Characterization of a ferroelectric liquid crystal-based time delay unit for phased array antenna applications

An experimental demonstration of a photonic time delay unit (PTDU) based on ferroelectric liquid crystal devices and Thompson polarization beamsplitters (TBSs) is presented. High signal-to-noise ratios (SNRs) (>96 dB) and optical polarization extinction ratios (ER,/spl sim/40 dB) are demonstrated for the PTDU using an active noise filter technique. Using a 5 V peak square wave switch drive signal, a 70 /spl mu/s switching speed is demonstrated for this PTDU that can be used in fast (e.g., 5000 beam/s) beam scanning phased array systems. A shorter switching speed of 35 /spl mu/s is also observed using a high 15 V peak transitional voltage driving signal.

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