1955/01/01 by A. G. Fox, S. E. Miller, Stewart E. Miller +1 · 2 citations
Engineering · #Electromagnetic Simulation and Numerical Methods
paper · doi:10.1002/j.1538-7305.1955.tb03763.x
crossref issued 1955/01/01 · crossref published 1955/01/01 · crossref published-print 1955/01/01 · openalex publication_date 1955/01/01 · crossref published-online 2013/07/29 · crossref created 2013/07/29 · crossref deposited 2020/10/14 · openalex created_date 2025/10/10 · crossref indexed 2026/07/30 · openalex updated_date 2026/07/30
The behavior and applications of ferrites in microwave circuits have been studied at the Holmdel Radio Laboratory with particular emphasis on non-reciprocal properties. There are numerous ways of building non-reciprocal devices which accomplish the same function, and the authors propose at the outset that a terminology based on function be adopted. Definitions of the gyrator, circulator and isolator are given. A qualitative method of deducing the properties of new ferrite-loaded circuits, termed “point-field” analysis, has been particularly fruitful, in that it permitted the exploration of a wide variety of ferrite-loaded circuits despite the absence of precise mathematical analyses. Faraday rotation in longitudinally-magnetized ferrite-loaded circuits has been studied; the effects of higher-order modes, the reasons for variation in Faraday rotation as a function of frequency, and the optimum geometry for the ferrite loading are discussed. In transversely-magnetized ferrite-loaded rectangular waveguide it is shown that the single mode medium may be non-reciprocal as to phase constant, attenuation constant, or distribution of field components in the cross-section. The latter effect is called the “field-displacement” effect. In transversely-magnetized ferrite-loaded round waveguide, either reciprocal or non-reciprocal birefringence may be achieved and examples are given. Some non-reciprocal ferrite-loaded dielectric waveguides are discussed. In all of these forms of non-reciprocal transmission media, gyrators, circulators and isolators may be built, and experimental data are reported on some of the possibilities. A brief review of prospective uses for these non-reciprocal elements is given.