Photoconductor receiver sensitivity.

The various contributions to photoconductor noise are calculated and are used to determine the sensitivity of digital photoconductor receivers for use in lightwave communication systems. We find that Johnson noise is the most significant source of noise current up to bit rates as high as 4 Gb/s, above which FET channel noise becomes dominant. In comparing the results obtained for ideal photoconductive receivers with receivers employing pin photodetectors, we find that the sensitivities of both circuits are comparable, provided that low capacitance pin receivers are employed.