Design of Microwave Filters, Impedance-Matching Networks, and Coupling Structures. Volume 2

Abstract

OF VOLUMES I AND ]aThis book presents design techniques for a wide variety of low-pass, band-pass, high-pass, and band-stop microwave filters; for multiplexers; and for certain kinds of directional couplers. The material is organized to be used by the designer who needs to work out a specific design quickly, with a minimum of reading, as well as by the engineer who wants a deeper understanding of the design techniques used, so that he can apply them to new and unusual situations.Most of the design procedures described make use of either a lumpedelement low-pass prototype filter or a step-transformer prototype as a basis for design. Using these prototypes, microwave filters can be obtained which derive response characteristics (such as a Tchebyscheff attenuation ripples in the pass band) from their prototype. Prototype filter designs are tabulated, and data is given relevant to the use of prototype filters as a basis for the design of impedance-matching networks and time-delay networks. Design formulas and tables for step-transfor,.er prototypes are alsc given.The design of microwave filter structures to serve as impedancematching networks is discussed, and examples are presented. The techniques described should find application in the design of impedance-matching networks for use in microwave devices such as tubes, parametric devices, antennas, etc., in order to achieve efficient broad-band operation. The design of microwave filters to achieve various time-delay (or slow-wave)properties is also discussed.Various equations, graphs, and tables are collected together relevant to the design of coaxial lines, strip-lines, waveguides, parallel-coupled lines between common ground planes, arrays of lines between ground planes, coupling and junction discontinuities, and resonators. Techniques for measuring the Q's of resonators and the coupling coefficients between resonators are also discussed, along with procedures for tuning filters. Equations and principles useful in the analysis of filters are collected iii together for easy reference and to aid the reader whose bakgrcund for the subject matter of this book may contain some gaps.Diroctionot filters have special advantages for certain applications, and are treated in detail in a separate chapter, as are highpower filters.-, Tunable filters of the kind that might be desired for preselector applications are also treated. Both mechanically tunable filters and filters using ferrimagsnetic resonatorq, which can be tuned by varying a biasing magnetic field, are discussed.A, PMFA E TO VOWMES I AND 11The organization of this book has three general objectives. The first objective is to present fundamental concepts, techniques, and data that are of general use in the design of the wide range of microwave structures discussed in this book. The second objective is to present specialized data in more or less handbook form so that a designer can work out practical designs for structures having certain specific configurations, without having to recreate the design theory o...

On the Use of Gegenbauer Prototypes in the Synthesis of Waveguide Filters

“…The specifications on amplitude are accomplished by a Chebyshev prototype of order 6 [8]. Unfortunately, this solution does not satisfy the group delay requirements.…”

Single loop multi-gap resonator for whole body EPR imaging of mice at 1.2GHz

“…The equation for the resonator frequency is as follows: this allows us to estimate the physical parameters of the resonator, the area and the thickness of the resonator gaps). However, the increased number of resonator gaps should cause deterioration of the quality factor of the empty resonator, according to Q=iωL/R, where R is the resistance of one section of the resonator (25). If one considers only resistive loss in the conductors, Q will drop because of the decrease of the resonator inductance.…”

“…The dimensions of the resonator were chosen in order to accommodate and obtain EPR images of the whole body of a living mouse, which requires at least ~30 mm diameter. This resonator was designed with EPR/NMR co-imaging experiments in mind, with ability of the resonators to slide over the fixed sample utilizing a special stage, providing a method to maintain alignment between gradients and sample while exchanging EPR or NMR resonators over the sample (25). Special provisions for EPR/NMR co-imaging with requisite sliding mechanism, require support for the sample holder, therefore the inner diameter of the resonator had to be increased to 42 mm.…”

Practical Design of Filters Using Ebg Waveguides Periodically Loaded With Metal Ridges

“…These EBG ridged waveguide structures have a pass-band performance starting from the cut-off frequency of the housing waveguide, whereas the upper cutoff is defined from the unit cell dimensions together with the gap between the ridges. Even though the resulting response is pass-band in frequency terms, in microwave terminology it is commonly referred as a low-pass characteristic since it starts from the first frequency where the waveguide ports effectively propagate [9].…”