A novel in-line interferometric acousto-optic architecture for two-dimensional beam scanning of Planar phased arrays is demonstrated experimentally for a 330-MHz carrier. The required modulo-2pi phase control along the two orthogonal antenna-array directions is achieved by using two independent control frequencies f1 and f2 with frequency variations of 0-170 and 0-210 kHz, respectively. A processor output carrier signal-to-noise ratio of 48 dB at + 1-MHz offset is measured in an analyzer bandwidth of 300 kHz, with a carrier tuning range of 90 MHz.A novel in-line interferometric acousto-optic architecture for two-dimensional beam scanning of Planar phased arrays is demonstrated experimentally for a 330-MHz carrier. The required modulo-2pi phase control along the two orthogonal antenna-array directions is achieved by using two independent control frequencies f1 and f2 with frequency variations of 0-170 and 0-210 kHz, respectively. A processor output carrier signal-to-noise ratio of 48 dB at + 1-MHz offset is measured in an analyzer bandwidth of 300 kHz, with a carrier tuning range of 90 MHz.