Optimal sequences and total weighted square correlation of synchronous CDMA systems

We characterize total weighted square correlation (TWSC) for a given signature set used in synchronous code division multiple access (S-CDMA) systems. A new theorem for TWSC and a new algorithm for obtaining real sequences that meet Welch inequality with equality are presented. Using this algorithm optimal sequences, which achieve sum capacity for overload S-CDMA systems are obtained. Numerical examples for unitary power constraint case and for arbitrary (unequal) power sets are given.

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