Reciprocity in silicon Schottky-barrier diodes

Reciprocity has been examined at X band for low-noise silicon Schottky-barrier diodes by measuring the forward (r.f. to i.f.) and reverse (i.f. to r.f.) conversion losses by the heterodyne method. Reciprocity held for the silicon Schottky-barrier diodes, proving that their low conversion-loss behaviour is due to the nonlinear barrier resistance and not to parametric amplification caused by a nonlinear barrier capacitance. For comparison, silicon epitaxial point-contact and germanium point-contact diodes were also examined.