A New Geometrical Interpretation of the Decorrelator in Multiuser CDMA
نویسندگان
چکیده
|In this paper we present a new geometrical interpretation of the multiuser CDMA decorrelator. This interpretation relates the output of the decorrelator to the subspace spanned by the spreading codes. The interpretation makes it clear that a decision feedback detector based on the soft outputs from a decorrelator and a multistage detector with a soft output rst stage decorre-lator do not provide any performance improvement over the single stage decorrelator. These conclusions are con-rmed by analytical results.
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