75 results about "Traveling-wave antenna" patented technology

A flat strip-like radiator is angled along the width of the strip to form radiating arms of predetermined length and angles to radiate a design radiation patter. The flat strip is secured to a ground plane such that the flat strip is perpendicular to the ground plane.

A vertically polarized traveling wave antenna is omnidirectional, bottom-mounted, and bottom-fed. A robust center coax provides a self-supporting mechanical structure. Multiple dipoles are capacitively coupled to the coax in quads, with a first two dipoles placed on opposite sides of the center coax and spaced by a quarter wavelength along the coax from the second two, which couple at right angles to the first two. This matched-layer spacing cancels the reactive components of the impedances of the dipoles. Beam tilt is readily incorporated over a wide range by adjusting layer spacing to add phase taper. All dipoles are oriented parallel to the coax axis, with opposite “hot” (center coupled) dipole elements oriented oppositely to each other. A radiated signal thus has rotating phase, when viewed from above, but is vertically polarized at each azimuth. A lightweight radome, provided for weather protection, is not needed for structural integrity.

The invention discloses a repeater antenna for use in point-to-point applications in telecommunications systems in the microwave range, intended for connecting transmissions from a first radio unit at a first site to a second radio unit at a second site. The repeater antenna is essentially plane, and is designed as a traveling wave antenna with at least a first and a second antenna beam, so that the first beam can be used for transmissions to and from said first radio unit, and the second beam can be used for transmissions to and from said second radio unit.

A broadband/multiband circular array antenna is disclosed. One embodiment comprises a circular directional array antenna comprising a driven omnidirectional traveling-wave antenna element coupled to a transceiver via a feed and a plurality of surface-waveguide elements symmetrically positioned about and spaced from the driven omnidirectional traveling-wave antenna element. Each surface-waveguide element receives a control signal configured to selectively alter its waveguide characteristics to electronically direct a beam to/from the array. The array provides a directionally controllable antenna beam with broadband/multiband frequency performance in a low profile design that is both economical and practical to produce and maintain.

A planar broadband beam-steering phased array antenna with approximately 10:1 bandwidth is comprised of planar broadband traveling wave antenna elements positioned parallel to a conducting ground plane and spaced less than 0.5 wavelength at the highest operating frequency and more than 0.01 wavelengths at the lowest operating frequency. Each planar traveling wave antenna element is a planar frequency-independent antenna or planar self-complementary antenna, and is truncated to fit a unit cell of the phased array. Adjacent antenna elements are arranged to be tightly coupled together or connected with each other and spaced less than 0.5 wavelength apart between their centers throughout its operating frequency range. One or more layers of dielectric or magneto-dielectric substrates/superstrates can be added to enhance specific performances.

A dielectric travelling wave antenna (DTWA) using a TEM mode transmission line and variable dielectric substrate.

The invention discloses a left-right hand circular polarization reconstructible micro-strip travelling wave antenna array, and belongs to the antenna technical field; the left-right hand circular polarization reconstructible micro-strip travelling wave antenna array uses a conventional square corner cut circular polarization micro-strip antenna structure as a base, considers impedance match characteristics between array elements, employs a cascade mode to connected the sub-array elements, thus forming the micro-strip travelling wave antenna array, and further using a switch control feed network feed mode to reach a left-right hand circular polarization reconstructible purpose. The micro-strip travelling wave antenna array, a Wilkinson power divider and the circular polarization technology are combined, so low profile, low cost and low cross polarization characteristics of a tradition circular polarization micro-strip paster antenna can be inherited, and broadband and high gain advantages can be added; the left-right hand circular polarization reconstructible micro-strip travelling wave antenna array is applied to the radar and communication systems like an aircraft, a ship, and a vehicle device.

