Detecting the number of sources using modified EIT

In array signal process field, Eigen Increment Threshold (EIT) was widely adopted for its better performance of number-detection than traditional AIC and MDL method. However, EIT has to face the challenge of detection probability (PD) descending while the power of sources is quite different. In this paper, after some analysis to the variety of the eigenvalue of auto-correlation matrix, a modification is introduced to improve the PD performance of EIT in the case of unequal power source. Computer simulation results show that the modification is efficient, and bring only tiny increase of computation.