155 results about "Circular waveguide" patented technology

The invention aims at providing a microwave-spalling agent in-situ fracturing device and method for mining rock through drilling, and belongs to the technical field of drilling mining. A rectangular waveguide and a circular waveguide are matched with a coaxial inner core to achieve focused radiation, directional initial fractures are generated in a drilled hole according to a preset angle, and the directional initial fractures are fractured; and then a static spalling agent is injected into the initial fracture in a segmented and partial pressure mode, in-situ secondary fracturing is conducted on the basis of the microwave fracturing range by means of the fracture expansion effect brought by expansion pressure, and secondary expansion of the fracture is promoted. And by superposing the fracturing ranges of the microwaves and the spalling agent, a large-area communicated fracture network mainly comprising microwave directional fractures is formed. Finally, on the premise that the fracturing range and effect are guaranteed, the purposes of reducing mining drill holes, increasing the distance between the drill holes and improving the mining efficiency are achieved.

The invention belongs to the field of particle accelerator microwaves, and particularly relates to a C-band compact spherical microwave pulse compression device which comprises a shell, a dual-polarization mode coupler and a circular waveguide, a spherical energy storage cavity is formed in the shell, and the circular waveguide and the spherical energy storage cavity are communicated through a coupling hole; the dual-polarization mode coupler comprises a rectangular waveguide, a butterfly-shaped matching section and a cylindrical matching section. According to the klystron radio frequency pulse compression circuit, the radio frequency pulse with the pulse width of 2.5 microseconds of the klystron can be compressed to 300ns, the average power gain in a single pulse is more than 4 times, the peak power gain is 6.3 times, and the compression efficiency is about 54%. According to the dual-polarization mode coupler, the functions of power distribution, mode conversion and polarization mode generation are synchronously realized, a TE10 mode in a rectangular waveguide is converted into two polarization TE11 modes which are equal in amplitude and orthogonal in phase, and then the two orthogonal TE114 modes are excited in a spherical energy storage cavity.

The invention discloses a gradient refractive index efficient microwave heater and an analogue simulation method, and relates to the technical field of microwave heating devices.The heater comprises an asymmetric transmission circular waveguide, a transition part, a cylindrical medium and a heating load which are sequentially communicated, and the outer diameter of the cylindrical medium is smaller than that of the asymmetric transmission circular waveguide; the transition part is a connecting piece for connecting the asymmetric transmission circular waveguide and the cylindrical medium, the tail end part of the cylindrical medium extends into the heating load, and a metasurface structure with a gradient refractive index is arranged in the asymmetric transmission circular waveguide. One-way transmission of electromagnetic waves is achieved through the metasurface structure with the gradient refractive index, and then electromagnetic energy is concentrated into a medium used for plug-in heating. According to the heater, the cylindrical medium is inserted into the load to efficiently heat materials with different shapes, the dielectric constant range of the materials changes from 8 to 80, and a simulation result shows that the heating efficiency is always higher than 90% when the dielectric constant of the load is in the dynamic range of 8-80.

The invention discloses a relativistic magnetron with an energy feedback structure, and belongs to the technical field of microwaves. The relativistic magnetron is of a full-cavity extraction structure and comprises an anode, a cathode, an energy extraction structure and a guide magnetic field coil. According to the energy extraction structure, an annular microwave reflecting plate is adopted in an output circular waveguide part, part of energy is reflected back to a gap between a cathode and an anode, the interaction between electron cloud and space electromagnetic waves is enhanced, and the output power of a relativistic magnetron is improved. According to the relativistic magnetron, the output power of the relativistic magnetron is effectively improved while the compactness of the device is ensured; meanwhile, the energy feedback structure is simple and easy to process.

According to one embodiment, an introduction-side rectangular waveguide tube and a lead-out-side rectangular waveguide tube are each connected to a circular connection plate connected to an end surface of the circular waveguide tube, and at least one connection plate includes, in an outer circumference thereof, the other welding collar welded to the one welding collar, and both the one welding collar and the other welding collar include grooves or holes for a rotation regulation jig to regulate rotation in a circumferential direction, and an entire portion along the circumferential direction including the grooves or holes is welded and fixed thereto.