Techniques for implementing series-fed antenna arrays with a variable dielectric waveguide. In one implementation, coupling elements with optional controlled phase shifters are placed adjacent each radiating element of the array. To avoid frequency sensitivity of the resulting array, one or more waveguides have a variable propagation constant. The variable waveguide may use certain materials exhibiting this phenomenon, or may have configurable gaps between layers. Plated-through holes and pins can control the gaps; and/or a 2-D circular or a rectangular travelling wave array of scattering elements can be used as well.

The invention relates to a circular polarized antenna. A metal waveguide tube of the antenna is the hollow single-ridge metal waveguide tube with the cross section in a shape like the Chinese character 'ao'. One end of the metal waveguide tube is the input end, and the other end of the metal waveguide tube is the output end. The metal walls of upward-protruded narrow sides on the two sides of the metal waveguide tube are respectively provided with an oblique slot. The oblique slots on the two sides of the metal waveguide tube are in mirror symmetry. An included angle between each oblique slot and the longitudinal axis of the metal waveguide tube is theta. A straight slot parallel to the central line of the metal waveguide tube is formed in the horizontal tube wall in a groove of the metal waveguide tube. The eccentric distance is formed between the straight slot and the central line of the metal waveguide tube in the length direction. The geometric center of the two oblique slots in mirror symmetry and the geometric center of the straight slot are located in the same cross section of the metal waveguide tube. The circular polarized antenna is simple in structure, easy to machine and light in weight. Compared with CN 200910184962.6, the weight is reduced by about half when the circular polarized antennas form an antenna array. The port of the output end of the metal waveguide tube of the antenna is short-circuited through metal or is connected and matched with a load so that a standing wave antenna array or a traveling wave antenna array can be conveniently obtained.

The invention discloses an antenna for generating radial spreading RF OAM wave beams based on an annular travelling wave antenna. The integral structure of the antenna includes a metal annular cavity, a circular ring slit is formed in one side surface of the cavity, the metal annular cavity is formed by bending a rectangular waveguide, the width of the metal annular cavity serves as the broadside of the rectangular waveguide, the height of the side surface serves as the narrow side of the rectangular waveguide, the slit is arranged in the middle of the narrow side, the perimeter of the metal annular cavity equals the vertical length of the rectangular waveguide, the sidewall of the metal annular cavity is provided with an annular loudspeaker, the annular loudspeaker is composed of two parts in up and down symmetry, a slit is formed at the bottom end of the annular loudspeaker during combination, and the position of the slit corresponds to the circular ring slit in the middle of the narrow side of the annular metal cavity. The antenna structure of the invention is formed by combining a resonant cavity of the rectangular waveguide with the antenna structure of the annular travelling wave antenna, the channel capacity of a direct channel can be improved, the transmission distance is increased, and the transmission efficiency of the communication system is improved.

The invention relates to a single-layer dual-circular polarization cavity backed traveling wave antenna with a filtering function. Most of back cavity filtering antennas are of a multi-cavity structure; although good filtering characteristics can be achieved, the defects of high profile, large size, high cost and the like of the back cavity filtering antennas limit the application of the filteringantennas. According to the invention, the integrated design of the antenna and the filter is carried out in the single-layer single substrate integrated waveguide cavity, and the functions of a band-pass filter and a circularly polarized radiator are realized at the same time. In addition, different ports of the filtering antenna are fed respectively, and the other port is connected with a load to realize left-handed circular polarization radiation and right-handed circular polarization radiation respectively. The filtering antenna has good filtering characteristics, wide bandwidth and high gain, and is simple in structure and easy to process and manufacture.

The invention is a novel solution to circumvent the fundamental gain bandwidth limitations of an antenna of a given size by using a traveling-wave (TW) antenna and strongly coupling it with the mounting platform to enlarge the effective size of the antenna. A preferred form of this invention comprises a conducting ground surface generally curvilinear and conformal to said platform, a broadband TW surface radiator positioned above and spaced apart from said ground surface, an impedance matching structure between the surface radiator and the conducting ground surface, and a reactive impedance matching network positioned on the periphery of said surface radiator.

