Abstract: A conducting film is formed on a dielectric block in a dielectric waveguide resonator, and a through-hole is formed in the dielectric block. The unloaded Q is set by selecting the outside dimensions of the dielectric block. The resonance frequency is set by selecting the size and location of the through-hole as well as the outside dimensions of the dielectric block. A terminal electrode is formed on a side surface of the dielectric block. A coupling hole is formed in the dielectric block and a coupling electrode is formed on the inner surface of the coupling hole. One end of the coupling electrode is connected to the terminal electrode and the coupling electrode extends toward the conducting film formed on the opposite side surface and one end surface of the dielectric block. The above structure allows an increase in the degree of freedom in the design of the characteristics including the resonance frequency and unloaded Q of the dielectric waveguide resonator.

Abstract: A conducting film is formed on a dielectric block in a dielectric waveguide resonator, and a through-hole is formed in the dielectric block. The unloaded Q is set by selecting the outside dimensions of the dielectric block. The resonance frequency is set by selecting the size and location of the through-hole as well as the outside dimensions of the dielectric block. A terminal electrode is formed on the outer surface of the dielectric block. A coupling hole is formed in the dielectric block and a coupling electrode is formed on the inner surface of the coupling hole. One end of the coupling electrode is connected to the terminal electrode and the other end of the coupling electrode is either connected to the conducting film formed on the outer surface of the dielectric block or terminated inside the dielectric block. The above structure allows an increase in the degree of freedom in the design of the characteristics including the resonance frequency and unloaded Q of the dielectric waveguide resonator.

Abstract: A cryogenic waveguide cavity filter for use in a wireless communication systems.

Abstract: A filter device including a metal cavity (1, 11) closed by two end walls (3a, 3b; 13, 13b) extending transversely relative to the axis of said cavity (1, 11) and at least two dielectric inserts (4a, 4b; 14a to 14d) defining a resonator (5, 15a, 15b) in said cavity, characterized in that it includes at least one coupling iris (7a, 7b; 17) which also extends transversely relative to said axis.

Abstract: A duplexer for microwave signals that requires no system of settings by screws. The duplexer includes two tunnels, each having a longitudinal passage and compartments demarcated by transversal partition walls. The compartments, the longitudinal passages and the common part are hollowed out in the plane upper surface of a monolithic block. The tunnels are closed on the top by a lid that adheres uniformly to the plane surface.

Abstract: A waveguide filter includes one or more resonator cavities which extend between an input to the filter and an output from the filter. Each resonator cavity in the filter has a center line with a chosen extension and a mechanical length. The mechanical length of the center line of each resonator cavity forms one of the parameters that determine the electrical length of the resonator cavity. The filter forms part of a microwave unit. At least one of the resonator cavities of the filter has a curved extension with respect to its center line.

Abstract: A conducting film is formed on a dielectric block in a dielectric waveguide resonator, and through-holes are formed in the dielectric block. The unloaded Q is set by selecting the outside dimensions of the dielectric block. The resonance frequency is set by selecting the size and location of the through-holes as well as the outside dimensions of the dielectric block. Terminal electrodes are formed on the outer surface of the dielectric block. Coupling electrodes are formed on the inner surfaces of the through-holes. One end of each coupling electrode is connected to the corresponding terminal electrode and the other end of the coupling electrode may be connected to the conducting film formed on the outer surface of the dielectric block. Alternatively, the other end of the coupling electrode may be partially removed to adjust the amount of coupling; or may be completely removed so as to isolate the coupling electrode from the conducting film on the outer surface.

Abstract: A multilayer dielectric evanescent mode waveguide bandpass filter with resonators utilizing via hole technology is capable of achieving very narrow bandwidths with minimal insertion loss and high selectivity at microwave frequencies is provided. The resonators may also be used as feed posts. A typical implementation of this filter is fabricated with soft substrate multilayer dielectrics with high dielectric constant ceramics. This filter typically takes up less space than other filters presently available. A typical implementation operates at a center frequency of 1 GHz, although other center frequencies, such as approximately 0.5 GHz to approximately 60 GHz, are achievable. The perimeter of the filter may be defined by via holes or plated slots.

