A base station apparatus comprising: a frame forming section adapted to form a frame that includes a first OFDM symbol and a second OFDM symbol; and a transmitting section adapted to transmit the formed frame; wherein: the second OFDM symbol differs from the first OFDM symbol; a third signal is generated using a pilot signal (PILOT STARTING) and a scrambling code (C1-C48) assigned to the base station apparatus so that the third signal is indicative of the scrambling code; first and second code group sequences (CG1- CG16) are selected based on the scrambling code and based on an association between a plurality of scrambling code candidates (C1-C48) and combinations of the first and second code group sequences, a combination of the first and second code group sequences, being associated with a subset of the plurality of scrambling code candidates that includes the scrambling code, and the first OFDM symbol includes a first signal generated by multiplying the pilot signal with the first code group sequence and a second signal generated by multiplying the pilot signal with the second code group sequence, the first signal being transmitted in first subcarriers included in a first subcarrier group, the second signal being transmitted in second subcarriers included in a second subcarrier group, and the first and second subcarriers differ from each other; the second OFDM symbol includes the third signal. a frame forming section adapted to form a frame that includes a first OFDM symbol and a second OFDM symbol; and a transmitting section adapted to transmit the formed frame; wherein: the second OFDM symbol differs from the first OFDM symbol; a third signal is generated using a pilot signal (PILOT STARTING) and a scrambling code (C1-C48) assigned to the base station apparatus so that the third signal is indicative of the scrambling code; first and second code group sequences (CG1- CG16) are selected based on the scrambling code and based on an association between a plurality of scrambling code candidates (C1-C48) and combinations of the first and second code group sequences, a combination of the first and second code group sequences, being associated with a subset of the plurality of scrambling code candidates that includes the scrambling code, and the first OFDM symbol includes a first signal generated by multiplying the pilot signal with the first code group sequence and a second signal generated by multiplying the pilot signal with the second code group sequence, the first signal being transmitted in first subcarriers included in a first subcarrier group, the second signal being transmitted in second subcarriers included in a second subcarrier group, and the first and second subcarriers differ from each other; the second OFDM symbol includes the third signal. the second OFDM symbol differs from the first OFDM symbol; a third signal is generated using a pilot signal (PILOT STARTING) and a scrambling code (C1-C48) assigned to the base station apparatus so that the third signal is indicative of the scrambling code; first and second code group sequences (CG1- CG16) are selected based on the scrambling code and based on an association between a plurality of scrambling code candidates (C1-C48) and combinations of the first and second code group sequences, a combination of the first and second code group sequences, being associated with a subset of the plurality of scrambling code candidates that includes the scrambling code, and the first OFDM symbol includes a first signal generated by multiplying the pilot signal with the first code group sequence and a second signal generated by multiplying the pilot signal with the second code group sequence, the first signal being transmitted in first subcarriers included in a first subcarrier group, the second signal being transmitted in second subcarriers included in a second subcarrier group, and the first and second subcarriers differ from each other; the second OFDM symbol includes the third signal.