Distributed PARAFAC based DS-CDMA blind receiver for wireless sensor networks

International audienceIn this paper, we consider a collaborative scheme in wireless sensor networks where the multiple access protocol is a DS-CDMA one. When the receiver is equipped with an antenna array, it has been shown that efficient blind receivers can be derived using the PARAFAC tensor model. In general, the parameters of the PARAFAC model are fitted using an alternating least squares algorithm. Herein, we consider the case where each receiver has a single antenna. Therefore, by allowing collaboration in a predefined neighborhood, we derive a distributed alternating least squares algorithm including some average consensus steps

Approximate Rank-Detecting Factorization of Low-Rank Tensors

We present an algorithm, AROFAC2, which detects the (CP-)rank of a degree 3 tensor and calculates its factorization into rank-one components. We provide generative conditions for the algorithm to work and demonstrate on both synthetic and real world data that AROFAC2 is a potentially outperforming alternative to the gold standard PARAFAC over which it has the advantages that it can intrinsically detect the true rank, avoids spurious components, and is stable with respect to outliers and non-Gaussian noise

Non-iterative solution for PARAFAC with a Toeplitz matrix factor

International audienceRecently, tensor signal processing has received an increased attention, particularly in the context of wireless communication applications. The so-called PARAllel FACtor (PARAFAC) decomposition is certainly the most used tensor tool. In general, the parameter estimation of a PARAFAC decomposition is carried out by means of the iterative ALS algorithm, which exhibits the following main drawbacks: convergence towards local minima, a high number of iterations for convergence, and difficulty to take, optimally, special matrix structures into account. In this paper, we propose a non-iterative parameter estimation method for a PARAFAC decomposition when one matrix factor has a Toeplitz structure, a situation that is commonly encountered in signal processing applications. We illustrate the proposed method by means of simulation results