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49 results about "Log-periodic antenna" patented technology

A log-periodic antenna (LP), also known as a log-periodic array or log-periodic aerial, is a multi-element, directional antenna designed to operate over a wide band of frequencies. It was invented by Dwight Isbell and Raymond DuHamel at the University of Illinois in 1958.

Portable soft oscillator log-periodic antenna

The invention discloses a portable soft oscillator log-periodic antenna, and relates to the technical field of non-frequency-variable antennas. The portable soft oscillator log-periodic antenna comprises an antenna main rod, a folding supporting rod and a winding mechanism, the folding supporting rod is hinged to the antenna main rod, the folding supporting rod is connected with an edge suspension wire arranged at one end, away from the hinged end, of the antenna main rod, the winding mechanism is connected with the folding supporting rod, and the folding supporting rod is connected with the winding mechanism. The winding mechanism is provided with a tightening rope connected with the folding supporting rod, the tightening rope and the side suspension wire apply force rotating in different directions to the folding supporting rod, and the antenna main rod is provided with a soft vibrator connected with the side suspension wire. According to the portable soft oscillator log-periodic antenna, through folding design of the antenna structure, the size of the antenna in a non-working state is effectively reduced, the transportation and installation convenience of the antenna is remarkably improved, and the portable soft oscillator log-periodic antenna has the beneficial effects of being foldable and convenient to transport and install.
Owner:CHENGDU JIYITONG TECH CO LTD

Microstrip patch log periodic antenna (MSPLPA) scaling methodology using non-planar antenna geometries and additive manufacturing

ActiveUS12531333B1Electrically long antennasAntenna earthingsPlanar antennasGround plane
A microstrip patch log periodic antenna (MSPLPA) may include a ground plane, a dielectric material, a printed circuit board comprising a microstrip patches. Each of the microstrip patches may be configured to transmit and / or receive signals. The dielectric material may be disposed between the ground plane and the printed circuit board. Each of the microstrip patches may be frequency scaled.
Owner:ROCKWELL COLLINS INC

Resonant ring and lens structure-based high-gain broadband antenna

The invention provides a high-gain broadband antenna based on a resonant ring and lens structure. A main body part of the antenna comprises a bow-tie dipole broadband log-periodic antenna fed by a parallel strip-shaped microstrip line, a lens, a resonant ring, a supporting back plate and a supporting arm. And the lens structure is formed by processing a Teflon material. The top of the parallel strip-shaped microstrip line feed bow tie dipole broadband log-periodic antenna body part is composed of a microstrip line and three bow tie elements with different sizes, and the bottom of the parallel strip-shaped microstrip line feed bow tie dipole broadband log-periodic antenna body part is composed of three bow tie elements which are transited to the microstrip line and have the same size with the top but are symmetrical in direction, wherein the plane conical shape is symmetrical to a quarter circle. The SMA interface on the back is embedded in the center of the supporting backboard, the lens is located at the end-to-end of the feed source antenna, the structure of the lens is composed of a semi-sphere on the top and two cylinders with different radiuses at the bottom of the middle, and the lens is connected with the supporting backboard through the supporting arm. And the resonant ring is located at the tail end of the log-periodic antenna structure. The working frequency band of the antenna ranges from 7.18 GHz to 12.55 GHz, the gain in the frequency range ranges from 11.1 dBi to 16.0 dBi, and the gain is the highest when the frequency is 10.0 GHz. The antenna has the advantages of simple structure, low cost, wide band, high gain and the like.
Owner:NORTHWEST UNIVERSITY FOR NATIONALITIES

A large bandwidth signal processing device based on SDR

The present application provides a large bandwidth signal processing device based on SDR, belonging to the field of signal technology, wherein the antenna is connected to the data processing board through an SMA interface; the data processing board is connected to the server unit through an optical fiber; the antenna is divided into two groups, one group of antennas is two identical logarithmic periodic antennas; the other group of antennas is two horn antennas with constant gain characteristics; the data processing board includes FPGA and DSP; multiple GTH high-speed interfaces are set between FPGA and DSP; FPGA has built-in ADC input and DAC output; the server unit includes a server, a network card, a CPU and a storage hard disk; the data processing board is connected to the server through an optical fiber; the server has a network card inserted; the network card is connected to the CPU through a PCLe bus; the CPU and the storage hard disk are connected through a PCLe bus. The present application directly implements RF sampling, does not require a down-conversion circuit, and greatly reduces the complexity of the device.
Owner:AIR FORCE EARLY WARNING ACADEMY

