Demonstration of a photonic space switch utilizing acousto-optic elements

A multicasting photonic space switch is proposed and demonstrated utilizing acousto-optic Bragg cells in a free-space active splitting, passive combining optical architecture. A 4 x 4 switch is demonstrated at optical wavelength X = 0.83pm using Te02 Bragg cells. Fiber-to-fiber insertion loss of 15 dB, crosstalk of -20 dB, extinction ratio of >30 dB, and polarization sensitivity of 0.8 dB has been measured. Feasibility of switch operation at 1.3 m is also shown for Te02. Although this design was fabricated as a 4x4, expansion to 14x 14 can be accommodated with modifications to the optical element design. Calculations indicate that a maximum switch size of 20 x 20 and an insertion loss of 11 dB is possible, with crosstalk and extinction ratios greater than 30 dB.