A radio communication method comprising: transmitting a control information to a mobile station using one or plurality of Control Channel Element(s), CCE(s); receiving from the mobile station an acknowledgement or non-acknowledgement, ACK/NACK, signal that is spread with an orthogonal Walsh sequence, selecting the orthogonal Walsh sequence, which corresponds to a Physical Uplink Control Channel, PUCCH, number calculated with a first CCE number of the one or plurality of CCE(s), from a plurality of orthogonal Walsh sequences, the plurality of orthogonal Walsh sequences including more orthogonal Walsh sequences that have two elements with values respectively corresponding to 2nd symbol and 6th symbol of an ACK/NACK signal transmission slot in phase than orthogonal Walsh sequence(s) that have said two values respectively corresponding to the 2nd symbol and the 6th symbol of the ACK/NACK signal transmission slot in opposite phases from each other; despreading, with said selected orthogonal Walsh sequence, the spread ACK/NACK signal in the ACK/NACK signal transmission slot; receiving, from the mobile station, two first reference signals, which are produced by multiplying two reference signal sequences with values having opposite phases from each other and which are arranged in the 2nd symbol and the 6th symbol of a CQI signals transmission slot, and receiving channel quality indicator, CQI, signals arranged in symbols of the CQI signals transmission slot other than the 2nd symbol and the 6th symbol; and demodulating the CQI signals arranged in the CQI signals transmission slot using the received two first reference signals. transmitting a control information to a mobile station using one or plurality of Control Channel Element(s), CCE(s); receiving from the mobile station an acknowledgement or non-acknowledgement, ACK/NACK, signal that is spread with an orthogonal Walsh sequence, selecting the orthogonal Walsh sequence, which corresponds to a Physical Uplink Control Channel, PUCCH, number calculated with a first CCE number of the one or plurality of CCE(s), from a plurality of orthogonal Walsh sequences, the plurality of orthogonal Walsh sequences including more orthogonal Walsh sequences that have two elements with values respectively corresponding to 2nd symbol and 6th symbol of an ACK/NACK signal transmission slot in phase than orthogonal Walsh sequence(s) that have said two values respectively corresponding to the 2nd symbol and the 6th symbol of the ACK/NACK signal transmission slot in opposite phases from each other; despreading, with said selected orthogonal Walsh sequence, the spread ACK/NACK signal in the ACK/NACK signal transmission slot; receiving, from the mobile station, two first reference signals, which are produced by multiplying two reference signal sequences with values having opposite phases from each other and which are arranged in the 2nd symbol and the 6th symbol of a CQI signals transmission slot, and receiving channel quality indicator, CQI, signals arranged in symbols of the CQI signals transmission slot other than the 2nd symbol and the 6th symbol; and demodulating the CQI signals arranged in the CQI signals transmission slot using the received two first reference signals.