HOS-Based Semi-Blind Spatial Equalization for MIMO Rayleigh Fading Channels

In this paper we concentrate on the direct semi-blind spatial equalizer design for MIMO systems with Rayleigh fading channels. Our aim is to develop an algorithm which can outperform the classical training based method with the same training information used, and avoid the problems of low convergence speed and local minima due to pure blind methods. A general semi-blind cost function is first constructed which incorporates both the training information from the known data and some kind of higher order statistics (HOS) from the unknown sequence. Then, based on the developed cost function, we propose two semi-blind iterative and adaptive algorithms to find the desired spatial equalizer. To further improve the performance and convergence speed of the proposed adaptive method, we propose a technique to find the optimal choice of step size. Furthermore a constrained Cramer-Rao bound (CRB) is developed for the addressed semi-blind signal model to evaluate the performance of the algorithms. ...

• Type: Journal
• Year: 2008
• Where: TSP
• Authors: Zhiguo Ding, Tharmalingam Ratnarajah, Colin Cowan
• Keywords: Algorithms, Convergence Speed, Spatial Equalizer, TSP 2008