Abstract: A transverse-electric waveguide filter is provided for transmitting a fundamental transverse-electric mode in a first frequency band while attenuating an associated higher-order transverse-electric mode in a second frequency band. The filter includes transverse corrugations between input and output waveguide ports to attenuate the higher-order transverse-electric mode. The input and output waveguide ports have a characteristic impedance and the filter also incudes a ridge system that is coupled between the first and second waveguide ports and is configured to provide a signal-path impedance that substantially matches the characteristic impedance to thereby support transmission of the fundamental transverse-electric mode from the input port to the output port.

Abstract: A coaxial dielectric filter comprising a straight cutoff waveguide, at least two coaxial dielectric resonators disposed coaxially or substantially coaxially and at an interval in the cutoff waveguide in its lengthwise direction, a rod-like input-side antenna whose leading end stands close, or inserted, to the inside of an input-side inner conductor of the coaxial dielectric resonator disposed on the input side, and a rod-like output-side antenna whose leading end stands close, or inserted, to the inside of an output-side inner conductor of the coaxial dielectric resonator disposed on the output side. This filter is characterized in that an adjacent-side end of at least one of coaxial dielectric resonators adjacent to each other forms a slope which is inclined with respect to the cutoff waveguide in its cross section perpendicular to the lengthwise direction.

Abstract: A toploading weighing apparatus which determines weight loss for a sample by drying the sample in a cylindrical microwave with a specific structure.

Abstract: A microwave filter has first and second subfilters. Each subfilter has at least one single mode resonator and a preset electrical response. The second subfilter is cascaded to the first subfilter by coupling one of the at least one single mode resonator of the first subfilter to one of the at least one single mode resonator of the second subfilter. The microwave filter has an overall transfer function dependent upon the selection of the first and second subfilters from a plurality of subfilters having different preset electrical responses.

Abstract: A dielectric waveguide which has a pair of dielectric substrates affixed to each other and a pair of electrically-conductive layers on the external surfaces of the two dielectric substrates. Each dielectric substrate has a projecting part that is thicker than other parts. A propagating region is formed where the projecting parts on the two opposing dielectric substrates are put together. Furthermore, a circuit is formed on the contact surface between the dielectric substrates. The circuit may include an electronic component. A part of the circuit is arranged in the propagating region so as to provide electromagnetic-field coupling between the circuit and the dielectric waveguide.

Abstract: A conducting film is formed on a dielectric block in a dielectric waveguide resonator, and a through-hole is formed in the dielectric block. The unloaded Q is set by selecting the outside dimensions of the dielectric block. The resonance frequency is set by selecting the size and location of the through-hole as well as the outside dimensions of the dielectric block. A terminal electrode is formed on the outer surface of the dielectric block. A coupling hole is formed in the dielectric block and a coupling electrode is formed on the inner surface of the coupling hole. One end of the coupling electrode is connected to the terminal electrode and the other end of the coupling electrode is connected to the conducting film formed on the outer surface of the dielectric block. The above structure increases the degree of freedom in the design of the characteristics, including the resonance frequency and unloaded Q, of the dielectric waveguide resonator.

Abstract: An NRD waveguide band-pass filter apparatus is provided which is simple in construction, which can be easily manufactured as well as being small in size and light in weight, and which operates in a single operating mode. The NRD waveguide band-pass filter apparatus includes a plurality of NRD waveguide resonators arrayed in such a way that each two adjacent NRD waveguide resonators are electromagnetically coupled to each other. A plurality of arrayed rectangular dielectric waveguides are interposed between an upper surface portion and a lower surface portion of a rectangular dielectric housing, which are parallel to each other. The upper surface portion and the lower surface portion and the plurality of arrayed rectangular dielectric waveguides are formed integrally, thus forming the housing. A first superconducting electrode and a second superconducting electrode are formed on the outer surfaces of the upper surface portion and the lower surface portion, respectively.

