Abstract: A microwave applicator system exposing a material flowing through multiple applicator stages to a different radial heating pattern in each stage for uniform heating. A two-stage applicator system has a pair of back-to-back applicators, each having offset, outwardly jutting walls on opposite sides of a material flow path through a microwave exposure region. The offset, cylindrical juts formed in the wide walls of the generally rectangular waveguide cause hot spots to occur in material flowing through and between the narrow walls of the waveguide at opposite radial positions on a radial line oblique to the longitudinal direction of the waveguide. Uniform product heating can be achieved by directing a material sequentially through these two applicators in opposite directions. A cascaded applicator in which each wide wall has a pair of outward juts offset from each other and from the pair of juts on the other side wall may be used.

Abstract: The present invention provides a surface wave excitation plasma generator in which surface wave excitation plasma is efficiently generated. A surface wave excitation plasma generator including an annular waveguide and a dielectric tube is provided. The annular waveguide 2 includes an inlet 2a for introducing a microwave M, an end plate 2b for reflecting the microwave M introduced and propagating within the waveguide, and a bottom plate 2c on which slot antennas 2d are formed at a predetermined interval. When the wavelength of the microwave M in the waveguide is ?g, the length from position b through positions c, d, e to position f on the bottom plate 2c, i.e. the circumferential length (?×D1) of the annular waveguide, is set as 2 ?g, and the positions b, c, d, e, f are spaced apart at an interval of ?g/2. Since the slot antennas 2d are arranged at two positions c and e, the interval between these two slot antennas 2d is equal to the wavelength ?g in the waveguide.

Abstract: The present invention provides methods for decomposing and extracting compositions for the recovery of petroleum-based materials from composites comprising those petroleum-based materials, comprising subjecting the compositions and/or composites to microwave radiation, wherein the microwave radiation is in the range of from about 4 GHz to about 18 GHz. The present invention also provides for products produced by the methods of the present invention and for apparatuses used to perform the methods of the present invention.

Abstract: A microwave power supply includes a magnetron, a waveguide configured to carry microwave power from the magnetron to a selected load, and an adjustable impedance element connected to the waveguide at a location upstream from the magnetron. The power supply may further include provision for varying the filament voltage to the magnetron tube. In the associated method, the adjustable upstream impedance and the adjustable filament voltage may be combined (and may be adjusted iteratively) to achieve high Q output. The load may be an applicator cavity for processing selected materials. The invention is particularly suitable for high Q cavities, such as single mode cavities, where it is desirable to match the output of the microwave source to the characteristics of the cavity for efficient operation.

Abstract: A microwave introduction device includes a microwave generator for generating a microwave of a predetermined frequency, a mode converter for converting the microwave into a predetermined oscillation mode, a planar antenna member arranged toward a predetermined space, and a coaxial waveguide connecting the mode converter with the planar antenna member to propagate the microwave. A central conductor of the coaxial waveguide is formed in a cylindrical shape, an inner diameter D1 of the central conductor is not smaller than a first predetermined value, and an outer conductor of the central conductor is also formed in a cylindrical shape. A ratio r1/r2 of a radius r1 of an inner diameter of the outer conductor to a radius r2 of an outer diameter of the central conductor is maintained at a second predetermined value and the inner diameter D2 the outer conductor is not greater than a third predetermined value.

Abstract: A high-frequency heating apparatus of the present invention includes a heating chamber to which a heating plate for loading a subject to be heated thereon is detachably attached, a microwave generating unit, a waveguide for transmitting a microwave from the microwave generating unit, a rotation antenna for radiating the microwave into the heating chamber from the waveguide, a driving unit for turning/driving the rotation antenna, an operating portion capable of choosing the grill menu by which the subject to be heated put on the heating plate is heated and a hot-up menu by which the subject to be heated is heated without the heating plate, and a controlling unit for controlling the driving unit based on an output signal form the operating portion, wherein the controlling unit controls to vary a direction of a sharp portion of a radiation directivity of the rotation antenna in response to the output signal from the operating portion.

