ABSTRACT
Estimating the directions of arrival (DOAs) of propagating plane waves is a requirement in a variety of applications including radar, mobile communications, sonar, and seismology. Due to its simplicity and high-resolution capability, estimation of signal parameters via rotational invariance techniques (ESPRIT) [23] has become one of the most popular signal subspace-based DOA or spatial frequency estimation schemes. ESPRIT is explicitly premised on a point source model for the sources and is restricted to use with array geometries that exhibit so-called invariances [23]. However, this requirement is not very restrictive as many of the common array geometries used in practice exhibit these invariances, or their output may be transformed to effect these invariances.
