“…To achieve more complicated diagnostic approaches for SHM applications, several sensors may work together in a systematically designed manner, forming a sensor network. Advanced damage imaging techniques have been developed by using the phased array [28,29] and sparse array [30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49]. Substantial research has focused on the research of damage imaging algorithms for damage localization and characterization, using a sparse PWAS array, including tomography [30,31,32], the delay-and-sum imaging method [33,34,35], the time-reversal imaging approach [36,37,38], correlation-based imaging algorithm [39,40], probabilistic and statistical imaging methods [41,42,43], and the minimum variance imaging method [44,45,46].…”