SIC/LMMSE detector for 3GPP WCDMA enhanced uplink system over multipath fading channels
Résumé
This paper deals with multiuser detection for the WCDMA enhanced uplink system with low spreading factors over multipath channels. The performance of the conventional detector is significantly degraded by multiple access interference (MAI) and inter-path interference (IPI) effects. However, these problems can be resolved by the interworking of multiuser detector with linear minimum mean squared error (LMMSE) filter. In this paper, we propose a new multiuser detector structure which is the combination of the successive interference canceller (SIC) with LMMSE chip-level equalizer. The matched filter of the standard SIC is replaced
by the LMMSE receiver, in order to decrease the IPI effect. We will show that the new SIC/LMMSE detector improves the block error rate of the data physical channels performance (BLER edch ). This enhancement achieves, for the modulation and coding scheme 1 (MCS1), almost 4dB at a BLER edch equal to 10−2.