56results about How to "Achieve widening" patented technology

The invention discloses a millimeter-wave fan beam cylindrical Luneberg lens antenna based on a metal perturbation structure. The antenna achieves a pitch beam width reaching 104 degree and azimuth plane +/- 60 degree scanning. The antenna comprises a cylindrical Luneberg lens located between an upper metal flat plate (1) and a lower metal flat plate (2); an arc feed source array (3) located on the focal line of the cylindrical Luneberg lens; and the metal perturbation structure (5) arranged on the radiating aperture of the lens circumferentially. The cylindrical Luneberg lens comprises a cylindrical filling dielectric sheet (4). The filling dielectric sheet uses a low-loss microwave substrate as a substrate material and is divided into five layers according to a concentric circle structure from inside to outside. Respective layers have through-holes with different densities. The through-holes are filled with air. The antenna is light in weight and easy to process, greatly increases the pitch surface beam width, realizes a wide beam scanning range in the horizontal plane so as to be better applied to a multi-beam directional communication and beam scanning antenna, especially the millimeter wave high-frequency band and applications requiring axial grouping.

The invention provides a system and a method for inhibiting a stimulated Brillouin scattering effect in a high-power narrow-linewidth optical fiber laser amplifier. According to the system, single-frequency laser output by a single-frequency laser device in a high-power narrow-linewidth optical fiber laser amplifier is subjected to phase modulation, wherein the adopted phase modulation signal is phi f (t), phi f (t) is rem (phi (t)/2pi), single-frequency laser spectrum broadening is achieved, and the purpose of restraining the stimulated Brillouin scattering effect is achieved. Compared with the existing white noise signal modulation and pseudo-random phase encoding modulation, the method of the invention has the following characteristics that efficient stimulated Brillouin scattering suppression can be achieved, and theoretical basis and technical support are provided for further power improvement of a high-power and narrow-linewidth optical fiber laser system.

The invention discloses a low-profile LTCC millimeter wave dual-polarization array antenna, comprising: electromagnetic waves input from a port 1 are transmitted in an intermediate layer power split structure, are coupled into an upper layer power split structure through a slot 3, are coupled into an antenna element through the slot 1, and polarization in a direction 1 is generated; The electromagnetic wave inputted from the port 2 is transmitted in the lower power division structure, coupled into the middle power division structure through the slot 5, coupled into the upper power division structure through the slot 4, coupled into the antenna unit through the slot 2, and polarized in the direction 2; As that electromagnetic wave is polarize in the receiving direction 1, the electromagnetic energy enter the upper work division structure through the slit 1 and enters the middle work division structure through the slit 3; As that electromagnetic wave is polarize in the receiving direction 2, the electromagnetic energy enter the upper power split structure through the slot 2, couples into the middle layer power split structure through the slot 4, and couples into the lower layer powersplit structure through the slot 5. The invention realizes antenna high gain, wide frequency band and high isolation of two ports.

The invention provides an ultra-wideband underwater acoustic transducer. The ultra-wideband underwater acoustic transducer comprises a shell and an underwater acoustic transducer body installed in the shell; the underwater acoustic transducer body comprises five piezoelectric ceramic circular tubes sequentially arranged; adjacent piezoelectric ceramic circular tubes are isolated through plastic foam; after being mutually compressed, the five piezoelectric ceramic circular tubes and the plastic foam are fixed in the shell; the vibration mode of the transducer is expanded from inside to outside under the stimulation of an external voltage signal; therefore, the transducer performs radial vibration and outwardly radiates acoustic wave energy; a difference value between a set of adjacent peak valleys on a frequency response curve is reduced by adjusting the longitudinal arrangement distance of the five piezoelectric ceramic circular tubes and controlling a transmitting voltage response value at a resonant frequency; namely, fluctuation of transmitting voltage response is reduced within a working band; the transmitting voltage response amplitude of the transducer at non-resonant frequency is nearly not decreased; therefore, broadening of the working band of the transducer is realized; the integral structure and a manufacturing process are simple; and the cost is low.