Abstract: Methods and apparatuses for separating metal values, such as nickel and nickel compounds, from mineral ores, including lateritic ores are disclosed. The method includes providing a mixture of particles (e.g., crushed and sized ore) that is composed of at least a first group of particles and a second group of particles. Group members have similar chemical composition, while particles belonging to different groups have dissimilar chemical compositions. The mixture of particles is concurrently, or generally concurrently, heated (using microwave/millimeter wave energy) and exposed to a reactant. The wave energy and the reactant act to increase the difference in either the magnetic susceptibility or other separation properties between the first and second group of particles. The mixture of particles is then passed through an appropriate separator to separate the particles of interest. Optional steps are disclosed for purifying selected particles.

Abstract: The present invention relates a microwave applicator for heating a sample by microwave radiation which is transmitted via an at least partially tapering transmission duct from a microwave source to a cavity adapted to receive the sample to be heated. The transmission duct has at least one external wall, said wall defining an internal space for the propagation of said microwave radiation and comprising an interface which is at least partially permeable to said microwave radiation. The interface is at least partially arranged within said tapering portion of the duct. The duct is adapted to form a jacket surrounding the cavity with said interface forming an inner wall of said jacket.

Abstract: A microwave applicator assembly includes a microwave applicator that excites TE modes and provides a generally circular heating pattern in a lossy dielectric material. The microwave applicator has a processing chamber bounded by a circumferential wall in which a plurality of indents are formed. The microwave applicator assembly may further include a feed waveguide coupled to the microwave applicator for inputting microwaves into the processing chamber. The microwave applicator assembly may further include one or more choking sections in communication with the processing chamber to enhance heating efficiency and reduce microwave leakage.

Abstract: A new, comparatively small type of microwave system based on open-ended applicators is disclosed. The applicator according to the invention uses a main evanescent and a propagating mode in combination, where the combination results in a cancellation of the horizontal magnetic fields at the ends of at least two opposing walls. The effect of this is that the fields propagating out of the applicator become concentrated to the applicator centreline (axis) region, provides an efficient heating of a load or assembly of loads, as well as a stable impedance matching of the system under variable loading conditions due to the mode evanescence, while not leaking energy between adjacent applicators. The applicator can also be used for direct feeding of an underlying small closed metal cavity, for providing (the same favourable) mode conditions to a load in this cavity.

Abstract: A system for melting a substance may be provided. The system may comprise a crucible insulated with fused silica, a microwave generator configured to supply microwaves, and at least one burner probe extending into the crucible. The at least one burner probe may comprise a wave guide. The wave guide may be configured to receive microwaves from the microwave generator and transmit the microwaves. The at least one burner probe may further comprise an absorber. The absorber may have a geometry configured to cause a minimal amount of microwave energy to be reflected back into the wave guide. In addition, the absorber may comprise a one piece cast of silicon carbide configured to dissipate heat along an exterior of the absorber. The absorber may be further configured to receive the microwaves from the wave guide and convert energy from the microwaves into the heat.

Abstract: A microwave applicator comprising a coaxial electrical input (4) and a waveguide (1) filled with dielectric (2), an inner conductor (7) of the coaxial input extending longitudinally within one end of the waveguide to launch microwaves in the TM01 mode to travel to the distal end face (8) of the waveguide so that microwaves are transmitted when the distal end face is contacted by the biological tissue to be treated.

Abstract: A system for melting a substance may be provided. The system may comprise a microwave generator, at least one wave guide, a melter assembly, and at least one thermal insulator. The at least one wave guide may connect the microwave generator to at least one power transfer element. The at least one wave guide may be configured to transfer microwave energy from the microwave generator to a refractory assembly. The melter assembly may comprise the refractory assembly and the at least one power transfer element connected to the refractory assembly. The refractory assembly may comprise at least one absorption element configured to transfer microwave energy, received from the at least one power transition element, into heat energy. The at least one thermal insulator may be configured to allow the microwaves to penetrate to the at least one absorption element.

Abstract: In a microwave irradiation apparatus, an applicator portion has an interior space for housing an object to be irradiated. A first microwave irradiation system outputs a first microwave to the interior space in a first mode so as to generate a large electric field and a small magnetic field at a specific place of the interior space. A second microwave irradiation system outputs a second microwave having a polarization plane crossing a polarization plane of the first microwave to the interior space in a second mode so as to generate a large magnetic field and small electric field at the specific place of the interior space.

