Decision-feedback equalization for CDMA downlink
نویسندگان
چکیده
A well–known receiver strategy for a linearly modulated signal transmitted over a frequency–selective channel is channel equalization. Recently it was proposed to employ a minimum mean–squared error (MMSE) channel equalizer for the downlink of CDMA. In this paper, we introduce a new receiver concept using MMSE channel equalization as a first stage and MMSE decision–feedback equalization (DFE) utilizing soft feedback from the decoding unit as a second stage. Both schemes are compared for the downlink of CDMA. It turns out, that after channel decoding we gain about 1 dB compared to conventional MMSE channel equalization.
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