The invention discloses a medium-small span old bridge reinforcement and jointing-widening structure. The medium-small span old bridge reinforcement and jointing-widening structure comprises a reinforcement structure located below an old bridge and a jointing-widening structure located at at least one side of the old bridge. The reinforcement structure comprises a pair of reinforcement pile foundations arranged at the two sides of the old bridge span. Steel plates are erected between the pair of reinforcement pile foundations along the bridge bottom face to form a reinforcement bridge floor in a jointed mode. A hollow cavity is formed between the reinforcement bridge floor and the bottom face of the old bridge and filled with concrete. The jointing-widening structure comprises a pair of jointing-widening pile foundations arranged at the two ends of the old bridge span and at least one sides of the reinforcement pile foundations correspondingly. Steel plates are erected between the pair of jointing-widening pile foundations to form a jointing-widening bridge floor in a jointed mode, and the jointing-widening bridge floor is adjacent to the reinforcement bridge floor and identical to the reinforcement bridge floor in radian. A reinforcement plate is arranged on the jointing-widening bridge floor. A hollow cavity is formed between the reinforcement plate and the jointing-widening bridge floor and filled with concrete. Backfill is arranged on the jointing-widening bridge floor and reinforcement plate to be flush with the old bridge floor. According to the medium-small span old bridge reinforcement and jointing-widening structure, the existing bridge is reinforced and widened through the reinforcement structure and the jointing-widening structure, and the problem caused by dismantling and rebuilding of the old bride is avoided.

The invention discloses a multi-frequency broadband antenna based on a broadband antenna and trapped wave structure. The antenna consists of a radiator (1), a first U-shaped gap (2), a second U-shaped gap (3), a third U-shaped gap (4), a floor (5), a feeder (6) and a dielectric slab (10), wherein the radiator (1) and the feeder (6) are applied to one surface of the dielectric slab (10) by a copper applying process; the floor (5) is applied to the other surface of the dielectric slab (10) by a copper applying process; the radiator (1) and the feeder (6) are applied together; and the first U-shaped gap (2), the second U-shaped gap (3) and the third U-shaped gap (4) are etched on the radiator (1) by photoetching. By adopting the three U-shaped gaps, multi-frequency resonance of the antenna is realized, and the multi-frequency antenna can operate within the frequency ranges from 2.15GHz to 2.8GHz, from 3.15GHz to 3.85GHz, from 4.65GHz to 6.1GHz and from 6.6GHz to 8.0GHz, the central resonance frequency of the antenna is adjustable, the operating frequency of the multi-frequency antenna can be adjusted conveniently, and the shortages that the structure is complex and the resonance point cannot be easily adjusted in the conventional multi-frequency antenna design are overcome.

The invention discloses a four-branch multi-frequency cylindrical dipole antenna which comprises a shell, a first branch, a second branch, a third branch, a fourth branch, a copper-exposing area and a feed source. The four branches, the copper-exposing area and the feed source are coated in the shell, and the four branches are respectively connected with circuits. The four-branch multi-frequency cylindrical dipole antenna is characterized in that the first branch and the second branch are symmetrically and abreast arranged at the lower sides of the third branch and the fourth branch, the four branches are penetrated by the feed source and the copper-exposing area and integrated, the feed source is communicated with the circuits on the third branch and the fourth branch, the copper-exposing area is communicated with the circuits on the first branch and the second branch, the copper-exposing area of a hollow rod body is spliced in the centers of the first branch and the second branch and connected with the top end of the first branch and the lower end of the second branch, and the feed source is spliced in the copper-exposing area for receiving an external radio signal. The antenna structure of the four-branch multi-frequency cylindrical dipole antenna also has the advantages of small size, remarkable quakeproof effect, and the like as well as excellent wireless communication performance.

The invention relates to a trans-impedance compensation type visible light communication receiver comprising a visible light detector for converting an inputted visible light signal into a current signal, a trans-impedance pre amplifier for converting the current signal outputted by the visible light detector into a voltage signal, a limiting amplifier for amplifying the voltage signal outputted by the trans-impedance pre amplifier to be at a voltage level needed by a digital processing unit, and an output buffer stage unit for providing a voltage signal at a digital voltage level. The input terminal of the trans-impedance pre amplifier is connected to the output terminal of the trans-impedance pre amplifier by a feedback resistor and a feedback inductor; and the output of the output buffer stage unit forms an output terminal. According to the invention, with a standard CMOS process, broadening of the bandwidth of the visible light receiver is realized and thus the visible light communication system takes an important step towards integration. The optical communication system and the semiconductor communication chip industry are combined; and the visible light communication chip enables the new vitality to be injected into the communication chip industry.

