Abstract

Existing adaptive signal processors are typically implemented by using digital circuits and techniques and so are limited to 1 GHz or less. Fiber-optic signal processing, capable of much higher frequencies, has seen recent rapid development. Transversal filters are reconfigured by weight and/or time-delay control and typically require a plurality of control signals to set the weight or time delay of each signal to be summed. Here we demonstrate the performance of a novel tunable fiber-optic finite-impulse-response (FIR) filter with continuously variable unit time delays (Fig. 1). The FIR filter utilizes several taps with varying net chromatic dispersion (a fiber-optic prism) and an externally modulated wavelength-tunable source.¹

© 1995 Optical Society of America