The invention provides a Faraday isolator which is characterized in that a circular waveguide is integrally X-shaped, four corners adjacent to the circular waveguide are respectively provided with a threaded hole, two sides of the circular waveguide are respectively provided with an X-shaped cavity, a steel sheet is X-shaped, a pair of step waveguides are respectively arranged on two sides of the circular waveguide, and a pair of step waveguides are respectively arranged on two sides of the steel sheet. The pair of steel sheets, the ferrite, the absorber and the plurality of magnetic steels are all installed in the circular waveguide, the plurality of magnetic steels are arranged around the ferrite, the pair of ceramic cones with membranes are respectively installed at two ends of the ferrite, the pair of support rings are respectively installed at two sides of the absorber, and the pair of support rings are respectively installed at two ends of the absorber. The middle parts of the pair of stepped waveguides are provided with stepped waveguide inner cavities, the middle part of the circular waveguide is provided with a circular waveguide inner cavity, and one ends, far away from the ferrite, of the pair of ceramic cones with films respectively penetrate through the pair of supporting rings and respectively extend into the stepped waveguide inner cavities of the pair of stepped waveguides. The inner cavity of the stepped waveguide and the inner cavity of the circular waveguide are both provided with gold-plated surfaces.

The invention discloses a microwave antenna with a low side lobe. The microwave antenna comprises a main reflecting surface, a feed source and a surrounding edge, wherein the main reflecting surface is of a rotating paraboloid structure, and a feed source is arranged at the focus of the main reflecting surface; the feed source comprises a radiation source, an auxiliary reflecting surface, a circular waveguide and a dielectric ring arranged on the splashing plate; the surrounding edge is arranged around the edge of the main reflecting surface and is used for absorbing signals exceeding the receiving range of the main reflecting surface; geometric parameters of the dielectric ring are configured to enable a feed source directional diagram to conform to improved generalized Taylor displacement distribution, an expression of the improved generalized Taylor displacement distribution is # imgabs0 #, rb is a center shielding radius, B1 is a constant larger than 0.45, J0 is a value of a first zero point of a zeroth-order Bessel function, and the feed source directional diagram is adjusted by adjusting the geometric parameters of the dielectric ring on the basis of the expression. And the microwave antenna can achieve the effect of low side lobe.

The present invention discloses a rapid switching device for a Ku and Ka dual-frequency transceiver assembly, which includes a base, an azimuth electrical compartment arranged on the base, an external battery and an elevation electrical compartment arranged on the azimuth electrical compartment, and an antenna surface and a polarization rotation assembly arranged on the elevation electrical compartment. One end of a Ku circular waveguide extension passing through the antenna surface is provided with a Ku feed rod, and the other end is provided with a Ku transceiver. This rapid switching device for the Ku and Ka dual-frequency transceiver assembly facilitates the rapid replacement of the Ku / Ka frequency bands, while retaining the automatic polarization satellite alignment rotation, ensuring that the overall weight of the device is relatively light and it is convenient to use. If the polarization of the Ku frequency band needs to be manually adjusted, then each time it is necessary to log in to the device wirelessly or wired to view the current polarization angle; or manually switch after finding the polarization angle through the screen, and the device is very inconvenient to use.

The application discloses a ternary computing method and system based on a double-chain difference coupling principle. A difference value (XnYn) is directly generated by a forward component Xn and a reverse component Yn in a difference coupling area, forming a three-value logic {‑1, 0, +1}, and a threshold comparison circuit is omitted, and operation follows BH=Σ(XnYn)×3^n. A hierarchical logic system composed of basic operators, minimum complete operators and global operators is constructed, and arbitrary three-value logic operation is realized; a circular waveguide structure is adopted to configure an optical path difference, so that coherent light directly forms three interference states at an output end, and optical three-value logic gates and optical full adders are realized; a double-chain six-bit structure is adopted for symbol coding, a two-dimensional geometric framework is driven to generate a symbol form, and logical and geometric expression unification is realized.

