“…Given the interest of performing reliable acoustic measurements in aerodynamic wind tunnels, many efforts have been made for years to reduce the background noise in closed test sections 1, 2, 3 , to improve inflow acoustic measurements 4,5 and to develop data dereverberation techniques 6,7,8 . In particular, beamforming techniques based on the free-field Green's function may be able to provide noise source levels in reverberating test sections 9,10,11,12 . Dereverberation is indeed achieved through the focusing performance of beamforming, that enables to spatially separate real acoustic sources within the test section and their images located outside the test section 9,11 .…”