On spatial smoothing of high resolution direction finding of real-valued sinusoidal signals

Spatial smoothing is a well-known method for high-resolution direction estimation, such as the MUSIC algorithm, of coherent sources. This method, however, was designed for complex-valued sinusoidal sources. In this paper we show that this spatial smoothing method equally applies to real-valued sinusoidal signal sources. A theoretical derivation as well as computer simulations are provided in this paper.