THE performance and robust implementation of a blind CMOE receiver for MC-CDMA systems

This paper studies a new robust constrained minimum output energy (CMOE)-based blind detector for multicarrier code division multiple access (MC-CDMA) systems. The proposed receiver intends to minimize the receiver's output energy while preserving the components of the desired user. By imposing quadratic weight constraints, the CMOE detector is made more robust against signal modeling errors, and a better performance over the standard CMOE detector is obtained. Steady-state signal-to-interference-plus-noise ratio (SINR) analysis of the blind CMOE detector and the minimum mean-squared error (MMSE) method with training sequences is presented. Numerical results show that the performance of the new robust detector is comparable to subspace-based method using exact singular value decomposition (SVD).published_or_final_versio

A group-blind multiuser receiver for MC-CDMA systems

In this paper, a group-blind multiuser receiver is investigated for multicarrier code division multiple access (MC-CDMA) systems. In uplink transmissions, the receiver has the knowledge of the spreading sequences of the users within the cell, while the spreading sequences of the users from other cells are unknown. By imposing linear vector constraints on the multiuser detector, group-blind detection can efficiently suppress the known interferers, while mitigating the unknown interferers based on the minimum mean square error (MMSE) principle. A subspace-based channel estimation algorithm is proposed to blindly estimate the channel information. An adaptive implementation of the group-blind multiuser detection is also developed by using signal and noise subspace tracking algorithms. Numerical results show that the performance of the group-blind detector is much better than the subspace-based blind linear MMSE detector.published_or_final_versio