Logarithmic periodic antenna

1. Name of the design product: Log-periodic antenna. 2. Use of the design product: As a component for transmitting or receiving electromagnetic waves in radio equipment. 3. Design key points of the design product: Lies in the shape. 4. Picture or photograph that best shows the design key points: Perspective view 1.
Owner:SHENZHEN CITY FEIMIN TECH CO LTD

Log-periodic antenna and ultra-wideband dual-polarized low-profile conformal array antenna

The invention discloses a log-periodic antenna and an ultra-wide-band dual-polarization low-profile conformal array antenna, and belongs to the technical field of design and manufacturing of ultra-wide-band antennas. The array element is formed by compounding and nesting two types of antennas including a miniaturized log-periodic antenna and a Vivaldi antenna, and the structure is multiplexed. According to the provided miniaturized log-periodic antenna, the broadband miniaturized conformal design is realized through composite loading methods such as array top loading, partial array bending, partial array loading dielectric blocks and the like. On the basis, the invention provides a design method for forming the dual-polarized antenna by nesting a Vivaldi antenna and a log-periodic antenna. A Vivaldi antenna is subjected to left and right block design, a radiation slot and an excitation slot are formed through splicing, and an assembly line of a log-periodic antenna is deployed on a left sector plate and a right sector plate of the Vivaldi antenna. According to the dual-polarization array forming mode, large-curvature conformality of the pitching surface is considered, and pitching surface wide-beam coverage and azimuth surface wide-angle scanning application can be achieved.
Owner:THE 54TH RESEARCH INSTITUTE OF CHINA ELECTRONICS TECHNOLOGY GROUP CORPORATION

Circularly polarized log-periodic antenna based on rotation of radiating dipoles

The application discloses a circularly polarized logarithmic-periodic antenna based on rotation of radiating oscillators, and belongs to the technical field of antenna engineering, and aims at solving the problem of how to design a circularly polarized logarithmic-periodic antenna with wide bandwidth, low profile and simple structure. The application forms corresponding circularly polarized characteristics by rotating a plurality of groups of radiating oscillators by a certain angle with parallel assembly lines as the shaft. The antenna only has a plurality of radiating oscillators which change according to the logarithmic-periodic antenna rule, and does not have a main oscillator and a sub-oscillator, so that the structure is simpler and easier to realize. Meanwhile, the circularly polarized effect is formed by rotating the radiating oscillators to a certain phase and the phase difference between the electromagnetic waves of each oscillator and the zero point of the antenna, so that the logarithmic-periodic antenna can obtain good impedance bandwidth and 3dB axial ratio bandwidth in the working frequency band.
Owner:ANHUI UNIV

Log-periodic antenna linear array design method considering grating lobe suppression and application

The application discloses a log-periodic antenna linear array design method considering grating lobe suppression, and comprises the following steps: acquiring a first direction function of a main lobe direction of a uniform linear array composed of a plurality of point source antenna units changing with a feed phase; acquiring a second direction function of a main lobe direction of the uniform linear array composed of a plurality of antenna units under the influence of a beam width of the antenna units; constructing a normalized direction function of the linear array according to the first direction function and the second direction function; obtaining antenna array direction patterns under different intervals of the antenna units according to the normalized direction function by controlling the intervals between the antenna units, so as to acquire an interval range of the antenna units without grating lobes; and constructing a linear array of a plurality of linearly arranged antenna units according to the interval range. The method can solve the problem that the traditional antenna array uses the mode of changing the intervals, feed amplitudes and phases of the antenna units to control the side lobe level, thereby increasing the complexity and cost of the feed.
Owner:NAVAL UNIV OF ENG PLA

