signal inputted from a sequence length setting unit (101). More specifically, the sequence length adjustment unit (103) truncates or extends any one of symbols constituting the ZC sequence so as to truncate or extend the ZC sequence. A transmission RF unit (107) transmits the ZC sequence after the sequence length adjustment.