A Non-Hermitian Joint Diagonalization based Blind Source Separation algorithm for Operational Modal Analysis

Second Order Blind Source Separation (SO-BSS) techniques possess several mathematical characteristics making them a viable option for Operational Modal Analysis (OMA). However, on closer scrutiny it is revealed that there are certain subtleties that limit their direct application to OMA applications. This paper continues from past work of the authors, which focussed on understanding SO-BSS techniques from a perspective of OMA applicability and developing SO-BSS based algorithm for OMA. In this paper, a new algorithm is proposed that overcomes the inherent limitations of SO-BSS algorithms with regards to their applicability to OMA. These limitations include applicability to heavily damped systems, identification of complex modes, and applicability to scenarios where number of available sensors is lesser than the number of modes to be estimated, etc. The algorithm’s advantage over original form of SO-BSS is demonstrated by means of an analytical example.