Wireless communications terminal, base station device, and resource allocation method

An integrated circuit of a user equipment which, in operation, controls a process of the user equipment, the process comprising:

• receiving a control signal including an ACK/NACK indicator via an enhanced physical downlink control channel (E-PDCCH), wherein the ACK/NACK indicator indicates one of four possible values including a first value and a second value;
• determining, based on the ACK/NACK indicator and an enhanced control channel element (eCCE) number of the received E-PDCCH, a resource number to transmit an ACK/NACK signal for downlink data using a dynamic ACK/NACK resource dynamically allocated in accordance with the control signal,
• wherein the first value indicates a first resource number and the second value indicates a second resource number, and when the first resource number and the second resource number are consecutive numbers, the first resource number and the second resource number indicate physically adjacent resources;
• and
• transmitting the ACK/NACK signal using the dynamic ACK/NACK resource having the determined resource number when the ACK/NACK indicator indicates the first value or the second value.