Title :
Decision-feedback equalization for CDMA downlink
Author :
Rössler, Jürgen E. ; Lampe, Lutz H J ; Gerstacker, Wolfgang H. ; Huber, Johannes B.
Author_Institution :
Erlangen-Nurnberg Univ., Erlangen, Germany
fDate :
6/24/1905 12:00:00 AM
Abstract :
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.
Keywords :
code division multiple access; decision feedback equalisers; decoding; least mean squares methods; mobile radio; radio receivers; time-varying channels; CDMA downlink; DFE; MMSE channel equalizer; UMTS; Universal Mobile Telecommunications System; decision-feedback equalization; decoding unit; frequency-selective channel; linearly modulated signal transmission; minimum mean.-squared error; receiver strategy; soft feedback; third-generation mobile radio; wideband code-division multiple access; 3G mobile communication; Decision feedback equalizers; Delay estimation; Downlink; Finite impulse response filter; Gain; Intersymbol interference; Maximum likelihood decoding; Maximum likelihood estimation; Multiaccess communication;
Conference_Titel :
Vehicular Technology Conference, 2002. VTC Spring 2002. IEEE 55th
Print_ISBN :
0-7803-7484-3
DOI :
10.1109/VTC.2002.1002601
