ESPRIT and TAM (Toeplitz approximation method) are theoretically equivalent

ESPRIT (estimation of signal parameters by rotational invariance techniques) and TAM are two recently developed methods which can be applied to the problem of harmonic retrieval as well as to direction-of-arrival (DOA) estimation by an antenna array. It is shown that both methods rely on the same theoretical basis. For the DOA estimation problem, a modified version of TAM can be made comparable to ESPRIT, precision being gained at the expense of computational load. Theoretical considerations lead to a new method unifying TAM, ESPRIT, and the Tufts-Kumaresan orthogonal vector method