Abstract: An antenna-shared distributor is provided such that a non-conductor section is provided in a part of two conductor planes, a dielectric resonator which resonates in the HE111 mode is disposed between the conductor planes, and first and second dielectric strips whose respective end portions face the dielectric resonator are disposed, forming first and second dielectric lines and further, a voltage-controlled oscillator and a mixer are connected to the first and second dielectric lines, respectively.

Abstract: A microwave circular waveguide cavity and filter containing said cavity has a circular iris mounted transversely within the cavity. The iris has an eccentrically located circular aperture that is sized and located to control coupling between modes resonating in the cavity. The cavity can be a dual mode cavity, a triple mode cavity or a higher mode cavity. In a method of constructing such a cavity, coupling can be controlled by choosing from a number of variables including the size of the aperture, the offset distance, the inclination angle, the thickness and the location of the iris within the cavity.

Abstract: A dielectric filter includes a pair of transverse electric (TE).sub.10 -mode resonators connected in series. Each resonator has a conductor formed on substantially the entire surface of a dielectric body. On the connection surfaces of the resonators are formed grooves, respectively. On the inner surfaces of the grooves, central gaps are formed in the conductors. The pair of resonators are connected at their connection surfaces to combine the grooves to form a coupling-adjustment hole having an axis parallel to the interface between the resonators. The gaps combine to form a coupling window. The groove form a coupling-adjustment hole, through which the coupling window is accessible for being adjusted. The coupling window electromagnetically couples the pair of resonators.

Abstract: An electromagnetic resonator comprises a waveguide body having a generally tubular side wall and a pair of end wall assemblies. The end wall assembly includes a bowed aluminum plate and an INVAR disk, attached to one another at the periphery thereof. The INVAR disk includes a relatively thick outer annular portion and a relatively thin inner circular portion. The bowed aluminum plate bows in response to increased temperature, thereby counteracting expansion of the waveguide body.

Abstract: A microwave monolithic integrated circuit includes a coplanar waveguide (CPW) formed by a composite silicon structure constituted by a relatively high resistivity substrate, a first oxide layer on the upper surface thereof, a relatively thin silicon layer formed on the surface of the first oxide layer, and a very thin second oxide layer formed on the surface of the thin silicon layer. The silicon layer and the first oxide layer on which it is formed constitutes a silicon-on-insulator or SOI structure. A metallic signal line and ground planes are bonded to the surface of the second oxide layer. The zone of the thin silicon layer which extends between the ground planes is doped with an active impurity to produce high conductivity therein. As a result, the electric component of a quasi-TEM wave traversing the waveguide is substantially restricted to the thin silicon layer and does not penetrate to the underlying bulk silicon substrate.

Abstract: A multiplexer comprises a number of directional filters 17.sub.n connected to a transmission line feeding an antenna 2, 3. Signals to be multiplexed fed to the filters 17.sub.n may be sent via respective switches 16.sub.n. Unlike prior multiplexers where each directional filter defines a respective channel of the multiplex, the channels of the multiplexer of the invention, apart from one at the end, are defined by the band pass response of one directional filter and the band stop response of another directional filter, since the band pass responses of the directional filters from the input connected to the switch to the output connected to the transmission line, and the corresponding band stop responses between the two output ports connected to the transmission line, overlap each other. The same arrangement may be used for demultiplexing.

Abstract: A ceramic waveguide filter made from a monolithic block of dielectric ceramic material which has longitudinally spaced resonators is described. Resonant structures having a grounded portion and ungrounded portion, each of the resonant structures being inductively coupled at the ungrounded portion describe the electrical schematic which corresponds to the waveguide filter. The positioning of the input and output on the block of dielectric ceramic material define a passband and also create a shunt resonant section. The shunt resonant section is associated with a shunt zero in the electrical schematic of the waveguide filter. Finally, the dielectric block of ceramic is mostly coated with an electrically conductive coating material with the exception of an uncoated area immediately surrounding the input and output.