The present invention discloses a broadband, high-efficiency circular waveguide TE31 mode exciter, belonging to the field of microwave and millimeter wave technology. The exciter comprises a standard TE10 mode rectangular waveguide section, a TE10 mode-TE30 mode conversion section, a standard TE30 mode rectangular waveguide section, a TE30 mode-TE31 mode conversion section, and a TE31 mode circular waveguide section, all connected in sequence. The excitation process of the TE31 mode exciter is divided into two steps: first, converting the TE10 mode to the TE30 mode, and then converting it to the TE31 mode. With the cooperation of a power divider, a torsion waveguide, and a gradient waveguide, the conversion from the rectangular waveguide TE10 mode to the circular waveguide TE31 mode is achieved, reducing losses during the conversion process and ensuring conversion efficiency.

The invention discloses a millimeter wave communication antenna broadband feed source network four-port device and an application method thereof, and relates to the technical field of microwave communication, the millimeter wave communication antenna broadband feed source network four-port device comprises a circular rectangular transition structure, a circular polarizer and an orthogonal mode coupling duplexer assembly which are integrated in sequence; the circular rectangular transition structure is used for corresponding conversion transition between the standard rectangular waveguide and the circular waveguide; the circular polarizer is provided with an orthogonal stepped ridge, so as to convert the circularly polarized wave into an orthogonal linearly polarized wave or convert the orthogonal linearly polarized wave into the circularly polarized wave corresponding to the signal receiving and transmitting direction; the orthogonal mode coupling diplexer assembly is used for separating the two paths of orthogonal linear polarized waves in the synthetic state or synthesizing the two paths of orthogonal linear polarized waves in the separated state corresponding to the signal receiving and transmitting direction, and can screen signals passing through a specific receiving and transmitting frequency band. The technical problems that in the prior art, a dual-polarized antenna technology for dual-channel communication is large in size, complex in structure and high in cost, and the overall performance is difficult to meet expected requirements are solved.

The invention discloses a spiral structure waveguide for vortex light topological charge conversion and an implementation method thereof, and belongs to the field of optical waveguides. The circular waveguide and the spiral structure are combined, the spiral structure is used for regulating and controlling the vortex light mode according to the mode conversion matching condition, and vortex light conversion between any topological charge orders is achieved; according to the invention, complete conversion between different vortex lights is realized, two vortex light mixed beams with different proportions can be generated, and the requirements of generation and utilization of vortex lights with different orders in an integrated photonics on-chip structure are met. According to the method, the problem that topological charges cannot be freely converted among different vortex light modes in a waveguide structure is solved, the application value of the waveguide structure in the aspect of vortex light regulation and control is expanded, and the possibility is provided for an integrated photon platform to utilize vortex light topological charge degree-of-freedom coding information and process calculation tasks. According to the invention, information coding, optical communication, calculation and other applications are carried out by changing the topological charge of the vortex light.

A cap feed source structure disclosed by the present invention comprises a protective cap, a medium support member and a circular waveguide, the circular waveguide and the medium support member are fastened through a triangular step, and the medium support member and the protective cap are fastened through a thread. The medium supporting piece is made of cross-linked polystyrene, so that the stable wave-transparent performance of the whole material is ensured; the upper end surface of the dielectric support member is metalized to ensure the microwave reflection efficiency of the end surface; metallization treatment is carried out on the upper end surface of the medium supporting piece, a mature vacuum plating process is adopted, copper plating and nickel plating are carried out on the material, and a plating layer is firm and reliable; the circular waveguide and the dielectric support member are assembled by a process of first partial assembly and then welding forming, so that the connection quality of the two devices is effectively ensured; the protective cap is made of a cross-linked polystyrene material and protects the metalized surface of the upper end of the supporting medium piece.

