A bilinear approach to constant modulus blind equalization
Constantinos B. Papadias · 1993
We consider the problem of blind equalization of a constant modulus signal that is received in the presence of Inter-Symbol-Interference (ISI) and additive noise. A well-known class of adaptive algorithms for this problem is the so-called Godard family of blind equalizers[1], including among others the CMA[2] and SATO[3] algorithms. These algorithms are known for their ability in general to open the eye of a communications channel and for their low computational complexity. However, a common disadvantage of all algorithms of this class is that they might exhibit ill-convergence if not properly initialized, due to the non-convex form of their cost function. In this paper we present a different approach to the problem, namely, a bilinear approach in order to construct a convex cost function with a unique minimum point. After presenting the formulation for this approach, we show that in the case of an exactly invertible noiseless channel the optimal solution that completely opens the comm...