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 temperature compensated microwave filter has end caps and irises that each contain a projection that extends into a cavity to reduce the volume change of the cavity that would otherwise occur with changes in temperature due to an expansion or contraction of the side walls. The end caps and irises are formed from a single material. The material has a more positive coefficient of thermal expansion than the coefficient of thermal expansion of the side walls of each cavity. While one material is used to make up each end cap or iris, it is not necessary that the same material be used for all of the end cap and iris components.

Abstract: A multi-mode, typically triple-mode, cavity (1), for waveguide band-pass filters is disclosed, which cavity requires no tuning or coupling screws and rounded. The cavity comprises a waveguide element such as an iris (IR1) or a waveguide segment (CR2) arranged in a generically eccentric position with respect to the general development of the cavity and in particular to the main axis (Z) of the same. The cavity may be used to make narrowband filters for satellite communications. A filter comprising cavities (1) of the type described can be designed entirely using an electronic computer and requires no calibration procedure.

Abstract: An inductive strip waveguide band-pass filter includes a conductive movable wall which can be set to various positions to allow a varying "A" dimension, thereby setting controllably the center frequency of the filter over a predetermined range. If the inductive strip filter includes multiple synchronized resonant cavities, the resonant cavities remain synchronized for all positions of the movable wall. The position of the movable wall can be set manually or by a motorized control mechanism.

Abstract: The cavity has at least one waveguide segment with elliptical cross section whose axes are arranged at a given inclination angle (.alpha.) with respect to the polarization of the incident TE field. Thus a dual-mode cavity is realized, with the ability to let resonate two transverse fields (TE) with polarization planes orthogonal to each other. By adding a waveguide element able to introduce a non-axial discontinuity, a triple-mode cavity is obtained, allowing for an additional longitudinal mode to resonate as well.

Abstract: A pseudo-elliptical filter includes positively coupled resonant cavities, the signal input and the signal output of each cavity being at 90.degree. to each other. At least one retro-coupling of signal between two of said cavities is constituted by a waveguide. Applications include pseudo-elliptical filters operating in the millimeter band.

Abstract: A distributed TEM resonator band pass filter has a set of rod-shaped resonators arranged in an interdigital line with alternate ones of the resonators being grounded to opposite walls of a housing. Each resonator has an ungrounded end which is capacitively coupled to a wall of the housing. Partitions, grounded to the housing, are located between successive ones of the resonators. Each partition closes off only a portion of the space between neighboring resonators to leave a coupling aperture. The interdigital arrangement provides for reduced loss and a higher Q. Input and output ports are provided at opposite ends of the interdigital line. The resonators may be constructed in the form of a suspended substrate, a stripline, or a microstrip configuration.

Abstract: An electromagnetic bandstop filter comprises a microwave circuit, at least one microwave resonator, coupling means that couples electromagnetic energy to and from the microwave resonator, and an impedance transformer coupled to, and in series with, the coupling means, wherein the transformer is coupled to the resonator only through the coupling means, and wherein the impedance transformer is shunt coupled to the microwave circuit. The impedance transformer comprises at least two series-connected transmission line sections of different impedances.

Abstract: An electromagnetic resonator comprises an interior wall defining a substantially cylindrical cavity having a major axis. The interior wall includes first and second coupling grooves substantially parallel to the major axis. For a lesser level of coupling, the coupling grooves may be shorter than the length of the resonator and/or the second coupling groove may be omitted.

Abstract: In a TM dual mode dielectric resonator apparatus, a cross-shaped TM dual mode dielectric resonator is provided in an electrically conductive case, wherein the TM dual mode dielectric resonator comprises first and second dielectric resonators integrally formed so as to be perpendicular to each other, and coupling grooves for coupling an operation mode of the first dielectric resonator with an operation mode of the second dielectric resonator are formed in the TM dual mode dielectric resonator. Cross-sectional areas or sizes such as thickness, widths or the like, of the first and second dielectric resonators are set so as to be different from each other. Alternatively, a hole for adjusting the resonance frequency is formed at an end of one of the first and second dielectric resonators so as to penetrate the same.

