A nine-tap transversal preamplifier using cascode MESFETs in a distributed structure has been designed for pulse shaping data, AGC and group delay control in high speed lightwave systems. The circuit was fabricated in a microwave monolithic integrated circuit (MMIC) implementation using 0.8 m GaAs MESFET technology. The AGC capability was demonstrated. The best noise measured for this preamplifier was 15 pA/ Hz.

No abstract

Transversal filters are a sub-class of finite impulse response (FIR) -infinite impulse response (IIR) filters. By using FIR-IIR filters one can reduce filter order and compensate for a larger variety of dispersion. It will be shown that the IIR filter can be used to compensate for chromatic dispersion. An example will be given of a 120km dispersion limited 10 Gb/s system in which the IIR filter was able to compensate for chromatic dispersion to extend the reach to 210km. An implementation of a FIR-IIR MMIC will also be shown and discussed.