Joint order detection and blind channel estimation by least squares smoothing

A joint order detection and blind estimation algorithm for single input multiple output channels is proposed. By exploiting the isomorphic relation between the channel input and output subspaces, it is shown that the channel order and channel impulse response are uniquely determined by finite least squares smoothing error sequence in the absence of noise. The proposed subspace algorithm is shown to have marked improvement over existing algorithms in performance and robustness in simulations.