Abstract: Dual-mode cavity of waveguide bandpass filters, which allow the realization of narrow-band filters with very limited transition band and extremely low losses, without tuning or coupling screws or smooth edges. The dual mode cavity is composed of three coaxial sections of waveguide arranged in cascade and provided with irises, of which the two end sections are suited to support two modes with orthogonal polarizations and the intermediate section, consisting of a rectangular waveguide, has its side tilted with respect to the plane on which the irises lie. The whole filter composed of these cavities can be entirely designed by means of a computer and requires no tuning operation.

Abstract: A multiple output filter coupler for providing plural RF output signals from a single RF input signal may include an RF waveguide filter for receiving an RF input signal at one end thereof and for filtering the received RF input signal along its length, and plural connectors attached to the waveguide filter's end cavity for providing plural filtered RF output signals. Tuners attached to the waveguide filter proximate the connectors may be used to vary the relative signal strengths of the filtered RF output signals. The filter coupler's output and input may be interchanged to provide a single output from multiple inputs.

Abstract: The present invention is a passband-type waveguide filter in which a periodic distortion is employed which has a sinusoidal, or alternately configured, distortion, which changes phase at a point along the periodic distortion. The passband filter comprises essentially any waveguide, designed as a waveguide, with a periodic distortion added to at least one of the sides of the waveguide. The waveguide can be a rectangular cross section metallic microwave type, cylindrical, elliptical, or microstrip. The waveguide may be optical, a SAW type waveguide or any waveguide of the prior art. In a preferred embodiment a waveguide structure supports propagation of a wave along the waveguide, the waveguide structure containing a boundary and the waveguide structure containing a filter portion having a portion of said boundary with a sinusoidal distortion following:f(z)=1+A sin (k.sub.w z) for 0<=z<=L/2f(z)=1-A sin (k.sub.

Abstract: A branching filter for a transmitter-receiver which is used in a microwave band comprising an orthogonal-mode transducer (waveguide branching filter), a reception filter comprising a band-eliminating filter 4 which is connected to the extension of the center axis of the waveguide of the orthogonal-mode transducer, and a transmission filter comprising a high pass filter containing a cut off waveguide which is directly and orthogonally connected to the orthogonal-mode transducer. The parts of the branching filter for the transmitter-receiver are integrally manufactured as one body by a lost wax process. Therefore, the branching filter for the transmitter-receiver can be manufactured as a compact-size single body having no patch or linking portion.

Abstract: A dual-mode dielectric-resonator-loaded cavity filter comprises a generally cylindrical cavity, at least two longitudinally-spaced dielectric resonator elements coaxially aligned within the cavity, and at least one coupling obstacle disposed between the resonators and extending a distance from the cavity wall. The coupling obstacles are preferably conductive and are electrically connected to the cavity wall. However, the obstacles may be constructed of a dielectric material in some applications. Each obstacle may be aligned with one of the reference planes corresponding to a resonant mode of the resonators to effectively control or reduce the coupling between the parallel resonant modes of adjacent resonators. The reduction in coupling between resonant modes of adjacent resonators allows large coupling differentials to be produced, allowing a filter designer to implement a wide variety of high-performance filters without expensive irises.

Abstract: A high Q microwave filter is disclosed. Coupling bar structures are included in a cylindrical resonator, extending substantially the entire length of the resonator for coupling orthogonal modes. The coupling bars have a lower profile than conventional tuning screws. The symmetry of the filter structure is improved over the prior art coupling devices which relied entirely on tuning screws for coupling E fields of one mode to the other mode. The coupling bar structure has a lower profile penetrating less into the supported E fields while obtaining the desired coupling. Increased bandwidth may be obtained at improved symmetries over the prior art devices. Fine tuning may be provided by inserting tuning screws into the cylindrical cavity. The tuning screws require less penetration as substantially most of the coupling occurs by virtue of the coupling bars.

