Abstract: A wideband enhancement sum mixer is shown to comprise a pair of matched GaAs diodes operative with a printed circuit wherein a portion of at least the sum signal, i.e., the sum of a radio frequency signal and a local oscillator signal, is caused to be mixed with the second harmonic of the local oscillator signal to produce an intermediate frequency signal in phase with the intermediate frequency signal resulting from mixing of the radio frequency signal and the local oscillator signal.

Abstract: An image suppression mixer of the waveguide type is disclosed which includes a waveguide signal input terminal at one end of a waveguide, a local oscillation input terminal at the other end of the waveguide, a mixer diode inserted within the waveguide and an IF signal output terminal connected to the mixer diode. At least the width of the waveguide on the side of the waveguide signal input terminal is selected to be a cutoff dimension for the image frequencies f.sub.m and the local oscillation frequency f.sub.1 the waveguide signal frequencies f.sub.2, the local oscillation frequency f.sub.1 and the image frequencies f.sub.m are correlated as f.sub.m <f.sub.1 <f.sub.s.

Abstract: Multipliers for high frequencies having an input and an output. The input is connected via a terminating impedance to the input of a short-circuited transmission line having a length .lambda./4, where .lambda. is the wavelength of the desired output frequency. The input of the short-circuited transmission line is connected to a point of constant potential via a first impedance and also to the output via a second impedance which is much higher than the terminating impedance. The output is connected to the input of an open-ended transmission line having a length .lambda./2.

Abstract: A radio-frequency mixer and a local oscillator integrated into a single housing, and including a Gunn-type oscillator coupled to the mixer by a section of microstrip transmission line and a section of suspended stripline. A broadside coupler in the suspended stripline provides dc and intermediate-frequency isolation for the mixer, and a block of dielectric material on the microstrip provides improved temperature compensation for the diode oscillator. The entire compact assembly has good conversion loss performance over a relatively wide frequency band, and is relatively insensitive to temperature changes.

Abstract: A hybrid ring mixer includes an annular conducting ring on a gallium arsenide substrate coated on the bottom with a conducting layer to comprise a strip transmission line. Three conductors spaced by 120.degree. extend radially outward from the annular ring to define local oscillator, signal input and i-f ports, respectively. A pair of conductors spaced by substantially 120.degree. extend radially inward to comprise diode ports. A conducting surface inside the annular ring is grounded and has circular sectors of different radius bounded by radii extending from the center of the ring and bisecting the signal and local oscillator ports, respectively. The sector of larger radius is located in the 120.degree. sector between the signal and local oscillator ports. Mesa diodes are connected between each of the diode ports and the sector of smaller radius.

Abstract: A doubly balanced mixer comprising a ring modulator each leg of which is formed by the series connection of a high speed switching diode and one or more diodes with low intrinsic resistance and with high accumulated charges, preferably of the "varactor" or "PIN" type.

Abstract: A mixer including a plurality of mixer diodes arranged at a junction formed by first, second and third waveguides. The first waveguide is a slot transmission line including spaced-apart conductive layers on each of the opposite sides of a dielectric substrate. The second waveguide is a coplanar transmission line including spaced-apart conductive layers and a central conductive layer on each side of the substrate. The third waveguide is a parallel plate transmission line including extended portions of the central conductive layers, which extend toward the slot in the first waveguide. The diodes electrically connect the extended portion of the central conductive layers to the spaced-apart conductive layers of the first waveguide.

Abstract: A single balanced planar mixer is disclosed suitable for use in the reception of electromagnetic waves of extremely high frequencies including millimeter waves. The mixer may be combined with an antenna, the combination being particularly suitable for use in antenna arrays. The arrangement is planar combining coplanar strip, coplanar line, and microstrip transmission lines formed on an insulating substrate in a single balanced arrangement providing isolation between the antenna port on the one hand and the local oscillator and IF ports on the other hand. Additional filters suitable for fabrication on a substrate are employed to provide isolation between the local oscillator and intermediate frequency ports. At lower frequencies, the arrangement may be in a hybrid format using an insulating substrate and discrete diodes. At higher frequencies the arrangement may be monolithically integrated using a gallium arsenide substrate with integrated diodes.

Abstract: An apparatus and method is disclosed for a balanced mixer having a fifth port capable of removing the intermediate frequency and the upper sideband frequency while acting as an open circuit to the RF and local oscillator input signals. The upper sideband signal is then dissipated in a distributed load designed so as not to reflect the upper sideband signal back into the transmission ring. Thus, a balanced mixer is disclosed that provides IF signals and removes other unwanted signals without corrupting later signals.

