  This paper proposes an auxiliary vector filtering (AVF) algorithm based on a
constrained constant modulus (CCM) design for robust adaptive beamforming. This
scheme provides an efficient way to deal with filters with a large number of
elements. The proposed beamformer decomposes the adaptive filter into a
constrained (reference vector filters) and an unconstrained (auxiliary vector
filters) components. The weight vector is iterated by subtracting the scaling
auxiliary vector from the reference vector. The scalar factor and the auxiliary
vector depend on each other and are jointly calculated according to the CCM
criterion. The proposed robust AVF algorithm provides an iterative exchange of
information between the scalar factor and the auxiliary vector and thus leads
to a fast convergence and an improved steady-state performance over the
existing techniques. Simulations are performed to show the performance and the
robustness of the proposed scheme and algorithm in several scenarios.
