Construction of multiple orthogonal subsets based on permutation sequences

Based on permutation of complementary pair set, a new construction algorithm of sequence set with multiple orthogonal subsets is proposed. In the constructed sequence set, each sequence subset has orthogonal property, that is, the in-phase cross-correlation (IPCC) between any two sequences from the same subset is equal to zero. For the normalized IPCC between different subsets, only a few values are taken, namely {0, +0.5, -0.5} or {0, +0.25, -0.25, +0.5, -0.5}. Compared with traditional orthogonal set, the proposed set including multiple orthogonal subsets may provide more sequences, and a traditional orthogonal set may be considered as one subset of the proposed set. As a result, the proposed set with more sequences will obtain higher data rate when it is used in M-ary orthogonal modulation or M-ary spread spectrum communications.