Abstract: The output of a doubly-balanced mixer of a television tuner is terminated by a network which exhibits the characteristic impedance of the mixer for both the sum and difference frequency components. The difference frequency component termination simply consists of an inductor and a capacitor connected as a series-tuned circuit and a resistive element connected in series between the output of the mixer and signal ground. The inductor and capacitor are selected resonate at a frequency in the passband of the IF section and the resistive element is selected to exhibit the characteristic impedance of the mixer. The sum frequency component termination simply consists of a capacitor and a resistive element connected in series between the output of the mixer and signal ground. The capacitor is selected to exhibit negligible impedance just below the lowest frequency of the sum frequency component and the resistive element is selected to exhibit the characteristic impedance of the mixer.

Abstract: In a microwave mixer circuit, two diodes connected in series are formed in a semi-insulating semiconductor substrate. A power distributing circuit is connected across the series circuit of the diodes. One of the connecting points is connected to a first signal terminal. A line connecting the two diodes in series is connected to the second signal input terminal and through a low-pass filter element to an intermediate frequency output terminal.

Abstract: A diode mixer arrangement including a mixer stage connected for receiving a signal having a frequency to be converted and an oscillator signal having one of a plurality of preselectable oscillator frequencies. The mixer stage includes diodes arranged to be biased by a predetermined direct control voltage for the compensation of parasitic influences. A voltage branch is connected to the mixer stage for producing the predetermined direct control voltage. The voltage branch includes a memory device for storing a plurality of data signals each of which represents a predetermined direct control voltage corresponding to a respective one of the plurality of preselectable oscillator frequencies. The memory device has an input for receiving an input signal which represents the preselectable oscillator frequency of the oscillator signal received by the mixer stage and an output for reading out the corresponding data signal which is used by the voltage branch to generate the predetermined direct control voltage.

Abstract: A hermetically sealed quasi-planar integrated circuit suitable for millimeter-wave transmission. The circuit is enclosed within a module having a metal frame soldered to a quartz window. Active elements, such as beam-lead diodes, are mounted on a conductive layer housed within the frame. The assembly is evacuated and may be filled with an inert gas to avoid condensation in humid operating conditions. The invention is particularly adaptable to use in a cross-bar signal mixer at frequencies up to 140 GHz. The structure is adaptable to cooling to reduce circuit losses and improve performance and operating efficiency. Resonant cavities are provided to permit tuning the mixer to fixed frequencies.

Abstract: A dual Gunn self-oscillating mixer is shown which can mix signals in the range substantially without introducing any noise and with high input signal power handling capacity and with higher output mixed signal power than conventional, owing to boosted power from more than one microwave cavity. The device is comprised of two cavities and connected by a 180.degree. phase shift coax line for injection locking, or a cavity wall hole in yet another embodiment. The device handles larger power levels without burning out as compared to conventional type mixer devices such as Schottky barrier diodes having nearly 30 times the burnout susceptibility.

Abstract: In a microwave device, for example a microwave local oscillator with a harmonic mixer for feedback control, problems of coupling the mixer circuit to the R.F. cavity are overcome by providing a d.c. blocking capacitor of the mixer on a planar surface of a support extending across an aperture in one wall of the cavity. In preferred embodiments the capacitor is a planar device formed by a plurality of interdigitated fingers. These fingers are oriented to couple magnetically with the R.F. energy at the aperture in the cavity. The support conveniently comprises a printed circuit board having a ground plane on the same surface as the capacitor, which is located in a small opening in the ground plane. A second ground plane is provided on the opposite side of the printed circuit board, overlying the opening. The two ground planes are interconnected by plate-through-holes.

Abstract: A multifunction ultra-high frequency circuit and bidirectional transmission means using such a circuit. The circuit according to the invention comprises a directional coupler, two diodes, a transistor and an access connected to the diodes. The state of the transistor defines several functions of the circuit: modulation, mixing and transmission-reception separation. Application to half-duplex transmission.