The invention discloses a quasi-single-mode circular waveguide conical horn antenna, a radar and a communication device. The quasi-single-mode circular waveguide conical horn antenna comprises a circular waveguide section and a conical horn section. Conductor loss is reduced by remarkably increasing the diameter of the circular waveguide, and axial periodic annular grooves are formed in the inner wall of the circular waveguide to form a spatial mode filter and a selective attenuation high-order mode, so that high radiation efficiency and high mode purity are realized at the same time in a millimeter wave frequency band. And the conical horn section adopts an index profile to realize high-directionality radiation. The antenna structure effectively solves the technical problems of large loss and impure mode in a millimeter wave high-frequency band in the traditional design.

A triple-mode monopulse tracking antenna and antenna system with risley prism beam steering. In particular, a monopulse tracking antenna, comprising: a triple-mode circular waveguide horn, configured to generate three monopulse patterns; at least two Risley prisms, each positioned a fixed distance from the triple-mode circular waveguide horn, configured to receive and steer the three monopulse patterns, wherein each Risley prism is coated with an anti-reflective layer; a means for axially rotating each of the at least two Risley prisms; and a parabolic phase correcting surface, positioned intermediately between the triple-mode circular waveguide horn and at least two Risley prisms.

The invention discloses a broadband circular waveguide TE01 mode exciter based on a crossed ridge waveguide, and relates to the technical field of microwaves. The exciter comprises a rectangular waveguide four-path power division feed structure for dividing the power of a TE10 mode into four paths, a crossed ridge waveguide TE22 mode forming structure for synthesizing the four paths of TE10 modes into a crossed ridge waveguide TE22 mode, and a circular waveguide TE01 mode forming structure for converting the crossed ridge waveguide TE22 mode into a circular waveguide TE01 mode. By introducing the crossed ridge waveguide structure, the directional regulation and control of waveguide dispersion are realized, and the cut-off frequency interval between a working mode and a parasitic mode is remarkably improved, so that the bandwidth is expanded. A crossed fan-shaped structure is introduced to serve as a middle structure of the crossed ridge waveguide and the circular waveguide, the cut-off phenomenon caused by sudden change of the waveguide shape is avoided, and the working bandwidth is further expanded. The high-purity and high-efficiency broadband filter has the advantages of being high in purity, high in efficiency, wide in frequency band and high in compactness, meanwhile, the structure is simple, machining and assembling are easy, and good engineering practicability is achieved.

In one embodiment, the present disclosure is directed to a system for providing improved electric field uniformity to a plasma chamber receiving multiple signal inputs. The system includes one or more dielectrics distributing received energy to one or more antennas. The one or more dielectrics have N receiving areas. N circular waveguides are positioned over the N receiving areas. Each of waveguides has a mode converter converting a received first transverse mode signal to a second transverse mode signal to be output by the circular waveguide to the corresponding receiving area. At least one phase adjuster circuit adjusts the phase of at least one of the first transverse mode signals such that adjacent circular waveguides have their received first transverse mode signals differ in phase by approximately 360 / N.

The application discloses a gynecological millimeter wave therapeutic instrument, which comprises a host computer, an antenna mechanism connected with the host computer, the antenna mechanism comprising sequentially connected circular waveguide, millimeter wave antenna and antenna protective cover, the host computer and the antenna mechanism being connected along the same axial direction. The host computer comprises a millimeter wave source and a wave form conversion and attenuation device, the wave form conversion and attenuation device comprising an attenuation unit and a wave form conversion unit integrated into one mechanism, the attenuation unit being connected with the millimeter wave source through a flange, the wave form conversion unit being connected with the circular waveguide, the attenuation unit being adapted to attenuate the millimeter wave power emitted by the millimeter wave source to a target value, and the wave form conversion unit being adapted to convert the field type of the millimeter wave after power attenuation from TE10 wave in the rectangular waveguide into circular polarization wave in the circular waveguide, so as to provide the required millimeter wave output power for the millimeter wave antenna. The gynecological therapeutic instrument can perform accurate irradiation treatment in the gynecological cavity, and can ensure a larger millimeter wave adjustment range without changing the millimeter wave source.

