FIG. 1. Schematic diagram of the proposed fiber optic delay line based microwave photonic filter with negative or positive coefficients.
FIG. 2. Experimental setup for the frequency response measurement of the proposed microwave photonic filter.
FIG. 3. Measured waveforms with time-delay difference generated by the fiber optic delay line (a) CROSS-BAR state (b) BAR-CROSS state. The EOM1 and EOM2 are biased at 2.0 V.
FIG. 4. The frequency responses of the proposed filter when VEOM1 = 2.0 V, VEOM2 = 4.0 V and the columns of the fiber optic delay line are in the (a) CROSS-BAR states (b) BAR-CROSS states (c) CROSS-CROSS states. Theory (solid line) and Experiment (dot).
FIG. 5. The frequency responses of the proposed filter when VEOM1 = 2.0 V, VEOM2 = 2.0 V and the columns of the fiber optic delay line are in the (a) CROSS-BAR states (b) BAR-CROSS states (c) CROSS-CROSS states. Theory (solid line) and Experiment (hole).
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