Log-periodic antenna with telescopic device

The present invention relates to the field of antenna technology, specifically a logarithmic periodic antenna with a telescopic device, comprising a fixed rod, a support rod and a vibrator, the support rod being mounted on the telescopic head of the fixed rod via a rotating shaft, and the support rod being able to switch to a working state perpendicular to the fixed rod or a coaxial storage state as the telescopic head is raised and lowered; the vibrator is distributed on both sides of the support rod in a logarithmic periodic arrangement, and the vibrator is composed of a plurality of nested telescopic joints, wherein a limit rod and a bottom support with a slide groove are provided in the telescopic joint, and telescopic extension is achieved by sliding cooperation between the slide groove and the limit rod, and when fully extended, the telescopic joint is rotated and fixed by an elastic self-locking mechanism; the synchronous control device also includes a side seat mounted on the support rod, a driving guide rail rotatably mounted on the side seat, and a control slide mounted through the driving guide rail, the control slide being able to be connected to and pushed by the compression head on the top of the vibrator, so as to achieve the purpose of improving the portability and deployment stability of the antenna.
Owner:TAIXING DONGSHENG ELECTRONICS EQUIP FACTORY

Log-periodic antenna with reflection-band-notch-free absorption characteristic

The invention provides a log-periodic antenna with a non-reflection band notch absorption characteristic. The invention relates to the field of antenna design. The antenna comprises a dielectric substrate (1), a log-periodic antenna (2), a resistance loading unit (3), a tail end resistance loading structure (4) and a feed transition structure (5). The resistance loading unit (3) is composed of an oscillator (31), a resistor (32) and an assembly line (23) of a log-periodic antenna, and a single or multiple non-reflection notch bands are flexibly achieved in an energy absorption rather than reflection mode. The tail end resistance loading structure (4) is used for absorbing non-radiation low-frequency components, and therefore the full-band reflection-free characteristic is achieved. The antenna has the advantages of being simple in structure, wide in working frequency band, free of reflection in the full frequency band, capable of flexibly adjusting the notch frequency band and the like, nonlinear distortion caused by echo reflection is reduced, and the antenna has application value in a wireless communication system.
Owner:SOUTHEAST UNIV

A metallized high power log periodic antenna element, array

The application relates to a metalized high-power logarithmic periodic antenna unit and array, and belongs to the technical field of microwave antennas. The antenna unit comprises a feeding coaxial probe, a feeding connection copper block, a metal feeding line and a metal logarithmic periodic dipole structure; the antenna as a whole adopts a full-metal structure without a dielectric plate, and the feeding mode adopts the metal feeding line taking air as the medium, so that the heat dissipation capacity and power capacity of the antenna are improved; the lengths of the antenna dipoles gradually increase from high to low, the dipole arms are folded inwards by 45 degrees with the set line as the central axis in the vertical plane, finally all the dipoles are located on two mutually perpendicular planes, and on the basis of the bottom several groups of dipole arms, the dipole arms are further bent by 90 degrees twice in the vertical direction to form C-shaped dipole arms; the structure effectively reduces the transverse size of the antenna unit, the coupling current between the array elements in the antenna array can be utilized to expand the antenna bandwidth to the low frequency. The application has the advantages of large antenna power capacity, small antenna unit and the like.
Owner:XIAN YIDING INTELLIGENT TECH CO LTD

Miniaturized ultra-wideband conformal antenna and array

The utility model belongs to the technical field of antennas, and particularly discloses a miniaturized ultra-wideband conformal antenna and array, comprising an outer radiation layer, a base layer, an inner radiation layer, a support layer and a conformal mounting layer which are sequentially stacked and connected, a low-frequency oscillator of the log-periodic antenna structure is bent; and a feed cable is accommodated in the supporting layer and is connected with the log-periodic antenna structures in the outer radiation layer and the inner radiation layer. The antenna has the advantages of being small in size, wide in frequency band and capable of being well installed on the surface of an aircraft carrier in a conformal mode.
Owner:HUBEI SANJIANG SPACE XIANFENG ELECTRONICS&INFORMATION CO LTD

A retractable log-periodic antenna

This invention discloses a deployable log-periodic antenna, relating to the field of antenna technology. It includes an antenna body, which is mounted on the lower end of a UAV. The antenna body comprises an upper connecting plate, a lower connecting plate, a fixing rod, a vertical travel electronic lock, a vertical lifting spring assembly, a pulley, a connecting wire, a joint, a connecting rod, and a first vibrator winding device. A lower connecting plate is located at the lower end of the upper connecting plate, and a fixing rod is located at the lower end of the lower connecting plate. Vertical travel electronic locks are installed between the upper and lower connecting plates and between the lower connecting plate and the fixing rod. The beneficial effects of this invention, employing a high-rigidity, highly deployable log-periodic antenna, are self-deploying, large in size, and have low areal density.
Owner:THE 54TH RESEARCH INSTITUTE OF CHINA ELECTRONICS TECHNOLOGY GROUP CORPORATION