The invention provides a shielding structure of a plasma source, a design method of the shielding structure and plasma processing equipment, and relates to the technical field of electromagnetic shielding, the plasma source comprises a solenoid, the shielding structure comprises a shielding body surrounding the solenoid, and the shielding body is provided with at least one shielding channel designed based on the cut-off waveguide theory. The method is used for suppressing electromagnetic leakage on the premise of ensuring physical communication. The shielding channel comprises a ventilating window which is arranged on the side surface of the shielding body and is used for radiating, a circular waveguide tube which is used for a pipeline to pass through and is connected with an external hose fixing piece and is provided with a thread, and a segmentable waveguide tube which is used for a growth sample cavity to pass through. By constructing a shielding body, a solenoid in a plasma source is shielded in all directions; by reasonably designing the size and layout of the waveguide structure, efficient suppression of radio frequency energy is realized, the failure of the sensor caused by electromagnetic interference is solved, and stable operation of plasma processing equipment is guaranteed.

The present invention discloses a rotary microwave filter power divider, which resonates with TM 010 The choke slot loaded circular waveguide cavity of the mode and the circular symmetric loaded circular waveguide cavity of the coaxial probe are coupled through a common metal ring. 010 The circular symmetry of the mode field, the external quality factor control of the output coaxial probe and the coupled equal-amplitude and in-phase field, and the internal field continuity provided by the choke slot simultaneously achieve the functions of filtering, power division and stable output signal during rotation, forming a rotary filter power divider with the characteristics of low cost, small size, low loss and simple structure.

The invention discloses an antenna optimization method, system and device based on a QVE frequency band feed source network, and a medium, and relates to the technical field of antennas. The method comprises the following steps: acquiring a QVE frequency band illumination angle parameter and an edge illumination level parameter; calculating the standard radius of the circular waveguide and establishing a longitudinal groove geometric parameter constraint relation to obtain longitudinal groove differential geometric parameters; determining a first orthogonal support arm length deviation value and a broadside structure parameter of the first-stage turnstile structure by taking a preset phase difference angle of orthogonal polarization radio frequency signals of the first-stage turnstile structure as a target; constructing a dual circular polarization network and a stepped transition structure; constructing a power combiner and a Chebyshev impedance matcher; and integrating the differential longitudinal slot feed source, the dual-circular polarization network and the orthogonal mode converter to obtain a QVE frequency band feed source network, and performing antenna feed through the QVE frequency band feed source network. By implementing the technical scheme provided by the invention, the feed efficiency of the antenna system can be improved, so that the performance of the antenna system is enhanced.

The utility model provides a compact dual-circular polarization bandwidth horn, a circular polarizer comprises a circular waveguide, the front end of the circular polarizer is connected with two waveguide impedance matchers, and a stepped diaphragm is arranged in the circular waveguide to divide the circular waveguide into two sides. The stepped diaphragms in the circular waveguide are utilized to enable the signals to form left-hand circular polarization and right-hand circular polarization respectively, efficient conversion and separation of the left-hand circular polarization signals and the right-hand circular polarization signals are achieved, and therefore a complex orthogonal mode converter in the prior art is omitted, and the dual-circular-polarization horn is simple and compact in structure, light in weight and low in cost. The manufacturing difficulty and the processing cost are reduced, and unnecessary mode coupling and energy loss can be avoided. The compact dual-circular polarization bandwidth horn has the advantages of wide bandwidth, high isolation, low axial ratio, good circular polarization performance, compact structure, light weight, easy processing and the like.

The invention discloses an input coupler of a convolution traveling wave amplifier, and belongs to the technical field of microwave devices. The coupler for converting the rectangular waveguide TE10 mode into the circular waveguide TE11 mode structurally and mainly comprises an input rectangular waveguide, an electron beam circulation end and an output circular waveguide, the rectangular waveguide is connected with the circular waveguide, and the electron beam circulation end is completely communicated with the output circular waveguide. The electron beam circulation end is composed of a plurality of cylindrical resonant cavities, and the number, the radius and the width of the cylindrical resonant cavities are matched with the working frequency of the device. Compared with a traditional input coupler, the input coupler disclosed by the invention ensures that a TE11 mode is output by the output circular waveguide in a single direction by utilizing a multi-diffraction principle of a plurality of cylindrical resonant cavities, and the transmission and purity of the output circular waveguide TE11 mode can be improved; meanwhile, the electron beam circulation end is an open end, and a large space can be provided for electron beam circulation.

