Abstract
Because of power limitations in single semiconductor devices, power combining is usually applied in the frequency ranges of short millimeter and of submillimeter waves. Multiple-device circuits are hence found for fundamental and harmonic frequency sources and for amplifiers using both signal splitting and combining circuits. In receiver technology, on the other hand, signal splitting circuits are also inherent to subharmonically pumped downconverters and to mixers for focal plane arrays. Hence a suitable multiple- device circuit technology is a necessary prerequisite for many--if not most--applications. Hence power combining and splitting are important circuit functions in the frequency bands of millimeter and submillimeter waves. It is shown that their tasks can almost ideally be fulfilled by using computer-generated holograms. The inherent features of this method are its scalability up to arbitrarily high frequencies, high circuit efficiency which almost approaches unity, broad bandwidth performance, robustness and simplicity of realized circuits. As examples, multi-device oscillators with Impatt-diodes, frequency multipliers with varactor diodes, and subharmonically pumped mixers with Schottky-diodes and arbitrary order of the subharmonic frequency are treated. Basic circuit configurations together with some preliminary experimental results are also presented. It is believed that utilizing the principles of holography in multiple device circuits will establish a new circuit technology for the short millimeter wave and submillimeter wave ranges which is characterized by high electrical performance, relatively simple circuits, and high flexibility and which simultaneously will overcome the problem of generating high enough output power levels from all-solid-state sources.