Abstract: In order to improve filter loss of a waveguide filter having coaxial/waveguide mode conversion parts at its ends, conductor posts bridging a space between two long sides of the waveguide are provided between the parts and the ends. The conductor posts have sufficient thickness and remain close enough to each other and to short ends of the waveguide that a partition plane including axes of the conductor posts can be regarded as an imaginary short plane. The conductor posts are located so that the partition plane is positioned at a distance .lambda./4.times.n (n=1, 3, 5 . . . ) from the coaxial/waveguide mode conversion part.

Abstract: A high isolation microwave module includes a housing floor with mounting surfaces for placing microwave components and housing walls ending in housing wall ends coupled to and projecting from the housing floor. A lid including a lid plate and lid walls ending in lid wall ends projects from the lid plate. The lid walls extend toward the housing floor and the plurality of housing walls extend toward the lid plate but neither the lid wall ends nor the housing wall ends are coupled to the housing floor or lid plate, respectively. A plurality of cavities exist between the adjacent lid walls between the housing and the lid plate and a plurality of irises exist between immediately adjacent housing walls and corresponding lid walls. The irises and cavities act as a multi-section high pass filter to provide attenuation to a microwave signal passing through the module.

Abstract: Waveguide filters having a laminated dielectric structure for resonating at a predetermined frequency and having a series of longitudinally spaced resonators. A selected plural number of individual layers of high dielectric low temperature co-fired ceramic are laminated into a monolithic structure and then plated with a conductive material. Each of the individual layers is dimensioned and the number of layers is selected so that the unit resonates at the predetermined frequency. A waveguide filter is also described where a select plural number of contiguous layers of low temperature co-fired ceramic are laminated and plated with a conductive material. A series of vertically placed vias are positioned so as to form a perimeter of a waveguide filter. A plurality of individual layers of low temperature co-fired ceramic are laminated to the monolithic structure to form a laminated unit so that electrical components and the waveguide filter can be integrated into a single package.

Abstract: A two port dual bandpass microwave filter consisting of "n" resonant cavities. Each cavity resonates in two independent modes at displaced frequencies so that the filter has two passbands in a desired frequency band. By orienting an incoming waveguide at an angle with respect to the filter, both TE and TM modes can be excited to produce two separate passbands. The passbands may have either equal or unequal characteristics. Fine tuning of the TE and TM modes is accomplished using tuning plungers or tuning screws. The dual bandpass response of the new filter is achieved by utilizing the TE.sub.1,1,1 and TM.sub.0,1,0 modes in right circular cylindrical cavities, or equivalent modes in rectangular, or other cavities. These modes are orthogonal so they do not couple to each other. The cavity loaded Qs are independently adjustable, so the two passbands can have the same or different bandwidths, the same or different amplitude ripples and the same or different phase responses.

Abstract: A device for the filtering of electromagnetic waves propagating in a main rotational symmetrical waveguide element comprising at least one filtering section constituted of a rectangular waveguide section inserted in being spliced into the main waveguide element, each transition between said main waveguide element and each of said filtering sections being made by metal walls which are substantially perpendicular to said axis of symmetry, the number and the geometrical and dimensional characteristics of the filtering sections being chosen so as to constitute a filter with a pre-determined filtering profile. The device can be applied especially in dual band filtering, for example for the making of dual band or bi-polarization duplexers.

Abstract: A precision, waveguide-configured, bandstop filter comprises a substrate formed of a conductive material capable of being die cast. To facilitate manufacture and assembly, the substrate is preferably formed as a pair of symmetrically shaped substrate halves which, when mated together, define an interior filter structure that performs the required bandstop filter function. Each substrate half is configured to have a generally longitudinal slot that extends from a planar mating surface and effectively forms one half of an interior longitudinal waveguide section through the filter. Transverse to and located at spaced apart locations along the longitudinal slot are a plurality of channels, which define parallel conductive surface webs that extend from opposite sidewalls of the longitudinal slot. The channels serve as distributed, diametrically opposed pairs of lumped parameter tuning elements of the bandstop filter. A first end of each web forms a portion of a conductive sidewall of the longitudinal slot.