Abstract: A single planar doped barrier diode is grown by the selective deposition of gallium arsenide using molecular beam epitaxy (MBE) in the center of a gallium arsenide dielectric waveguide member mounted on a ground plane. The waveguide member includes two portions which extend in opposite directions and terminating in respective metal to dielectric waveguide transition sections which are coupled to an RF input signal and local oscillator signal, respectively. The planar doped barrier diode operates as an intrinsic subharmonic mixer and accordingly the local oscillator signal has frequency of one half the input signal frequency. An IF output signal is coupled from the mixer diode to a microstrip transmission line formed on an insulating layer fabricated on the ground plane. Dielectric waveguide isolators are additionally included on the dielectric waveguide segments to mutually isolate the input signal and local oscillator signal.

Abstract: An R.F. circuit with at least one R.F. transmission line including a strip conductor (15) and a ground plane (13) on an insulating substrate (3) and having two diodes (24, 25) respectively D.C.-connected to two portions (38,39) of the ground plane (13). The two portions are mutually D.C.-isolated by a slot (37) to enable the diodes (24, 25) to be biased. The substrate (3) is mounted in a housing (1, 2) of conductive material, and the two portions (38, 39) of the ground plane (13) are mutually R.F.-coupled via the conductive material. One of the portions (39) is electrically-connected to an adjacent housing member (2) and the other portion (38) is separated therefrom by a thin insulating layer. The slot (37) inhibits coupling of R.F. energy out of the circuit into the slot (37), suitably being very narrow, e.g. 20 .mu.m, so as to form a further transmission line with a very low characteristic impedance and also to have a high attenuation along its length for operation at mm-wavelengths.

Abstract: A monolithic mixer which is impedance matched to a fundamental waveguide, utilizes a slot coupler and a coplanar transmission line to apply an RF and local oscillator signal to a Schotty-barrier diode. The dielectric substrate is utilized to create a dielectric surface wave resonance which is utilized by centering a slot coupler with respect thereto, to provide a reactive image termination at the upper sideband and thereby enhance single and double sideband mixer operation. The IF signal which is available at the output of the Schottky-barrier diode is filtered by means of an RF bypass capacitor that is located on the dielectric substrate surface.

Abstract: A magnetically tuned band reject filter for millimeter wave frequencies crising a barium ferrite sphere embedded in the upper surface of a semi-insulating gallium arsenide waveguide transmission line element located on a conductive ground plane and forming thereby an image guide. A pair of high energy rare earth permanent magnets are located on the upper and lower surfaces of the waveguide element at the location of the ferrite sphere with a single tuning coil surrounding both the magnets and the waveguide and operates to bias the ferrite sphere for selective absorption of signals propagating along the transmission line. With the magnetically tuned ferrite sphere located therebetween, both an input signal and a local oscillator signal, for example, are coupled to one end of the waveguide element while receiving electronics apparatus, such as a Schottky barrier diode mixer, is located at the other end of the waveguide element.

Abstract: A signal modifying device comprises an elongate section of waveguide and a non-linear circuit element. A lateral through-hole is formed in a wall of the waveguide, and a rod-like conductive member is fitted in the hole and has one end presented towards the opposite wall region of the waveguide. The non-linear circuit element is secured to the rod-like member with one electrode connected in electrically conductive manner to the rod-like member and with a beam-like lead (which is connected to another electrode of the circuit element) extending towards the opposite wall region of the waveguide.

Abstract: A mixer circuit in which resonance characteristics of a resonance circuit coupled to the RF input terminal are prevented from entering the mixer circuit, and in which negative resistance characteristics in the local oscillator circuit are prevented from causing spurious oscillations in the mixer circuit. The mixer circuit comprises a main strip line connecting an RF input terminal to an output terminal through a frequency mixing diode and a low pass filter. The IF signal is short circuited where the mixer diode is connected to the main strip line, by a high frequency short-circuiting technique. An IF interrupt circuit is provided in the main strip line near the RF input. A resistor ended low pass filter is connected between the RF terminal and the IF interruption circuit. The local oscillator includes a strip line having a length equal to one quarter of the wavelength of the spurious oscillation which is to be prevented.

Abstract: A DC current injectable double balanced diode ring mixer circuit for radio frequency (RF) application. The diode ring includes eight diode elements and defines eight terminals including four symmetrical DC injection ports in conjugate pairs interleaved with four symmetrical RF inputs for phase and anti-phase application.

Abstract: A microwave integrated circuit frequency converter includes a first filter (30) for a signal frequency and a second filter (32) for a local oscillator frequency connected at one terminal thereof with one terminal of the signal frequency filter (30) by a line (38), (40) having a predetermined electrical length. A parallel stub line (42) is short-circuited at one end thereof. A diode (34) is connected at its one end to a third filter (36) which is adapted to reflect the signal and local oscillator frequencies while passing an intermediate frequency. The diode (34) is connected at the other end to a line (41).

