A Constrained Tensor-Based Approach for MIMO NL-CDMA Systems
In this paper, the authors propose a deterministic tensor-based approach for joint channel and symbol estimation in the context of multiuser multi-antenna (MIMO) CDMA communication systems. They use a new NonLinear (NL) coding allowing obtaining a third-order block-Tucker2 model for the signals received by multiple receive antennas, with a constrained structure for the core tensors that ensures the uniqueness of the tensor model. Two types of receiver are developed. First, assuming that the users' code matrices are mutually orthogonal and known at the receiver, they derive a blind algorithm composed of two steps: a separation of users' contributions in the received signals, with decoding, followed by a blind channel and symbol estimation for each user separately.