Variance-reduced partial parallel interference cancellation for MC-CDMA uplink systems

Authors:
Chin-Liang Wang;Chang-Chen Chu;Chih-Chiang Wu
Affiliations:
Department of Electrical Engineering and the Institute of Communications Engineering, National Tsing Hua University, Hsinchu, Taiwan, Republic of China;Institute of Communications Engineering, National Tsing Hua University, Hsinchu, Taiwan, Republic of China;MediaTek Inc., Hsinchu, Taiwan, Republic of China
Venue:
IEEE Transactions on Wireless Communications
Year:
2009

Citing 3
Cited 1

Multiuser Detection

Multiuser Detection
OFDM for Wireless Multimedia Communications

OFDM for Wireless Multimedia Communications
Multi-user detection for DS-CDMA communications

IEEE Communications Magazine

Adaptive parallel interference cancellation for CDMA systems-A weight selection and filtering scheme

Signal Processing

Quantified Score

Hi-index	0.01

Visualization

Abstract

In this paper, we present an improved version of partial parallel interference cancellation (PPIC), called variance-reduced PPIC (VRPPIC), for multicarrier code division multiple access uplink systems. The VRPPIC detector is a combination of the PPIC receiver and a new bit estimator, where a simplified realization is derived for the main PPIC operations and soft decisions from PPIC are linearly combined by the bit estimator using appropriate weighting factors (derived from the PPIC weighting factors) to reduce the conditional variance of the final signal estimate. Also, we derive an optimal weighting factor (OWF) selection algorithm for VRPPIC based on minimizing a monotonically increasing conditional variance function. The derived OWFs for all the interference cancellation stages are equal and can easily be obtained from a linear function of the number of active users. Simulation results show that VRPPIC with the proposed OWFs significantly outperforms VRPPIC (or PPIC) with randomly selected weighting factors in multipath Rayleigh fading channels.