Abstract: The present invention relates to an improved reactor, which allows microwave-assisted processing of feedstocks or mixtures of hydrocarbons, and the operating system thereof, which operates under high temperatures and pressures of hydrogen or other gases, in continuous of batch mode. The invention relates to modifications in the geometric configuration of the reactor to process diverse hydrocarbon feedstocks, with or without the addition of catalysts, in the presence or absence of hydrogen or other gases, forming a system which includes a reaction vessel and associated devices, so as to to allow better transmittance of the radiation onto the feedstock to be processed and guarantee maximum absorption of the microwaves by the the reaction medium irrespective of the composition thereof.

Abstract: A microwave plasma apparatus for processing a material includes a plasma chamber, a microwave radiation source, and a waveguide guiding microwave radiation from the microwave radiation source to the plasma chamber. A process gas flows through the plasma chamber and the microwave radiation couples to the process gas to produce a plasma jet. A process material is introduced to the plasma chamber, becomes entrained in the plasma jet, and is thereby transformed to a stream of product material droplets or particles. The product material droplets or particles are substantially more uniform in size, velocity, temperature, and melt state than are droplets or particles produced by prior devices.

Abstract: An apparatus for heat treating manufactured components using microwave energy and microwave susceptor material. Heat treating medium such as eutectic salts may be employed. A fluidized bed introduces process gases which may include carburizing or nitriding gases The process may be operated in a batch mode or continuous process mode. A microwave heating probe may be used to restart a frozen eutectic salt bath.

Abstract: A microwave energy applicator radiating uniformly all around the applicator that maintains high efficiency Voltage Standing Wave Ratio (V.S.W.R.) for surrounding media of dielectric constants varying from about 1 to about 80. In a particular embodiment, the high efficiency V.S.W.R. is less than about 1.3:1. The applicator can include a circular polarizer connectable to a dielectric waveguide radiator. The radiator can be substantially solid and include a substantially circular outer cross-section that tapers to an end. In one embodiment, the radiator includes a conical void formed in a dielectric entry section.

Abstract: A high voltage input apparatus for a magnetron, in which first protrusions formed on lead conductors are caught by insulators and an insulating case, a ground metal is bonded to the insulating case, and expanded portions formed on the insulators are caught by the insulating case and the ground metal, thereby firmly fixing the lead conductors and preventing the lead conductors from being undesirably separated from the insulators and the insulating case.

Abstract: A method and apparatus for reducing organic waste. The apparatus comprises a conveyor to move waste to a first chamber for weighing waste and purging oxygen, a second chamber for treating, sterilizing and reducing waste by reverse polymerization, and a third chamber for cooling reduced and sterilized waste.

Abstract: A rectangular microwave applicator operating at a predetermined frequency and comprising a microwave enclosure forming a cavity having first and second transverse dimensions and a longitudinal dimension n the direction of propagation of microwave energy, wherein said dimensions are such that a main power-transferring Teym1n mode with a long vertical wavelength is enhanced, and a significant amplitude of a complementary Teym2n mode is created, wherein m1, m2 and n are positive odd integers and m2 and n are both less or equal to m1-2.

Abstract: A dielectric heating system with which the power density applied to the product being treated can be at least doubled without risk of electric arcs. This invention is particularly suitable for treatment of compounds that absorb electromagnetic waves weakly (low dielectric constants). In particular, fatty substances such as oils, butters, waxes and fats can be treated (refining, hydrolysis, transesterification, interesterification, etc.), derivatives thereof (esterification, polymerization, alcoholysis, ethoxylation, hydrogenation, etc.) under static or dynamic conditions, as can hydrocarbons and aromatic compounds. This system can also be used advantageously for polar or polarized compounds, because the power absorbed is increased very significantly, with large production gains. In particular, fatty or non-fatty alcohols (oleic alcohol, glycol, glycerol, mannitol, sorbitol, polyglycerols, vitamins, etc.), carboxylic acids, amines and similar compounds can be treated under static or dynamic conditions.

Abstract: A method and apparatus for creating uniform heating of an microwave absorptive target. A microwave housing has a longitudinal axis and propagates a waveguide mode at an operating frequency. The target is located in an axial cross-sectional area relative to the longitudinal axis. First layer conductive strips are layered proximal to an inner wall of the microwave housing, substantially parallel to the longitudinal axis and being separated from an adjacent first layer conductive strip by a respective first layer gap, the inner wall acting as a ground plane. Second layer conductive strips are layered proximal to the first layer of conductive strips, parallel to the longitudinal axis and being separated from an adjacent second layer conductive strip by a respective second layer gap. Each first layer gap is centered under a respective second layer conductive strip and each second layer gap is centered over a conductive layer.

