Vol. 42

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Nonsynchronous Noncommensurate Impedance Transformers

By Vitaliy Zhurbenko and Kseniya Kim
Progress In Electromagnetics Research B, Vol. 42, 405-424, 2012


Nonsynchronous noncommensurate impedance transformers consist of a combination of two types of transmission lines: transmission lines with a characteristic impedance equal to the impedance of the source, and transmission lines with a characteristic impedance equal to the load. The practical advantage of such transformers is that they can be constructed using sections of transmission lines with a limited variety of characteristic impedances. These transformers also provide comparatively compact size in applications where a wide transformation ratio is required. This paper presents the data which allows to estimate the achievable total electrical length and in-band reflection coefficient for transformers consisting of up to twelve transmission line sections in the range of transformation ratios r=1.5 to 10 and bandwidth ratios χ=2 to 20. This data is obtained using wave transmission matrix approach and experimentally verified by synthesizing a 12-section nonsynchronous noncommensurate impedance transformer. The measured characteristics of the transformer are compared to the characteristics of the conventional tapered line transformer.


Vitaliy Zhurbenko and Kseniya Kim, "Nonsynchronous Noncommensurate Impedance Transformers," Progress In Electromagnetics Research B, Vol. 42, 405-424, 2012.


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