A transmission apparatus, a transmission method, a wireless communication system and method. Generate a first group of orthogonal cover code sequences C1 represented by a matrix of [Cn, 1(1), Cn, 1(2), . . . Cn, 1(M)], which satisfy that any adjacent truncated sub cover code sequences [C2j−1, 1(2m−1), C2j−1, 1(2m)] and [C2j, 1(2m−1), C2j, 1(2m)] are also mutually orthogonal, wherein n is an index of N orthogonal cover code sequences included in the first group of orthogonal cover code sequences, M is a spreading factor of the orthogonal cover code sequence as a spreading sequence, N≦M, j is an integer satisfying 1≦j≦N/2, and m is an integer satisfying 1≦m≦M/2; perform column mirroring on the first group of orthogonal cover code sequences, so as to generate a second group of orthogonal cover code sequences C2 ; perform cyclic shift processing of column vectors on the first group of orthogonal cover code sequences, so as to generate a third group of orthogonal cover code sequences C3; column mirroring on the third group of orthogonal cover code sequences, so as to generate a fourth group of orthogonal cover code sequences C4; and a transmitter configured to: transmit each of the first group, second group, third group, and fourth group of orthogonal cover code sequences.