Abstract: A microwave oscillator and a combination microwave oscillator/single balanced mixer for a satellite television receiver includes a cylindrical dielectric resonator located on one side of a ground plane formed by a conductive foil on a substrate with microstrip transmission lines formed by foil patterns on the opposite side of said substrate. A gallium arsenide FET is disposed in a hole through said substrate with its source electrode connected to the ground plane and its drain and gate electrodes coupled to first and second transmission line strips, portions of which are following the contours of said dielectric resonator. Two sets of coupling slots are formed in the ground plane for permitting magnetic coupling between the dielectric resonator and the opposite transmission line strips. In one embodiment an additional coupling slot in the ground plane couples the dielectric resonator to an output transmission line strip.

Abstract: An integrated planar antenna-mixer device for microwave reception utilizes a slot-ring antenna and a diode quad connected thereto. The device comprises a planar metallic sheet backed on one side by a dielectric layer. A circular ring pattern is cut from the metallic sheet forming a slot ring antenna with a central disc and a surrounding ground plane. Diodes of a diode quad are connected between the central disc and the ground plane with adjacent diodes being separated by 90.degree.. The incoming microwave signal is directed perpendicular to the device plane and polarized in a direction orthogonal to a local oscillator signal similarly directed. Operation is quasi-optical without waveguides.

Abstract: A frequency conversion unit comprising a local oscillator, first and second mixers, first and second hybrid circuits. The mixers receive, via the first hybrid circuit, local oscillation outputs from the local oscillator, and the second hybrid circuit receives outputs from the first and second mixers, producing a frequency conversion output signal therefrom. Intermediate frequency signals used in the first and second mixers are .pi. radians out of phase with each other. The first hybrid circuit produces outputs for the first and second mixers having a predetermined phase difference of .phi..sub.1 therebetween. The second hybrid circuit receives outputs from the first and second mixers and combines them after making a phase difference of (.pi.-.phi..sub.1) therebetween.

Abstract: A millimeter-wave, planar, balanced mixer having optical means for coupling radio frequency waves to the mixer circuit. The optical coupling means may comprise a dielectric lens and particularly a spherical dielectric lens. The spherical lens not only provides a gain for the radio frequency energy but overcomes the severe tolerance requirements and size restrictions encountered in fabrication of conventional waveguides for millimeter waves in the range of 100 to 300 GHz.

Abstract: A biconical antenna, the halves of which are connected together at the apex by a pair anti-parallel diodes through a pair of parallel conductive whiskers or wires. A pair of quasi-optical lenses focuses energy from a local oscillator and from a submillimeter radio source, respectively, onto the diode pair in the end-fire and broadside direction, respectively. The diode pair spacing is equal to the half wavelength of the local oscillator energy. The local oscillator energy is common mode rejected and causes the incoming radio energy to be sampled by forward biasing the anti-parallel diode pair in synchronism with each zero crossing of the local oscillator energy. Accordingly, the local oscillator energy and noise virtually do not affect the current flow between the halves of the biconical antenna. The current flow represents an intermediate frequency signal corresponding to the difference in frequency between the incoming radio signal frequency and the local oscillator frequency.

Abstract: In an RF receiver, the unsymmetric RF input to a single balanced mixer is provided from the preceding portion of the receiver by means of a hybrid coupler to provide DC decoupling and impedance transformation at the RF and image frequencies. The hybrid coupler includes first and second microstrip conductors on the first side of a circuit board, each respectively coupled to the preceding portion of the receiver such as to a preamplifier and to the mixer and mutually electromagnetically coupled. On a second side of the circuit board is located a slot etched in the circuit board's conductive ground plane providing the single balanced mixer with a symmetric oscillator frequency source. The ground plane in which the slot is located forms one wall of a cavity in which a dielectric resonator is contained which, coupled to either end of the slot and in combination with an active device, forms the oscillator frequency source.

Abstract: In a mixer using a planar circuit such as a strip line or a microstrip line etc., an IF signal interruption circuit which passes an RF signal but exhibits an open-circuit impedance against an IF signal is provided in shunt with a main line on which the RF signal propagates toward a mixer diode, and a low-pass filter is connected in the vicinity of the IF signal interruption circuit in order to short-circuit a mount point of the diode for the IF signal by high frequency short-circuiting technique wherein an open-ended quarter-wavelength transmission line or a short-circuited half-wavelength transmission line is used, whereby low noise performance can be obtained over a wide frequency band even under such an operating condition that the IF signal is in the GHz band.