The invention discloses a widening device of a high-power laser beam and a method thereof. The device comprises a continuous laser, a sector reflection focusing lens, a deflection-type oscillating mirror, a high-speed motor and a computer. One side of the deflection-type oscillating mirror is connected with a rotation shaft of the high-speed motor. The high-speed motor is connected with the computer. The deflection-type oscillating mirror and the sector reflection focusing lens are placed oppositely. The laser beams emitted by the continuous laser are homocentric with a turning center O of thesector reflection focusing lens at a reflecting point C of the deflection-type oscillating mirror. The method causes the continuous laser beam output by the continuous laser to form continuous scanning beams in the sector region with a certain scanning angle alpha after being reflected by the deflection-type oscillating mirror rotating at high speed, wherein the scanning beams form continuous arcscanning focusing light bands on the surface of the processed work piece after being reflected and focused by the sector reflection focusing lens. Compared with the prior art, the device can widen the high-power laser beam in a wider range (20-500mm) and the widened width is continuously controllable.

The invention discloses a novel gyrotron traveling wave tube input coupler, and belongs to the technical field of microwave and millimeter-wave devices. The novel gyrotron traveling wave tube input coupler comprises a coaxial structure, a cut-off circular waveguide, an output circular waveguide and a rectangular input waveguide, wherein the cut-off circular waveguide and the output circular waveguide are arranged at two ends of the coaxial structure respectively; the rectangular input waveguide is arranged on the side surface of the coaxial structure; a plurality of coupling gaps are arranged in an inner conductor of the coaxial structure; and a short-circuit branch rectangular waveguide is arranged on an E surface of the rectangular input waveguide. The short-circuit branch waveguide is arranged on the E surface of the rectangular input waveguide on the basis of a traditional gyrotron traveling wave tube. Reflection of the input coupler can be effectively offset by reasonably designing the position and structure parameters of the short-circuit branch waveguide; and the transmission efficiency of a high-frequency end is improved, so that the input bandwidth is effectively expanded.

The invention provides a method for adjusting a carbon nitride energy band structure. The method comprises the following steps of: performing heat treatment by adopting different boron sources and carbon nitride, and controlling the temperature of the heat treatment to realize widening or narrowing of the carbon nitride energy band structure. According to the invention, continuous controllable widening or narrowing of a carbon nitride energy band structure is realized, and through modification of carbon nitride, valence band potential is increased, water oxidation activity is improved, and proper conduction band potential is reserved to drive oxygen to be reduced to generate hydrogen peroxide; the regulation and control method provided by the invention realizes continuous controllable regulation of the carbon nitride energy band structure, and can be used for synthesizing carbon nitride with a specific energy band structure; the prepared carbon nitride can be used for photocatalytic synthesis of hydrogen peroxide under the condition of not adding a sacrificial agent, and shows relatively high photocatalytic activity due to relatively narrow band gap, reasonable valence band and conduction potential; and the preparation method is simple, easy to operate, high in expansibility, low in cost and easy to amplify.

The invention belongs to the technical field of radar antennae, and provides a broadband non-contact coaxial rotary joint and a radar antennae, the rotary joint comprises a stator shell, a rotor shell, a stator inner conductor, a rotor inner conductor and a transition inner conductor, the stator inner conductor and the transition inner conductor are coaxially installed in the stator shell, the rotor inner conductor is coaxially arranged in the rotor shell, the rotor shell is rotatably connected with the stator shell, and two ends of the transition inner conductor respectively form a non-contact coupling circuit with the stator inner conductor and the rotor inner conductor. Based on the defects of non-contact type and contact type radio frequency rotary joints in the prior art, the problem that a traditional non-contact type rotary joint is small in signal transmission frequency band range is effectively solved, and the rotary joint can be used for adapting to the rotation direction of a broadband antenna in real time under the condition that signal transmission is uninterrupted, the electrical performance consistency of signal transmission in the rotation process of the antenna is improved, and the antenna can adapt to each frequency band of X-Ka.

