Abstract:This paper considers blind interference suppression for a space-time block coded MultiCarrier CDMA (MC-CDMA) system. By investigating the code space in frequency domain and the data vector space of the multipath signals, the noise-subspace-based approach is used to perform blind channel estimation. A modified ULV updating algorithm is applied to performing noise subspace tracking. The algorithm does not require rank estimation of the correlation matrix, and estimate directly the noise subspace. To suppress Multiuser Access Interference (MAI), a Projection-based Auxiliary Vector (PAV) algorithm is proposed. A reconstructed Maximum Ratio Combining (MRC) filtering vector can be evaluated by using the outputs of the last filtering vector. Taking the orthogonal projection of the reconstructed filtering vector onto the space spanned by the basic filtering vector and the previously derived auxiliary vector as an auxiliary vector, a new filtering vector can be formed by linearly combining the last filtering vector and newly generated auxiliary vector. Simulation results show the effectiveness of the proposed algorithms.