Local Multipoint Distribution Service (LMDS) is a broadband microwave communications technology offering a low-cost and multifunctional solution for terminal access applications. This paper develops a rectangular waveguide-based duplexer with a square-ridge T-junction for LMDS. The design of a rectangular waveguide-based metal diaphragm filter in the E-plane is described. The metal diaphragm of this filter can be processed using methods such as etching, ensuring high precision and low cost. The characteristics of a rectangular waveguide-based T-junction in the H-plane used in the duplexer are analyzed.

Keywords: microwave duplexer, E-plane metal diaphragm, microwave filter, ribbed T-junction, local multi-drop distribution service

The problem of developing a compact and narrow-band waveguide filters in the rectangular waveguides with two centrally symmetric L-crests is solved. The aim of this article is the experimental verification of the results of computer simulation of the properties of thin metal diaphragms with a elaborate aperture. The experimental results confirm the effectiveness of the developed theoretical algorithms and make possible to use proposed thin metal diaphragms as basic elements in design of compact waveguide band-pass and band-locking filters.

Keywords: resonant diaphragm filter, the waveguide band-pass filter, band-barrier filter.

The possibilities of waveguide elements realization in the structure of multilayered integrated chips of centimeter and millimeter ranges with SIW (Substrate Integrated Waveguide)-technology application are considered. The approaches allowing effectively using in new structures the algorithms and techniques of the electrodynamic analysis and synthesis of passive devices on classical all-metal waveguides are offered. Advantages of use in SIW structure the waveguides of complex cross-section are considered on the example of the microwave band-pass filter.

Keywords: A.A. Gadzieva, V.V. Zemlyakov, S.V. Krutiev