The invention discloses a high-power-capacity power divider based on a mixed mode, and belongs to a power distribution / synthesis technology in the technical field of high-power microwaves. The objective of the invention is to solve the problems of insufficient power capacity and coaxial inner conductor end surface electric field concentration caused by small cross section size when an existing power divider is applied to high frequency. The power divider integrates circular waveguide TM0n mixed mode excitation, conversion from a mixed mode to a coaxial waveguide TEM mode and an inner conductor end face strong field control technology, and comprises an input circular waveguide, inclined plane transition, a large over-mode ratio circular waveguide, a coaxial waveguide, a radial line and a rectangular waveguide, and a groove is formed in the inner conductor end face of the coaxial waveguide. While the waveguide section is increased to improve the power capacity of the main body structure, the end surface electric field peak value is effectively inhibited, and the system power capacity is improved. The invention is mainly applied to a microwave system requiring high power distribution or synthesis, and has the advantages of high power capacity, low surface electric field, high conversion efficiency and wide working bandwidth.

The application discloses a kind of based on super surface rectangular waveguide mode conversion device and method, for realizing TE 10 -TE 20 -TE 01 Metal waveguide mode conversion, rectangular waveguide mode conversion device includes first to fifth section waveguide, and first to second super surface structure, wherein: first, third, fifth section waveguide is used to transmit rectangular waveguide TE 10 Mode, rectangular waveguide TE 20 Mode and circular waveguide TE 01 Mode, second, fourth section waveguide is used to generate multimode interference;First super surface structure is used to realize TE 10 Mode to TE 20 Mode conversion, second super surface structure is used to realize TE 20 Mode to TE 01 Mode conversion;Second section waveguide, first super surface structure and third section waveguide constitute TE 10 -TE 20 Mode converter;Fourth section waveguide and second super surface structure constitute TE 20 -TE 01 Mode converter.The application utilizes the regulation and control ability of super surface to electromagnetic field, and rectangular waveguide TE 10 Mode can be converted into circular waveguide TE 01 Mode in smaller space.

The present invention discloses a K / Ka band dual-frequency conical beam antenna, comprising a high-frequency filtering and feeding module, a low-frequency power splitting and feeding module, and a nested horn module; the nested horn module comprises a circular waveguide horn and a coaxial horn nested outside the circular waveguide horn; the high-frequency filtering and feeding module is used to filter and perform mode conversion on input high-frequency electromagnetic energy, and output electromagnetic waves in a coaxial TEM mode; the electromagnetic waves in the coaxial TEM mode are used to excite the circular waveguide horn; the low-frequency power splitting and feeding module is used to perform power distribution on the input low-frequency electromagnetic energy, and output a plurality of electromagnetic waves with equal amplitude and phase; the plurality of electromagnetic waves with equal amplitude and phase are used to symmetrically excite the coaxial horn; the present invention can realize the radiation characteristics of a dual-band dual-conical beam, effectively improving the detection range of the antenna; the filtering function is integrated in the high-frequency filtering and feeding module, effectively improving the anti-interference capability of the antenna; and at the same time, it has high power capacity and radiation efficiency.

