Integrated circuit for spreading response signal

A base station apparatus comprising:

• a transmitting unit configured to transmit data to a radio communication device and transmit, to the radio communication device, control information on one or a plurality of control channel elements (CCEs) with consecutive CCE number(s);
• and
• a receiving unit configured to receive from the radio communication device a response signal for the data;
• wherein,
• the response signal is first-spread with a sequence defined by a cyclic shift value, which is determined from a starting CCE number of the one or more CCE(s) on which the control information is transmitted, and is second-spread with an orthogonal sequence, which is determined among a plurality of orthogonal sequences from said starting CCE number;
• in case the control information is transmitted on one CCE, the cyclic shift value is associated with the starting CCE number of said one CCE, the orthogonal sequence is determined from said starting CCE number, and a cyclic shift value consecutive to said cyclic shift value used with the same orthogonal sequence is associated with a starting CCE number of one or more CCE(s);
• and
• in case the control information is transmitted on plural CCEs, the cyclic shift value is associated with the starting CCE number of said plural CCEs, the orthogonal sequence is determined from said starting CCE number, and a cyclic shift value consecutive to said cyclic shift value used with the same orthogonal sequence is associated with a starting CCE number of one CCE.