Constructions of Optimal and Near-Optimal Quasi-Complementary Sequence Sets from an Almost Difference Set
This work addresses a domain-specific problem in communication systems, offering incremental improvements in sequence design for CDMA applications.
The paper tackled the problem of supporting more users in multicarrier CDMA communications by constructing a near-optimal periodic quasi-complementary sequence set (QCSS) using an optimal quaternary sequence set and an almost difference set, achieving an exponential growth in the number of users supported by subcarrier channels.
Compared with the perfect complementary sequence sets, quasi-complementary sequence sets (QCSSs) can support more users to work in multicarrier CDMA communications. A near-optimal periodic QCSS is constructed in this paper by using an optimal quaternary sequence set and an almost difference set. With the change of the values of parameters in the almost difference set, the near-optimal QCSS can become asymptotically optimal and the number of users supported by the subcarrier channels in CDMA system has an exponential growth.