Resolution threshold for coherent sources using smoothed eigenstructure methods

The paper presents a performance analysis of certain eigenstructure based methods (MUSIC type) with suitable forward-only and forward/backward smoothing schemes employed to decorrelated coherent sources. Bias and resolution thresholds are derived for two coherent sources with different phase and unequal power. The effect of phase difference and power ratio on the resolution threshold is discussed. For the case of forward/backward smoothing and two coherent sources with same phase and equal power, the resolution threshold reduces to that obtained by Pillai et al. Detailed computer simulations which confirm the analysis are also presented.