The peculiarities of the multibeam acousto-optic Bragg diffraction of light by a multifrequency acoustic signal are investigated. The investigation is related to design of fiber-optic space division switch multiplexer 1xN. It is proved that a specialized two-dimensional acousto-optic deflector can perform high efficiency multifunctional light switching of fiber-optic channels. The device has advanced characteristics--the number of channels is up to a few hundred, the switching time is about a few microseconds, and the cross talk is limited to -45 dB.