One major issue of implementing broadband active noise control systems in reverberant
rooms is the lack of reference signals. In this work, by exploiting the spatial sound
field characteristics, a time-domain sound field separation method is developed to
generate the reference signal for broadband active noise control systems in reverberant
rooms. The time-domain sound field separation method separates the outgoing field produced
by the primary source from the secondary source feedback and room reverberation on a
spherical array, based on spherical harmonic decomposition of the sound field and the
radial particle velocity measured by the array.