Ultra-wideband linear polarization feed source antenna

The invention provides an ultra-wideband linear polarization feed source antenna. The ultra-wideband linear polarization feed source antenna comprises a bottom plate and an antenna assembly arranged above the bottom plate, wherein the antenna assembly comprises a feed coaxial line and two log-periodic antennas, and the two log-periodic antennas are arranged on the two sides of the feed coaxial line respectively; and the two log-periodic antennas are connected in parallel through the feed coaxial line. The problems that in an existing UWB wireless communication system, the impedance coefficient and the gain value of an ultra wide band antenna are unstable, and the beam width of the H face and the beam width of the E face are greatly different can be solved.
Owner:ZHONGKE XINGTU TIANCHEN SKY RESEARCH INSTITUTE (XIAMEN) CO LTD

Log-periodic antenna interference hardware suppression method based on dynamic adjustment scale factor, storage medium and equipment

The invention discloses a log-periodic antenna interference hardware suppression method based on a dynamic adjustment scale factor, a storage medium and equipment. The method comprises the following steps: S1, obtaining a feasible region of the scale factor and an interval factor by using a gain and an isoline between the scale factor and the interval factor; s2, in the feasible region, taking the minimization of the set line length as an objective function, and solving an optimal combination of a scaling factor and an interval factor; s3, calculating the length of any oscillator, the frequency corresponding to the oscillator and the bandwidth controlled by the oscillator; s4, introducing a positioning oscillator, and positioning the oscillator corresponding to the target suppression frequency band; and S5, dynamically adjusting a scaling factor according to a proportional relation between the bandwidth controlled by the positioning oscillator and the bandwidth of the target suppression frequency band, and removing the corresponding oscillator according to the local optimization value of the target suppression frequency band. The core parameters of the antenna are determined through gain isoline constraint and assembly line length minimization, and fine suppression of an interference frequency band is realized in combination with dynamic scale factor adjustment and an adjacent oscillator fine tuning technology.
Owner:STATE GRID JIANGSU ELECTRIC POWER CO XUZHOU POWER SUPPLY CO

Simulation test method and system for radiation sensitivity of electric field

The invention provides a simulation test method and system for radiation sensitivity of an electric field. The method comprises the following steps: acquiring target field intensity of an interference source and simulation parameters of equipment to be tested; constructing a log-periodic antenna model according to the target field intensity, wherein the log-periodic antenna model is a simulation model of a non-frequency-varying broadband antenna; constructing an equipment simulation model of the to-be-tested equipment according to the simulation parameters; importing the log-periodic antenna model and the equipment simulation model into a preset simulation test environment; and in the simulation test environment, performing an electric field radiation sensitivity simulation test on the equipment simulation model based on a preset interference mode. According to the application, the antenna model is established as an interference source to apply interference to the tested equipment, so that the simulation test of the electric field radiation sensitivity is carried out, and the simulation test precision and the simulation test comprehensiveness of the electric field radiation sensitivity are improved.
Owner:RADIO & TELEVISION METROLOGY & TESTING CHENGDU CO LTD +2

High-gain antenna

The utility model provides a high-gain antenna, and belongs to the technical field of antennas. The high-gain antenna comprises a reflecting plate; the two log-periodic antennas are symmetrically arranged relative to the middle vertical plane of the reflecting plate, each log-periodic antenna is provided with a plurality of oscillators, and each log-periodic antenna is provided with a first end provided with the shortest oscillator and a second end provided with the longest oscillator; the second end of each log-periodic antenna is connected to the reflecting plate, and the distance between the first ends of the two log-periodic antennas is smaller than the distance between the second ends of the two log-periodic antennas; the power divider is provided with a first input end and two first output ends, and the two first output ends are respectively connected with the two log-periodic antennas; and the connector is provided with a second input end and a second output end, and the second output end is connected with the first input end. The antenna provided by the utility model has high gain and realizes the consistency of beam width.
Owner:JIANGSU HENGXIN TECH CO LTD +1