Abstract: A stripline tuning fork microwave balanced mixer circuit which includes two diodes (21, 22) and a differential transformer (61) whereby matching is accomplished in the differential transformer (61) and in the circuit arrangement between the differential amplifier and the diodes (21, 22) for matching the resistance to the input terminals (1, 2) and a transforming circuit (24, 25, 26) which suppresses the frequency range of the input signals following the diodes and has simultaneous high frequency blocking for matching to the intermediate frequency signal output at terminal (3). This latter circuit can be utilized so that it functions as a blocker for the sum frequencies of the two input signals and the balanced push-pull mixer circuit of the invention can be used in sensitive receivers used in the microwave range.

Abstract: The present invention relates to a mixer for use at high microwave frequencies (typically 21.8.times.23.2 GHz) in a low cost communications application. The invention utilizes low cost microwave components, including a low cost compartmented waveguide, shared by the signal and local oscillator and extensive microstrip circuitry. The provision of a pair of novel 1/4 wave impedance transformers coupled into the waveguide compartments provides efficient antenna and local oscillator input filtering, and efficient coupling from the waveguide sections to the microstrip circuitry. The mixer operation is carried out in the microstrip circuitry, which contains a hybrid coupler, a balanced diode detector, and the required mixer output filter. The arrangement is of low cost, and provides a low noise figure (7 db including the preamplifier), good band selectivity (15 db return loss over the communications band), and low local oscillator radiation.

Abstract: A millimeter-wave stripline planar mixer to provide a means for mixing a local oscillator signal with a radio frequency signal to produce an intermediate frequency signal, the mixer utilizing beam lead schottky-barrier diodes in a balanced configuration.

Abstract: Microwave circuit layout structure is disclosed for a diode mixer frequency converter. Each mixer port is provided by balun circuitry, and the diodes are isolated from, and on the opposite side of the substrate from, the primary circuits of the baluns. Single and double sideband versions are disclosed, including various combinations of dual and single baluns and porting structure.

Abstract: A subharmonic mixer, whose local oscillator is at half the frequency of that of the signal to be received, comprising a detector and a local oscillator positioned in a single waveguide (301). The mixer comprises a first module (51) serving as the local oscillator and incorporating an oscillation diode surrounded by dielectric material and connected to a wide metal coating, as well as a second module (52) incorporating an antiparallel connection of two Schottky diodes and which is identical to the first module. The metal coatings of these two modules are in contact with metallized areas (53, 54) of a double-faced printed circuit (15) serving for the polarization of one module and for the signal output of the other.

Abstract: Microwave circuit layout structure is disclosed for a diode mixer frequency converter. The circuit layout structure is compact and symmetric, and enables coplanar diode lead connection.

Abstract: Microwave circuit layout structure is disclosed for a diode quad mixer frequency converter with separate, isolated sections, each supplied by a respective half of dual balun port structure. The circuit layout structure is compact and symmetric, and enables coplanar diode connection.

Abstract: A simplified, compact, flat microwave frequency converter assembly utilizes a flat quad diode bridge, and has two pairs of opposed flat conductors, each with a respective one of the opposed conductors on a respective side of a flat dielectric substrate . Each of the pair extends orthogonally from their intersection at the bridge. The bridge is connected at opposite corners thereof to adjacent ends of the conductors at the intersection on a first side of the substrate. These first-side conductors are in electrical continuity with a conductive layer extending about the periphery of the substrate on the first side thereof. This layer is, in turn, in contact with a conductive carrier plate by means of which the layer is grounded. On the second side of the substrate, each of the pair of capacitors affixed to the substrate is connected between respective opposite corners of the bridge, and the adjacent ends of the conductors of one of said pairs.

Abstract: An up converter having on the one hand an ultrahigh-frequency ring receiving one of the waves to be mixed and on the other hand a transformer receiving the other wave to be mixed whose frequency is in the radio-electric range. The transformer is connected to the ring through a bridge of mixer diodes which are placed with this transformer and a capacitor for tuning this latter inside the ring. The resulting wave exits from the ring through a waveguide having two traps tuned to the frequency of the wave applied to the ring.

