Abstract: A resonator for use in a rectangular waveguide filter includes a first section of rectangular waveguide and a second section of rectangular waveguide that are arranged along a guide direction of the resonator and joined to each other to form the resonator. Walls of the second section of rectangular waveguide that extend in the guide direction are in a parallel relationship with respective walls of the first section of rectangular waveguide. A width of the first section of rectangular waveguide in a width direction is equal to a width of the second section of rectangular waveguide in the width direction so that the resonator has uniform width in the width direction. A height of the second section of rectangular waveguide in a height direction is smaller than a height of the first section of rectangular waveguide in the height direction.

Abstract: A group of rectangular waveguide resonators include first and second resonators that are arranged so that first lateral walls of the first resonator extend in parallel to second lateral walls of the second resonator. The first lateral walls correspond to broad sides of a first cross section of the first resonator perpendicular to a guide direction of the first resonator. The second lateral walls correspond to broad sides of a second cross section of the second resonator perpendicular to a guide direction of the second resonator. The first and second resonators are further arranged so that one of the first lateral walls at least partially faces one of the second lateral walls, and the first resonator is electromagnetically coupled to the second resonator through a first aperture in the one of the first lateral walls and a second aperture in the one of the second lateral walls.

Abstract: A microwave bandstop filter comprises a waveguide segment of cross-section that presents longitudinal variation of sinusoidal type modulated by an amplitude function that is continuous, the period of said longitudinal variation of sinusoidal type being the Bragg period for the fundamental guided mode at a center frequency of the band to be stopped. A filter assembly comprises a microwave lowpass filter presenting a cutoff frequency and at least one interfering passband at frequencies higher than said cutoff frequency, and at least one bandstop filter as defined above, connected to the output of said lowpass filter, in which the amplitude and the period of said longitudinal variation, and also the length over which it extends are such that they stop said interfering passband of said lowpass filter. An output multiplexer for a multichannel microwave transmitter includes such a filter assembly.

Abstract: A microwave bandstop filter comprises a waveguide segment of cross-section that presents longitudinal variation of sinusoidal type modulated by an amplitude function that is continuous, the period of said longitudinal variation of sinusoidal type being the Bragg period for the fundamental guided mode at a center frequency of the band to be stopped. A filter assembly comprises a microwave lowpass filter presenting a cutoff frequency and at least one interfering passband at frequencies higher than said cutoff frequency, and at least one bandstop filter as defined above, connected to the output of said lowpass filter, in which the amplitude and the period of said longitudinal variation, and also the length over which it extends are such that they stop said interfering passband of said lowpass filter. An output multiplexer for a multichannel microwave transmitter includes such a filter assembly.

Abstract: The invention provides a dual-mode microwave filter, comprising a rectangular resonator of length l, height b, and width a operating in two distinct modes (m, 0, n) and (p, 0, q) from a single family of modes and presenting the same direction as the E field, and wherein coupling and mode excitation discontinuities are inductive and in the same direction.

Abstract: The invention provides a dual-mode microwave filter, comprising a rectangular resonator of length l, height b, and width a operating in two distinct modes (m, 0, n) and (p, 0, q) from a single family of modes and presenting the same direction as the E field, and wherein coupling and mode excitation discontinuities are inductive and in the same direction.

Abstract: There is disclosed a method for designing an electrical filter comprising the steps of: a) selecting at least one determined function called seed function; b) determining the product of all these seed functions to define a transfer function generating function of the electrical filter; c) translating the electrical filter transfer function into transmission zeroes and poles; d) and synthesizing those electrical filter dimensions that achieve the required zeroes and poles. A particular application is aimed at a Chebycheff filter comprised of serially arranged resonant cavities and couplers, operating in the microwave range.

Abstract: The invention relates to a circular waveguide dual-mode filter comprising at least one element for adjusting a filter parameter. Said element is an elliptical waveguide portion disposed perpendicularly to the longitudinal axis of said circular waveguide. The filter may be coupled to an inlet circular waveguide and to an outlet circular waveguide.

Abstract: A system for synthesizing a microwave filter including a plurality of resonators having no tuning elements, in particular waveguide filters for use in satellite telecommunications networks. Signals representing the coupling coefficients of the coupling elements having a finite thickness and the resonant frequency of the resonators are stored in an electronic memory. A computation unit is controlled by a control unit arranged to determine automatically, in a single run, the widths of the coupling elements and the lengths of the resonators from the signals representing the coupling coefficients.