Dual-frequency directional log-periodic antenna and unmanned aerial vehicle reconnaissance equipment

The utility model provides a double-frequency directional log-periodic antenna and unmanned aerial vehicle reconnaissance equipment. The provided dual-frequency directional log-periodic antenna comprises a coaxial line, one end of the coaxial line is provided with a connector, and the other end of the coaxial line is provided with a feed part; the oscillator unit comprises a first main beam and a second main beam which extend along the length direction of the coaxial line; the first main beam is located between the coaxial line and the second main beam, and the first main beam and the second main beam are respectively connected with the feed part; the first main beam is connected with a plurality of first antenna oscillators, and the second main beam is connected with a plurality of second antenna oscillators; the plurality of first antenna oscillators are arranged at intervals along the length direction of the coaxial line; the first antenna oscillator and the second antenna oscillator are symmetrically arranged about the coaxial line. The working frequency of the dual-frequency directional log-periodic antenna provided by the utility model is 1160MHz-1300MHz and 1559MHz-1610MHz, and the dual-frequency directional log-periodic antenna is installed on unmanned aerial vehicle reconnaissance equipment and can ensure that the unmanned aerial vehicle reconnaissance equipment accurately and timely discovers unmanned aerial vehicle signals.
Owner:EXCELTEK ELECTRONICS KUNSHAN

Log-periodic antenna with supporting structure

The log-periodic antenna with the supporting structure comprises a metal seat, an antenna assembly and the supporting structure, the antenna assembly is provided with radiators and a coaxial cable, the metal seat is provided with a metal bottom plate, one end of each radiator is arranged on two sides of the metal bottom plate and fixedly connected with the metal bottom plate, and the other end of each radiator is fixedly connected with the supporting structure. The coaxial cable penetrates through the metal base to be connected with the other end of the radiator, the supporting structure is arranged in the middle of the radiator and connected with the radiator in a clamping fit mode, and the outer side of the supporting structure is further connected with the coaxial cable in a clamping mode. According to the utility model, the supporting structure is arranged in the radiator in a clamping manner, and the clamping design of the supporting structure replaces a traditional bunching belt, so that the bunching belt does not need to be tensioned manually, and the influence of manual operation errors on the fastening effect is eliminated; the log-periodic antenna with the supporting structure can prevent the spacer block from slipping off during vibration, temperature change or long-term use, so as to solve the problems proposed in the background technology.
Owner:GUANGDONG TIANNUO COMM TECH CO LTD

Broadband log-periodic antenna

The utility model relates to the technical field of antennas, in particular to a broadband log-periodic antenna, which comprises two main rods and a plurality of fixing frames used for fixing the two main rods. The bottom ends of the two main rods are jointly provided with a fixing base and an angle adjusting structure, and the angle adjusting structure is used for adjusting the angles between the two main rods and the fixing base. The top ends of the two main rods are jointly provided with a feed structure, and the feed structure is covered with a waterproof structure. A radio frequency connector is installed at the bottom end of one main rod, one main rod is hollow and is provided with a cable in a penetrating mode, one end of the cable is connected to the feed structure, and the other end of the cable is connected to the radio frequency connector; a plurality of groups of vibrator pairs are sequentially mounted on the outer sides of the two main rods at intervals in the length direction, and the lengths of the plurality of groups of vibrator pairs are gradually increased from the bottom ends to the top ends of the main rods. According to the utility model, the technical problems of poor adjustability of the mounting angle and insufficient structural durability of the conventional antenna are solved, and the antenna can be ensured to continuously and efficiently operate in various extreme environments.
Owner:广东健博通科技股份有限公司

Microstrip log-periodic antenna and radio transceiver

The application discloses a microstrip logarithmic periodic antenna and a radio transceiver device, and the antenna comprises a radiation oscillator, a dielectric substrate, a metal ring, a ring carrier and a feed port; the radiation oscillator is arranged in a logarithmic periodic antenna array and is located on the dielectric substrate; the metal ring corresponds to the logarithmic periodic radiation oscillator one by one; the metal ring is discretely distributed on the surface of the ring carrier; and the metal ring and the radiation oscillator are in position correspondence and have the same number. By adding a plurality of conical ring metals outside the traditional logarithmic periodic antenna, the gain is increased, the sidelobe is reduced, and the logarithmic periodic antenna is better than the traditional logarithmic periodic antenna, and has many advantages such as high gain, high aperture efficiency, low sidelobe and miniaturization.
Owner:ANHUI UNIV

