Estimation of phase velocity using array observation of microtremors with arbitrary shape

Abstract To estimate the phase velocity using array observations of microtremors, some algorithms for estimation include constraints on shape, such as equilateral triangles or placement receivers a circle, in order to reduce error velocity. In present study, direct technique is introduced records obtained through an with arbitrary shape based complex coherency function (CCF), where CCF defined normalized cross spectrum microtremor observed simultaneously by two receivers. The particle swarm optimization (PSO) method, one metaheuristic methods, applied and optimal values are provided other unknown parameters. Approximate representations stochastic properties variables analytically derived discrete representation CCF, case arrival directions microtremors treated random following uniform distribution. Furthermore, validity proposed method confirmed numerical simulations actual observation records. Graphical