Abstract: A mixer comprising two microstrip plates, each having an earth plane, a dielectric layer and an etched layer. One of the etched layers carries the mixer ring and input guides. The outer etched layer carries the output guide and the tuning members. The plate are joined by their earth planes and the mixer diodes are placed in the holes connecting the two etched faces.

Abstract: A low frequency diode mixer is provided in combination with simple, compact transformer circuitry. A four diode mixer interconnects three dual transformers. The mixer has a pair of separate, isolated two diode sections commonly servicing the first transformer and separately servicing the other two transformers.

Abstract: A balun coupled microwave frequency converter is provided by a mixer using a single diode pair with one port balanced and the other port unbalanced. The balanced port is provided by first and second coplanar conductors extending toward a common area and juxtaposed in spaced parallel relation with a transmission line interacting therewith to couple a field balanced between the first and second conductors across the common area. The unbalanced port to the mixer is provided by a third conductor. The diode pair is connected in series between the first and second conductors, and a point between the diodes is connected to the third conductor. One implementation is an up converter with an LO and an IF signal applied on the third conductor and input to the mixer to generate an RF signal between the first and second conductors and hence an induced output RF signal on the transmission line.

Abstract: A frequency converter has first, second and third terminals which receive a first signal having a first frequency band, a local oscillation signal, and a second signal having a second frequency band. The first signal and the local oscillation signal are mixed to generate the second signal. A first branching circuit is connected between the second terminal and the frequency mixer, for branching part of the local oscillation signal. A first part of the branched local oscillation signal, which is supplied from the first branching circuit, and a first leaked local oscillation signal are applied from the frequency mixer to the first terminal. The phase and amplitude of the first branched local oscillation signal are adjusted so that the first branched local oscillation signal and the first leaked local oscillation signal have equal amplitude and are reversed in phase to cancel each other.

Abstract: An improved broadband mixer includes a first balun (11) with a first signal port (12), a second balun (14) with a second signal port (15), a third balun (17) with a third signal port (18), and a frequency converter (19) coupled between the first, second, and baluns. The first balun means, which preferably receives an RF signal via said first signal port, includes two juxtaposed ground plane baluns 31 and 32 each having opposed, spaced, strip conductors in different planes. The second balun, which preferably receives an LO signal via the second signal port, has a coplanar balun (44) including three strip conductors in the same plane which in turn connects to two juxtaposed ground plane baluns (45 and 46) each having opposed, parallel spaced, strip conductors.

Abstract: The millimeter and submillimeter wavelength oscillator includes a Gunn diode coupled to a hole in a ferrite image waveguide in such a way that a portion of the waveguide acts as a resonant cavity, and oscillation results. A coil surrounding the portion of the waveguide has a variable dc current applied to it to variably magnetize the waveguide and hence correspondingly vary the oscillator frequency. By applying an RF signal to the Gunn diode, the oscillator frequency can be mixed with the RF to yield heterodyne or intermediate frequencies.

Abstract: In a microwave circuit for a parametric upper sideband down converter with real image frequency termination conductance, including a pump circuit supplying a pump signal, a parallel circuit at its input, an intermediate frequency circuit at its output, and a reactance diode coupling the parallel circuit and intermediate frequency circuit together, the parallel circuit is tuned approximately to the frequency of the pump signal; the intermediate frequency circuit is composed of a .pi.

Abstract: The invention aims at obtaining an intermediate beat frequency from two millimeter wave frequencies by attenuating as much as possible the amplitude variations of the frequency coming from the local oscillator.The mixer of the invention comprises two modules each containing a diode, one electrode of which is grounded to a conducting support. The modules are face to face. The diodes detect the electric field of the wave of the signal to be processed reigning in a cavity, and through conducting strips serving as outputs for the mixer and extending into a cavity where the electric field radiated by the local oscillator reigns, each module also detects a part of this electric field. The output terminals of the intermediate frequency are connected to an operational amplifier.

Abstract: A double-balanced mixer circuit includes a diode ring, wherein each side of the diode ring is provided with a stripline to bypass high frequency signals.

Abstract: First and second directional couplers each having a primary arm, a through arm and two secondary arms with a resonant circuit constructed to include the two secondary arms of each directional coupler. The directional filter forms a four port device with signals of a first frequency being applied to the first port and coupled to the fourth port by the resonant circuit, and signals applied to the third port being conveyed directly to the first port. Signals other than those at the first frequency are not coupled between the first and fourth ports.