Abstract: An electron tube for communication is provided with an output waveguide that is directly coupled to an outlet port of a RF (Radio Frequency) wave signal, and at least one of a low-pass filter, a high-pass filter, and a band-pass filter is included inside the output waveguide.

Abstract: A magnetron arrangement has a coaxial output terminating in a probe which launches energy from the magnetron along a rectangular waveguide. The coaxial output is arranged in an endfire configuration with respect to the waveguide, giving a compact arrangement compared to conventional output designs.

Abstract: Cleaning a microwave device, in particular for drying print substrate in a printing machine, with a microwave source providing an irradiation field and a resonator chamber, wherein a microwave-penetrable material on the inside surfaces of the resonator chamber for forming a material layer that allows any dirt accumulated on it to protrude into the irradiation field.

Abstract: The invention concerns a device for microwave treatment in an applicator (1), characterized in that it comprises, arranged in the applicator, impedance adapting dielectric means (2, 7, 8) having shapes and dimensions adapted to the objects (10) to be treated and to the characteristics of wave propagation modes.

Abstract: Heating a printing substance and/or toner, in an electrophotographic printer, with a standing microwave formed by at least one cavity resonator, with the printed matter being caused to move through the resonator gap. The power distribution of the microwave applied by the resonator is shaped and configured for specific application requirements.

Abstract: An apparatus and method for heating a sample, such as chemical reaction mixtures are disclosed. The apparatus may include at least a microwave generator, a waveguide for guiding the generated microwaves to an applicator, and a deflector formed by a closed loop defining a plane. The deflector may have an inherent resonance frequency and a thickness in a direction normal to the plane. The deflector may be rotatable around an axis being at least substantially parallel to the plane, and positioned in the waveguide so as to form a resonant cavity with the sample and the waveguide applicator. The resonance conditions of the resonant cavity and the coupling factor of radiation from the waveguide to the cavity may be easily adjustable by rotating the deflector. The resonance conditions and the coupling factor may be adjusted in response to the dielectric properties of the sample in order to optimize the amount of absorbed power and thereby obtain control of the sample heating process.

Abstract: An integrated circuit package which has a thermal epoxy that can be attached to an integrated circuit and a thermal element. The thermal epoxy can be cured with energy at a microwave frequency. Curing the thermal epoxy with microwave energy can minimize package warpage during the curing process.

Abstract: A microwave applicator for heating loads being a waveguide transition between the rectangular TE10 and TE20 modes comprising a TE10 mode section and a TE20 mode section. The location of the load being inside said TE20 mode section and with its major axis perpendicularly to the major propagation direction of the TE20 mode, close to a shorting wall of said TE20 mode section and also close to the centreline of said propagation direction.

Abstract: A method, apparatus and article of manufacture for providing electromagnetic drying of printed media. A resonant cavity allows support of standing waves along many radial axes throughout the resonant cavity. The electromagnetic drying unit allows forced air to be introduced into the resonant cavity, thereby reducing moisture within the resonant cavity and extending the life of the resonant cavity. Input and output openings may be arranged longitudinally along the resonant cavity and may be designed to substantially reduce the amount of electromagnetic radiation emanating from them during operation. A honeycomb feature at the end of the resonant cavity may allow egress of the forced air, while substantially reducing the amount of electromagnetic radiation emanating from the end of the resonant cavity.

Abstract: A method, apparatus and article of manufacture for providing electromagnetic drying of printed media. A resonant cavity allows support of standing waves along many radial axes throughout the resonant cavity. The electromagnetic drying unit allows forced air to be introduced into the resonant cavity, thereby reducing moisture within the resonant cavity and extending the life of the resonant cavity. Input and output openings may be arranged longitudinally along the resonant cavity and may be designed to substantially reduce the amount of electromagnetic radiation emanating from them during operation. A honeycomb feature at the end of the resonant cavity may allow egress of the forced air, while substantially reducing the amount of electromagnetic radiation emanating from the end of the resonant cavity.

