Ultimate Noise Figure and Conversion Loss of the Schottky Barrier Mixer Diode

Considerable interest has recently been shown in the use of the epitaxial Schottky barrier (ESBAR) diode as a microwave frequent y down-converter. For the first time it has become possible to surpass the performance of the redoubtable point-contact diodes, through the use of photo resist techniques to achieve small areas and epitaxial material to achieve low series resistance . The new diodes are also more reproducible, have much lower reverse current leakage, lower l/f noise, and can be designed for much higher dynamic range . Herein we calculate that they should exhibit overall calculated noise figures as low as 3 dB at X-band when the image is short-circuited and the following i-f amplifier has a 2 db noise figure.