The invention discloses a wave beam switchable antenna device and a method thereof. The device comprises antennas arranged separately in rows, each antenna unit comprises two travelling wave antenna arrays arranged separately from left to right and used for transmitting and receiving radar high-frequency signals, the lengths of the travelling wave antenna arrays in the left side increase gradually, the lengths of the travelling wave antenna arrays in the right side decrease gradually, the travelling wave antenna arrays in the left side can generate wave beams of different deflection directions to cover a specific range in the left side, and the travelling wave antenna arrays in the right side can generate wave beams of different deflection directions to cover a specific range in the right side. According to the method, the quantity and lengths of the antenna arrays can be determined according to a required coverage range, after the antenna device is arranged, switching of the travelling wave antenna arrays is controlled and directional wave beams in the left and right sides are switched. The device and method can realize switching of multiple wave beams, and have the advantages including simple and compact structure, low needed cost, large spatial coverage range and small size.

A frequency-scan traveling wave antenna receives radio frequency (RF) energy at an input port, passes the energy through a quarter wave transformer to a first radiator element in an array of radiator elements, each pair of radiator elements being connected by a respective delay line. Each radiator element includes an input port of known characteristic impedance connected to an impedance matching section which compensates for that element's radiated power. Each radiator element has an output port with a section of transmission line disposed between a main radiator section of said radiator element and said output port, and impedance matched to the output port. In one embodiment, each delay line includes a plurality of delay line sections, with adjacent delay line sections being mutually perpendicular. In a second embodiment, each delay line includes a plurality of delay line sections disposed in meandering form.

A vertically polarized traveling wave antenna forms peanut-type directional lobes without significant nulls between the lobes. A self-supporting coaxial line feeds quad-dipole bays coupled around the coaxial line, with opposed dipole pairs spaced along the coaxial line. Matched-layer spacing provides substantial cancellation of the reactive components of the loads. Dipoles are oriented parallel to the coaxial line axis, with opposite “hot” (center coupled) elements oppositely oriented. Radiated signals have rotating phase. Changing the spacing within quads from a quarter wavelength or rotating the second dipole pair of each quad away from a right angle causes the antenna to radiate strongly on one axis and weakly at right angles thereto, without the nulls of back-to-back panel antennas.

A radio frequency antenna for radiating electromagnetic energy into a reservoir filled with a target material, the antenna being operatively connected to a feed transmission line. The antenna includes a waveguide, at least one slot formed in the outer waveguide layer, and a sleeve portion enclosing at least a portion of the waveguide. The sleeve portion comprises at least first and second dielectric layers where the permittivity of the second dielectric layer is higher than the permittivity of the first dielectric layer and the first dielectric layer is positioned in closer proximity to the waveguide than the second dielectric layer. When the antenna is inserted into the reservoir, the input impedance of the antenna remains matched to the feed transmission line for a wide range of target materials.

The invention discloses an integrated substrate gap waveguide circularly polarized slot traveling wave array antenna which comprises an upper dielectric plate, a lower dielectric plate and a spacer dielectric plate disposed between the upper dielectric plate and the lower dielectric plate. A first copper cladding layer is printed on an upper surface of the upper dielectric plate, a plurality of slit units spaced apart in a predetermined direction are etched on the first copper cladding layer, and each of the slit units comprises two rectangular slits whose length directions intersect and are not parallel to the predetermined direction, and a feeding microstrip line arranged in the predetermined direction is printed on a lower surface of the upper dielectric plate. Circular metal patches which are periodically arranged are printed on an upper surface of the lower dielectric plate, a second copper cladding layer is printed on a lower surface of the lower dielectric plate, each of the circular metal patches is provided with a metal through hole which passes through the lower dielectric plate, and the metal through hole is connected to the second copper cladding layer. According to theinvention, the disadvantages of complex structure and weak electromagnetic shielding performance of an existing circularly polarized traveling wave antenna can be overcome.