Pilot-signal aided multiuser timing estimation in DS-CDMA communications

Most works on multiuser synchronization do not utilise pilot signals to facilitate their designs. Although these approaches are suitable for general cases, pilot-signal aided schemes potentially outperform these generalized designs over either complexity reduction or performance enhancement. In this paper, utilizing specially designed training sequences, optimum multiuser timing estimators with linear-complexity are introduced for practical applications. In addition, a suboptimum timing estimator based on binary-valued training sequences is also proposed. These pilot-signal aided approaches are mathematically and numerically confirmed to be effective for practical applications