The utility model provides a feed source assembly and a parabolic antenna, and the feed source assembly comprises a housing which is provided with an accommodation cavity; the reflecting plate is arranged on the shell and is accommodated in the accommodating cavity; the vibrator is arranged on the reflecting plate and is accommodated in the accommodating cavity; the supporting tube is arranged on the shell, the supporting tube and the vibrator are distributed at intervals, the supporting tube is provided with a wire passing channel communicated with the containing cavity, and the wire passing channel is used for a coaxial cable to penetrate through so that the two ends of the coaxial cable can be connected with the vibrator and the signal source respectively; the connecting disc is arranged at one end, far away from the shell, of the supporting pipe, and the connecting disc is used for being connected with a supporting frame of the parabolic antenna; and the coaxial cable penetrates through the wire passing channel and is connected with the vibrator, and the coaxial cable is used for being connected with a signal source. Signals of the feed source assembly are transmitted through a coaxial cable instead of a circular waveguide, so that the diameter of the supporting tube is smaller than that of the circular waveguide. Moreover, the diameter of the supporting tube is far smaller than the diameter of a circular waveguide which has the same frequency and is used for transmitting microwave signals, so that the size of the feed source assembly is greatly reduced, the loss of electrical performance can be reduced, and the weight of the parabolic antenna is reduced.

The invention discloses a photoacoustic sensing unit, an acoustic signal detection device and an acoustic signal detection method, and relates to the technical field of acoustic detection. The lower wrapping layer is arranged on the upper surface of the substrate, and a mounting groove is formed in the lower wrapping layer; the core layer is arranged in the mounting groove, the core layer comprises a straight waveguide and a circular waveguide, and a coupling distance is formed between the straight waveguide and the circular waveguide; the straight waveguide, the circular waveguide and the coupling space jointly form a light field regulation and control area; the exposed area covers the core layer and the lower wrapping layer, the exposed area comprises a groove, and the sensitive medium packaging layer is used for receiving sound pressure signals, generating corresponding deformation and transmitting the deformation to the core layer to cause the structure or state change of the light field regulation and control area, so that the effective refractive index of the circular waveguide is changed, and the sound pressure signal is generated. The change of the effective refractive index causes the drift of the harmonic peak wavelength, and the variation of the sound pressure signal is determined according to the displacement of the harmonic peak wavelength. The sensitivity of sound pressure detection is improved.

The invention discloses a broadband coaxial-circular waveguide output structure of a coaxial gyrotron traveling wave tube, and relates to the field of microwave and millimeter wave passive devices. The structure comprises a coaxial outer conductor, a coaxial inner conductor and a supporting structure arranged between the coaxial outer conductor and the coaxial inner conductor, the supporting structure comprises a plurality of supporting units distributed along the circumference, the widths of the supporting units are increased and then reduced along the axial direction, and the middle sections of the adjacent supporting units are quasi-rectangular waveguide cavities; two cavities with the two ends communicated are dug in the coaxial inner conductor, and the coaxial inner conductor, the supporting unit and the coaxial outer conductor are provided with penetrating through holes used for injecting cooling liquid into the cavity and enabling the cooling liquid to flow out of the other cavity. The supporting structure is adopted to solve the supporting problem of the output part of the coaxial gyrotron traveling wave tube, and has the advantages of wide band and high mode conversion efficiency; in addition, through the arrangement of the through hole and the cavity structure, the cooling of the output part of the coaxial gyrotron traveling wave tube is realized.

This invention provides a Ka / V band dual-frequency conical beam antenna for millimeter-wave detection, comprising an upper square metal structure, a lower square metal structure, a coaxial waveguide, an open circular waveguide, and a feed network. The open circular waveguide is the main radiating part, transitioning from the coaxial waveguide to the open circular waveguide, allowing the open circular waveguide to operate in TM mode to generate a radially symmetrical electric field distribution. By adjusting the size of the open circular waveguide, TM01 and TM02 modes exist within it, respectively generating Ka / V band electromagnetic waves. This invention utilizes a shielded microstrip line to excite the fundamental TEM mode of the coaxial waveguide before transitioning to the TM mode of the circular waveguide, which can suppress other unwanted modes, thereby making the omnidirectional radiation of the antenna more uniform. The coaxial waveguide is a stepped coaxial waveguide with varying radius. The stepped structure of the waveguide inner diameter can achieve good impedance matching. The structure is simple, easy to implement, and has dual-frequency, dual-tilt radiation characteristics.