User separation in DS-CDMA systems with unknown long PN spreading codes

We consider the user separation problem for CDMA transmissions employing unknown long PN spreading codes. Using the analytical framework underlying our recent results for symbol-periodic spreading, but this time capitalizing on the properties of PN sequences, we show that user separation is possible, provided sufficient spreading is available. Once separated, the individual user data streams may be equalized using single-user blind equalization techniques.

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