Constructions of optimal and near-optimal quasi-complementary sequence sets from singer difference sets

Compared with the perfect complementary sequence sets, quasi-complementary sequence sets (QCSSs) have the advantage of supporting more users in multicarrier CDMA communications. Constructions for optimal and near-optimal periodic QCSSs are proposed in this paper by using the Singer difference sets and the existing optimal quaternary sequence sets. The maximum periodic correlation magnitude of the proposed optimal QCSS achieves the derived periodic correlation lower bound asymptotically. To the authors' best knowledge, such optimal QCSSs haven't been reported before.