Abstract: Cleaning a microwave device, in particular for drying print substrate in a printing machine, with a microwave source providing an irradiation field and a resonator chamber, wherein a microwave-penetrable material on the inside surfaces of the resonator chamber for forming a material layer that allows any dirt accumulated on it to protrude into the irradiation field.

Abstract: A waveguide system for passing microwave energy while blocking foreign particles from a moving gas passing through the system is provided. The system includes first and second waveguide sections and a low loss microwave window disposed between the waveguide sections to allow microwave energy to pass from the first waveguide section through the window to the second waveguide section. The system also includes a gas bypass filtration system having a first port in communication with the first waveguide section, a filter element in communication with the first port, and a second port in communication with the filter element and with the second waveguide section. The system of the invention having these features blocks, by means of the window, a gas flowing through the first waveguide section and forces that gas to flow through the gas bypass filtration system so that it enters the second waveguide section only after passing through the filter. A system designed to include a pillbox window is also provided.

Abstract: A microwave energy applicator radiating uniformly all around the applicator that maintains high efficiency Voltage Standing Wave Ratio (V.S.W.R.) for surrounding media of dielectric constants varying from about 1 to about 80. In a particular embodiment, the high efficiency V.S.W.R. is less than about 1.3:1. The applicator can include a circular polarizer connectable to a dielectric waveguide radiator. The radiator can be substantially solid and include a substantially circular outer cross-section that tapers to an end. In one embodiment, the radiator includes a conical void formed in a dielectric entry section.

Abstract: A Microwave heating system includes an elongated cylindrical metal cavity intended for heating a voluminous elongated load. The system includes microwave feeding means arranged to generate a single mode of the circular type TEm;n;p (a so-called whispering gallery mode) inside the cavity in order to heat the elongated load, wherein the circumferential index m is at least 4, the radial index n=1 and the axial index p being >0. The heating system is preferably adapted for wood processing.

Abstract: The present invention provides low cost microfluidic devices having embedded metal conductors. The devices of the invention comprise a electronic component comprising a substrate having a first surface, a layer of electrically-conductive material deposited on a portion of the first substrate surface, a first sublayer of electrically-insulating material deposited on the first substrate surface and on the layer of electrically-conductive material, a second sublayer of electrically-insulating material deposited on the first sublayer of insulating material, and a third sublayer of electrically-insulating material deposited on the layer of dielectric material, and a fluid-handling component having a contoured surface affixed to the electronic component. The devices of the invention are advantageously used for performing electric field lysis and the polymerase chain reaction. The invention further advantageously provides simple, low cost methods for fabricating such microfluidic devices.

Abstract: Cleaning a microwave device, in particular for drying print substrate in a printing machine, with a microwave source providing an irradiation field and a resonator chamber, wherein a microwave-penetrable material on the inside surfaces of the resonator chamber for forming a material layer that allows any dirt accumulated on it to protrude into the irradiation field.

Abstract: A microwave applicator for heating a moving fluid includes a heating chamber having a fluid inlet and a fluid outlet and through which the fluid to be heated flows. The applicator also includes a microwave energy source and a microwave circuit having at least one wave-guide element. The microwave circuit transforms microwave energy from the microwave source into a cylindrical wave-guide mode within the heating chamber for uniformly heating fluid flowing through the heating chamber. This technology is also applied as a method for applying microwave energy for heating a moving fluid. This method includes passing a fluid from a fluid inlet, through a heating chamber, and out a fluid outlet; and applying a microwave energy source through a microwave circuit including at least one wave-guide element to transform microwave energy from the microwave energy source into a cylindrical wave-guide mode within the heating chamber to uniformly heat the fluid flowing through the heating chamber.

Abstract: The present invention relates to an apparatus for heating a sample, such as chemical reaction mixtures, whose dielectric properties varies during the heating process. In particular, the present invention relates to a microwave heating apparatus comprising a microwave generator, a waveguide for guiding the generated microwaves to an applicator, and a deflector formed by a closed loop defining a plane, said deflector having an inherent resonance frequency and a thickness in a direction normal to said plane, the deflector being rotatable around an axis being at least substantially parallel to said plane, the deflector being positioned in the waveguide so as to form a resonant cavity with the sample and the waveguide applicator. The resonance conditions of the resonant cavity and the coupling factor of radiation from the waveguide to the cavity are easily adjustable by rotation of the deflector.