High-performance log-periodic antenna

The utility model discloses a high-performance log-periodic antenna, which relates to the field of electronic communication and comprises a radiation oscillator. The radiation assemblies are symmetrically arranged on the two sides of the radiation oscillator, each radiation assembly comprises multiple groups of radiation arm units which are arranged at intervals in the axial direction of the radiation oscillator, and each radiation arm comprises a first radiation arm which is vertically connected with the radiation oscillator and a second radiation arm which is located at the far end of the first radiation arm and is bent towards the radiation end of the radiation oscillator; the radiation end of the radiation oscillator is provided with an array coupling end. By designing the bent second radiation arm on the radiation oscillator, the distortion of an antenna radiation pattern caused by a conformal equipment metal shell plate is greatly reduced, and meanwhile, the second radiation arm is beneficial to improving the equivalent radiation electric size of the antenna, the low-frequency working bandwidth of the antenna can be expanded, and the size miniaturization of the antenna is realized.
Owner:WUHAN JINGDUN INFORMATION TECH CO LTD

Retractable log-periodic antenna

The invention discloses a foldable log-periodic antenna, and relates to the technical field of antennas, the foldable log-periodic antenna comprises an antenna main body, and the lower end of an unmanned aerial vehicle is provided with the antenna main body; the antenna body comprises an upper connecting plate, a lower connecting plate, a fixing rod, a vertical stroke electronic lock, a vertical pull-up spring set, a pulley, a connecting wire, a joint, a connecting rod and a first oscillator winder, the lower connecting plate is arranged at the lower end of the upper connecting plate, and the fixing rod is arranged at the lower end of the lower connecting plate. And vertical stroke electronic locks are arranged between the upper connecting plate and the lower connecting plate and between the lower connecting plate and the fixing rod. After the technical scheme is adopted, the antenna has the beneficial effects that the antenna has the advantages of self-folding and unfolding, large size and low surface density by adopting the high-rigidity and high-folding and unfolding log-periodic antenna.
Owner:THE 54TH RESEARCH INSTITUTE OF CHINA ELECTRONICS TECHNOLOGY GROUP CORPORATION

A miniaturized log-periodic antenna and its assembly and design methods

This invention discloses a miniaturized log-periodic antenna and its assembly and design methods, belonging to the field of communication antenna technology. The antenna includes a dielectric substrate, a semi-steel cable, an adapter plate, and a copper layer; the copper layer is disposed on the front and back sides of the dielectric substrate; an adapter plate is disposed at one end of the dielectric substrate; the outer shell of the semi-steel cable is welded to the copper layer at the center line of the back side of the dielectric substrate, and the inner core of the semi-steel cable is bent upwards through the side of the dielectric substrate without the adapter plate and then welded to the copper layer on the front side of the dielectric substrate; the antenna operates in the frequency band of 150MHz–400MHz, with a VSWR ≤2, and uses linear polarization. This invention addresses the performance shortcomings of traditional antennas in this frequency band by optimizing the structure of the vibrator and improving the feeding method, enabling it to cover the target frequency band while meeting the lightweight and miniaturized usage requirements of different scenarios.
Owner:AVIC FORSTAR S&T CO LTD

Optimized log-periodic tooth antenna with multi-output and wideband frequency capture

This disclosure related to apparatus and methods of use for a log periodic antenna having a first arm and a second arm positioned opposite a center from the first arm. Each arm is divided into a plurality of zones, and each zone is configured to harvest signals of a specific frequency range. The plurality of zones collectively harvests signals spanning across a frequency range, the frequency range being at least one of a variety of ranges. The antenna also has a parallel connection system including a plurality of connections, wherein the plurality of connections includes non-crossing connections between zones of the first arm and zones of the second arm configured to harvest signals of a same frequency range. Also, the antenna has a plurality of multi-output channels, each output channel coupled to one of the non-crossing connections, and each multi-output channel having multiple feeding points, each capable of accommodating a receiver operating over multiple frequencies.
Owner:QATAR FOUND FOR EDUCATION SCI & COMMUNITY DEV