A user equipment includes circuitry which selects a random access preamble sequence, and a transmitter which transmits the random access preamble sequence to a base station in a frequency bandwidth of an unlicensed band, and performs at least one of a first operation and a second operation. In the first operation, the circuitry selects a first sequence as the random access preamble sequence, the first sequence having a length longer than a length of a random preamble sequence used for a licensed band, and the transmitter transmits the first sequence in the frequency bandwidth of the unlicensed band. In the second operation, the circuitry selects a second sequence as the random access preamble sequence, the second sequence having a length equal to the length of a random preamble sequence used for the licensed band, and the transmitter transmits the second sequence with repetitions in the frequency bandwidth of the unlicensed band.