Abstract: The present invention is directed to reducing the number of components required to minimize intermodulation distortion within the wide transmission frequency band used by a satellite communications repeater system. In particular, at least two TM.sub.010 mode cavity is cascaded to a plurality of TE.sub.113 mode cavities to form a narrow band-pass, wide band-stop filter for receiving and outputting channel signals to the multiplexer manifold of a satellite repeater. The filter thus constructed realizes the narrow band-pass response required in microwave communications, while eliminating the spurious resonance frequencies normally eliminated by additional filter components. In this manner, the size and weight considerations of the satellite system are improved without loss in performance.

Abstract: In a branching filter, a transmit filter (14) is divided into first and second transmit filter parts (17, 18). A waveguide branching filter (15) is divided into first and second branching filter parts (19, 20). A receive filter (16) is divided into first and second receive filter parts (21, 22). The first transmit filter part is assembled with the second branching filter part and the second receive filter part. The second branching filter part is assembled with the second receive filter part. The first branching filter part is assembled with the first receive filter part. Alternative assembly is possible. As a further alternative, an installation hole may be formed in the branching filter for removable installation of a cable and be covered with a cover with a packing interposed for hermetic seal and waterproofing.

Abstract: A switchable dual mode directional filter system includes two identical filters coupled to input and output waveguides at the same plane in phase quadrature. Each waveguide has two ports through which the signal enters and exists. One of the filters has a switching device incorporated therein for selecting the desired output port. One embodiment of the switching device includes a pair of coupling members that extend radially inward within the cavity of the filter toward a central axis. These coupling members define two coupling positions for the system. Solenoids move the two coupling members into and out of the cavity of the filters. Only one coupling member is used at a given time. This switching device is designed to change the polarity of one of the components of the signal wave to change its wave characteristics in the output waveguide. As a result, the desired port of the output waveguide can be selected easily.

Abstract: A magnetostatic wave filter comprises a waveguide having a cut-off frequency region. In this waveguide, a YIG thin film is installed as a ferrimagnetic base material. Also, the cut-off frequency region of this waveguide comprises an attenuation band of the magnetostatic wave filter. Electromagnetic wave in the attenuation band of the magnetostatic wave filter is attenuated by this waveguide.

Abstract: A waveguide low pass filter is composed of an assembly of an outer waveguide, an inner waveguide shorter in length than the outer waveguide, and a printed circuit filter substrate. The outer and inner waveguides have split block constructions. The inner waveguide is mounted within the outer waveguide so as to form a constriction within the outer waveguide limiting propagation of energy within the outer waveguide to the fundamental TE.sub.10 waveguide mode. The printed circuit filter substrate is mounted to extend longitudinally between the assembled split halves of the respective outer and inner waveguides, and is constructed of a substantially planar dielectric substrate element and upper and lower conductive plate elements on the substrate and lying in the plane thereof. The conductive plate elements define a tapered dual ridge transformer section. The lower plate element has longitudinally spaced vertical slots formed therein defining an open stub slotted filter array.

Abstract: A low loss high-pass microwave filter for microstrip circuits comprises a single-ridge waveguide which is attached to a microstrip circuit in a manner to establish a cutoff frequency for the circuit. The single-ridge waveguide has a top wall and sidewalls with a ridge projecting centrally from the top wall into the waveguide. The waveguide is associated with the microstrip circuit such that the sidewalls of the waveguide extend through a dielectric substrate of the circuit parallel to and on opposite sides of a microstrip line of the circuit and are connected electrically and physically to the ground plane, which forms a bottom wall for the waveguide. The ridge of the waveguide has a width which is equal to or narrower than the microstrip line and is aligned with the microstrip line.