R. E. Semernya – Post-graduate student, Bauman Moscow State Technical University; Junior Research Scientist of Bauman Moscow State Technical University Research Institute, Leading Design Engineer in LLC “Radiocomp”

E-mail: semernyare@gmail.com

S. L. Chernyshev – Dr.Sc. (Eng.), Professor, Bauman Moscow State Technical University

A. R. Vilenskij – Ph.D. (Eng.), Associate Professor, Bauman Moscow State Technical University; Leading Engineer, Samsung Research Institute Russia

V. V. Kuvshinov – Ph.D. (Eng.), Head of Department of Microwave Filters, LLC “Radiocomp”

The design procedure of quasi-elliptic passband filters for the LTE band (2170–2200 MHz) with high 3G band rejection has been presented. The general coupling matrix has been synthesized by applying a dedicated recursive technique. We propose a practical design for electrical coupling enhancement between air cavity combline resonators using a suspended substrate with printed conducting strips. First, scattering parameters of the designed filters have been obtained during simulations in Ansys HFSS. Next, a filter prototype has been fabricated and measured. Experimental and simulated results demonstrate perfect agreement. Finally, we have explored temperature stability of filter electrical performance.

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