ABSTRACT
The problem of localization of sources radiating energy by observing their signal received at spatially separated sensors is of considerable importance, occurring in many fields, including radar, sonar, mobile communications, radio astronomy, and seismology. In this chapter, an estimation of the direction of arrival (DOA) of narrowband sources of the same central frequency, located in the far field of an array of sensors is considered, and various DOA estimation methods are described, compared, and sensitivity to various perturbations is analyzed. The chapter also contains discussion of various preprocessing and source estimation methods [God96, God97]. Source direction is parameterized by the variable
q
. The DOA estimation methods considered include spectral estimation, minimum-variance distortionless response estimator, linear prediction, maximum entropy, and maximum likelihood. Various eigenstructure methods are also described, including many versions of MUSIC algorithms, minimum norm methods, CLOSEST method, ESPRIT method, and the weighted subspace fitting method.