Abstract: A microwave window structure for a low-pressure chamber is provided. The window structure enables microwave energy to be introduced into the chamber from a source external to the chamber. The window structure includes a fixture having electrically conductive walls. Inner portions of the walls provide a peripheral region of an aperture within such fixture. The fixture is adapted for mounting to a sidewall portion of the chamber. A solid, microwave energy transparent dielectric window is included. The window includes: a periphery portion affixed to the fixture; and, an inner region disposed within the aperture of the fixture.

Abstract: A plasma source for a spectrometer for spectrochemical analysis of a sample is characterized by use of the magnetic field component of applied microwave energy for exciting a plasma. The source includes a waveguide cavity (10) fed with TE10 mode microwave power. A plasma torch (16) passes through the cavity (10) and is axially aligned with a magnetic field maximum (18) of the applied microwave electromagnetic field. Magnetic field concentration structures such as triangular section metal bars (20) may be provided. In an alternative embodiment a resonant iris may be provided within a waveguide and the plasma torch positioned relative thereto such that the microwave electromagnetic field at the resonant iris excites the plasma.

Abstract: The invention relates to a process for drying wood, characterized in that it comprises a pressurizing step to place a sealed chamber (1) under a predetermined pressure by injecting or generating saturating steam and maintaining this pressure for a predetermined time interval, while ensuring a forced circulation of air and saturating steam within the chamber, a heating step to heat the wood core and central zone of the wood pieces by emitting microwaves at frequencies ranging between 400 and 2450 MHz, an evacuation step to carry away the liquid exudates from the wood when run down to the bottom of the chamber (1) where they are collected.

Abstract: A microwave window structure for a low-pressure chamber is provided. The window structure enables microwave energy to be introduced into the chamber from a source external to the chamber. The window structure includes a fixture having electrically conductive walls. Inner portions of the walls provide a peripheral region of an aperture within such fixture. The fixture is adapted for mounting to a sidewall portion of the chamber. A solid, microwave energy transparent dielectric window is included. The window includes: a periphery portion affixed to the fixture; and, an inner region disposed within the aperture of the fixture. A first surface of the inner region is disposed in the chamber and a second, opposite surface of the inner region widow being disposed external to the chamber. The window has a sidewall portion with a first end thereof terminating in the first surface and a second end thereof terminating at the periphery portion. The sidewall portion of the window is spaced from the walls of the fixture.

Abstract: Microwave heating system comprising an elongated cylindrical metal cavity intended for heating a voluminous elongated load.

Abstract: The present invention relates to an apparatus for heating a sample, such as chemical reaction mixtures, whose dielectric properties varies during the heating process. In particular, the present invention relates to a microwave heating apparatus comprising a microwave generator, a waveguide for guiding the generated microwaves to an applicator, and a deflector formed by a closed loop defining a plane, said deflector having an inherent resonance frequency and a thickness in a direction normal to said plane, the deflector being rotatable around an axis being at least substantially parallel to said plane, the deflector being positioned in the waveguide so as to form a resonant cavity with the sample and the waveguide applicator. The resonance conditions of the resonant cavity and the coupling factor of radiation from the waveguide to the cavity are easily adjustable by rotation of the deflector.

Abstract: A high-frequency heating apparatus includes a magnetron (1), a magnetron holding plate (2), a waveguide (3), a heating chamber (4), and screws (5), and the magnetron (1) is attached to the magnetron holding plate (2) with two screws. Hereby, attachment of the magnetron is facilitated, speed-up of the manufacturing process of the high-frequency heating apparatus can be realized, and production efficiency can be improved. Further, in the breakdown repair requiring exchange of the magnetron, working time can be also reduced, so that service to customers can be also improved.

Abstract: A microwave device has a monolithic microwave integrated circuit (MMIC) disposed therein for applying microwave radiation to a microfluidic structure, such as a chamber, defined in the device. The microwave radiation from the MMIC is useful for heating samples introduced into the microfluidic structure and for effecting lysis of cells in the samples. Microfabrication techniques allow the fabrication of MMICs that perform heating and cell lysing of samples having volumes in the microliter to picoliter range.

Abstract: A magnetron arrangement has a coaxial output (13) terminating in a probe (14) which launches energy from the magnetron along a rectangular waveguide (17). The coaxial output (13) is arranged in an endfire configuration with respect to the waveguide (17), giving a compact arrangement compared to conventional output designs.