Combined Parameter Estimation Using Nullsteering for DOA Estimation with KR Product Array Processing

Khatri-Rao (KR) product array processing can improve the angular and velocity resolution. Hence, it has been reported for various applications such as direction of arrival (DOA) estimation in marine radar. However, it has been reported that the cross-correlation of incoming waves deteriorates performance when correlated waves are incoming. Therefore, this poses a problem when applying the system to a radar. The cross-correlation component of the arriving waves is expressed as a combination of correlation coefficients and direction of incidence (combined parameters). In this study, we propose a DOA estimation method using combined parameter estimation using nullsteering with weights that direct nulls to the cross-correlation components of incoming waves. The aim is to mitigate the applicability of KR extension.