A systematic synthesis method for lossy noise matching networks for ultra-low noise and flat-gain optical receivers is presented. The procedure utilises a topology from lossless matching network synthesis to obtain low noise, and introduces lossy network elements in the design to constrain the ripple variation of the gain to a specified value. An experimental tuned PIN-HEMT optical receiver with a gain flatness of /spl plusmn/0.8 dB over the entire frequency range and a measured average noise current of 5.04 pA//spl radic/(Hz) is demonstrated.
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