The invention belongs to the field of optical pulse signal processing, particularly relates to an optical pulse broadening method, aims to solve the problem of narrow linewidth spectrum optical pulse broadening. The optical pulse broadening method is characterized in that optical pulses are subjected to uniform delay and proportional reflection/transmission through multi-stage optical paths, then multi-path reflected optical pulse signals are combined to realize optical pulse broadening, and a photoelectric detector module is used for carrying out envelope detection to obtain an electric pulse signal. The optical pulses are transmitted to enter transflective mirrors with specific reflectivity, the distances between the adjacent transflective mirrors are equal, the corresponding delays are further equal, the optical pulse is transmitted to enter the optical coupling module for the same distance after being reflected each time, multiple paths of optical pulses are arranged and combined on a time domain after being coupled to realize optical pulse broadening, and the electric pulse signal is obtained through the photoelectric detection module. The optical pulse broadening method is further suitable for broadening wide spectrum pulse signals.

The invention discloses a basic unit and an analog signal processing space phase shifter constructed based on the basic unit. The basic unit comprises n*n basic units, the n*n basic units are periodically arranged, each unit comprises a five-layer metal structure and a four-layer dielectric structure, electromagnetic signals with different frequencies generate different group delays through the elaborately designed structure, and then analog signal processing is achieved. The space phase shifter with the stepped group delay response has a pulse position modulation function, and the spatial phase shifter with the linear group delay response has a pulse broadening function. The method is simple in principle, low in manufacturing cost and wide in application prospect.

The invention discloses a tri-branch multi-frequency plane dipole antenna, comprising a shell, a first branch, a second branch, a third branch, a copper exposure zone and a feed source, wherein the first branch, the second branch and the third branch are respectively connected with corresponding circuits. In particular, the first branch, the second branch and the third branch are laminated structures connected with each other in the same one plane, wherein the first branch and the second branch are symmetrically arranged at both sides of the third branch; the first branch and the second branch are jointly combined far away from one end of the third branch and are connected with the copper exposure zone at the lower end of a public area into a whole; the feed source is inserted between the first branch and the second branch and communicated with the third branch at the upper end of the copper exposure zone; and the third branch is a gradually widening structure back on to the copper exposure zone. The plane dipole antenna structure also has the advantages of small size, remarkable anti-vibration effect and excellent wireless communication performance; and therefore, the tri-branch multi-frequency plane dipole antenna can be widely applicable to 3G (The 3rd Generation Telecommunication) wireless terminal products of a CDMA2000 (Code Division Multiple Access 2000) system, a TD-SCDMA (Time Division-Synchronization Code Division Multiple Access) system, a WCDMA (Wideband Code Division Multiple Access) system, and the like.

The invention discloses a broadband sleeve antenna for a portable terminal device, in combination with actual portable terminal device application, a broadband monopole sleeve antenna design based ona terminal structure body is provided under a condition that antenna structure size is limited, and an antenna band covers 225-678 MHz. In the design, conventional bandwidth broadening methods of adding lossy devices, such as a magnet ring, are discarded, and the design is realized through a sleeve structure and a helix loading mode, meanwhile, a spiral spring is designed to be roundabout so as torealize reduction of size, and a plurality of spiral radiators are connected in parallel under different thread pitches so as to realize broad band, thus, functions of a plurality of antennae can berealized by one antenna.

The invention discloses a heterogeneous material structured multilayer film wave absorber and a manufacturing method thereof. A structured multilayer film comprises a silicon substrate, an Ag film, aSiO2 film and a SiNx film which are sequentially stacked from bottom to top, the whole structured multilayer film is a micro-pyramid structure array. During preparation, a single-point diamond turningtechnology is adopted to directly complete forming of the micro-pyramid structure in the heterogeneous material multi-layer thin film. The heterogeneous material structured multilayer film wave absorber provided by the invention shows obvious wave absorbing characteristics on visible light waves and infrared band light waves; the heterogeneous material structured multilayer film wave absorber containing the metal-medium can realize absorption of electromagnetic wave energy, is low in preparation cost and high in efficiency, and has important practical value in the fields of photovoltaics andinvisibility.