Nec Corporation

Nec C Orporation

Kosuke Tanabe

Akio Kuramoto

Masashi Hirabe

Tsunehisa Marumoto

Hiroyuki Yusa

Jun Qian

Atsushi Ooshima

Nader Zein

Norihiko Ohmuro

Christos Masouros

A wireless communication apparatus performs a first processing for changing the receiving beam in a first direction to determine a first angle for the receiving beam. The wireless communication apparatus performs a second processing for changing the receiving beam in the first direction from the first angle to determine a second angle that is a final angle for the receiving beam.

Wireless communication apparatus and method

A radome () includes a first region (A) and a second region (B) having different radio-wave transmission characteristics from each other, and is configured to form a null pattern in substantially a front direction of an antenna by superimposing a first radio wave that has passed through the first region (A) and a second radio wave that has passed through the second region (B).

Radome and pattern forming method

The present disclosure aims to provide an antenna directivity adjustment apparatus and an antenna directivity adjustment method capable of preventing an antenna gain from being reduced and easily adjusting a direction of an antenna. An antenna directivity adjustment apparatus () includes: a second antenna () that is opposed to a radiation surface () of a first antenna () and receives radio waves output from the first antenna (); and an output unit () that is provided in the second antenna (), converts a first beam width of the received radio waves into a second beam width wider than the first beam width, and outputs the radio waves having the second beam width.

Antenna directivity adjustment apparatus and antenna directivity adjustment method

A mounting unit () securely mounts a radio wave reflection device () on a stable installation place such as a pole (). A reflector unit () holds two reflectors () at a tilt angle of 45&#xb0;, allowing the two reflectors () to be coaxial and rotatable independently of each other. A joint unit () connects the reflector unit () and the mounting unit (). The joint unit () has rotational freedom along two axes (AZ axis and EL axis) orthogonal to each other. A radio wave reflecting device that relays, by reflection, radio communications between a first antenna device and a second antenna device distant from each other is thereby provided.

Radio wave reflection device

A planar antenna according to the present invention includes a plurality of antenna elements arranged thereon and characterized in that two opposite corner parts from among corners of an N-gon (N is an even number equal to or greater than four) are cut out. For example, a planar antenna has a shape in which two opposite corner parts from among four corner parts included in a rectangle () (N=4) are cut out. The planar antenna may be composed by combining a plurality of square antenna units on which a plurality of antenna elements are arranged.

Planar antenna

A reflector device having first and second reflector plates to which a reflective surface is attached, respectively, at a prescribed angle of inclination in relation to an axis of rotation, wherein the first reflector plate () and the second reflector plate are positioned so as to face one another, and the first reflector plate and/or the second reflector plate are/is capable of rotating around the axis of rotation.

Reflector device, communication system using the same and communication method using the same

An antenna device includes a reflector which forms an offset antenna with a portion of a rotational paraboloid being cut out, and a primary radiator which radiates a beam having an elliptical cone shape to an aperture plane of the reflector. A reflector contour of the aperture plane of the reflector is formed in an elliptical shape along an isolux line of an elliptical beam radiated from the primary radiator. Accordingly, a loss due to spillover of the reflector is compensated for in a space in which the reflector contour of the present embodiment protrudes from a general reflector contour having a virtual elliptical shape formed to be perpendicular to an axis of a beam incident on an aperture plane of the reflector. In a space in which the general reflector contour protrudes from the reflector contour of the present embodiment, degradation of illuminance efficiency of the reflector is compensated.

Antenna device including reflector and primary radiator

A direction deciding unit calculates a plane the perpendicular of which is a directional vector from the wireless communication apparatus toward a radio station. A group deciding unit decides, as groups, antenna combinations each consisting of some ones but not all of a plurality of antennas. A distance calculating unit calculates the distances each between the coordinates of antennas projected, in parallel with the directional vector, onto the plane, and further calculates, for each group, as a group shortest-distance of the group, the shortest one of the calculation results of the distances each between the coordinates of the antennas constituting the group. An identifying unit identifies a group the group shortest-distance of which is the longest. A plurality of communication units communicate with the radio station by use of respective ones of a plurality of antennas in the group identified by the identifying unit.

Radio communication device, radio communication method, and program

An array antenna includes: a plurality of first antenna elements arrayed at specified element intervals on a plane of a board; a plurality of second antenna elements arrayed at the element intervals in parallel to an array direction of the first antenna elements on the plane; a first power supply circuit for supplying electric power to the respective first antenna elements by a line branched at a first branch point on the plane; and a second power supply circuit for supplying electric power to the respective second antenna elements by a line branched at a second branch point shifted by a specified distance in the array direction with respect to the first branch point on the plane.

Array antenna and method for manufacutring array antenna

A first printed circuit board for vertical polarized wave has a plurality of vertical polarized wave elements which serves as antenna elements, and a first feeder circuit which is connected to the plurality of vertical polarized wave elements. A second printed circuit board for horizontal polarized wave has a second feeder circuit which is connected to a plurality of horizontal polarized wave elements which serves as antenna elements, and is mounted with the plurality of horizontal polarized wave elements. A cutout portion is provided between the adjacent two vertical polarized wave elements of the first printed circuit board, and the first and second printed circuit boards are arranged parallel so that the horizontal polarized wave elements are arranged in the cutout portions of the first printed circuit board. A reflecting plate has a concave section extending to one direction, and the plurality of vertical polarized wave elements and the plurality of horizontal polarized wave elements are arranged alternately in one direction inside the concave section.

Sector antenna

An antenna device of the invention comprises divider/combiner meansthat divides or combines a received signal into signals having a first phase distribution represented by an odd function, phase adding/removing means-that adds phases having a second phase distribution represented by an even function to the signals, or removes the phases from the signals, and a plurality of antenna elementsarranged in an array configuration, that transmits or receives the signals to which the phases have been added.

Antenna device, feed circuit, and radio-wave transmission/reception method

A helical antenna includes an element, a feeder circuit, and a connector that connects the element and feeder circuit. The element includes a cylindrical member composed of a dielectric and a plurality of radiation elements that are provided in helical form at intervals on the. outer surface of this cylindrical member. The feeder circuit is mounted on a circuit board that is arranged below the cylindrical member. The connector is arranged between the circuit board and the cylindrical member and is composed of an insulating material that is provided in a solid unit with connection pins that electrically connect the ends of the radiation elements to the circuit board.

Helical antenna with connector and fabrication method of the same

A helical antenna comprising a cylindrical dielectric member 1, four spiral conductors 2a to 2d which are wound around the outer wall of the cylindrical dielectric member 1, four spiral conductors 3a to 3d which are attached to the inner wall of the cylindrical dielectric member 1, and power supply circuits 4, 5 for supplying high-frequency power to the spiral conductors 2a to 2d and the spiral conductors 3a to 3d respectively. That is, the spiral conductors serving as radiation elements are disposed at the outside and inside of the cylindrical dielectric member, and the outer and inner conductors are operated as independent helical antennas. These spiral conductors are connected to the power supply circuits for supplying the high-frequency power having desired amplitude and phase.

Helical antenna

A helical antenna capable of covering a plurality of frequency bands and using a common feeder system for antenna elements adjusted to the respective frequency bands. First and second antenna elements having lengths corresponding to wavelengths of the frequency bands to be used are arranged helically at a specified pitch angle and spaced apart in the circumferential direction of a cylindrical body on the surface of a dielectric sheet wound around the outer circumferential surface of the cylindrical body. Coupling lines to be electromagnetically coupled to one-side ends of the antenna elements being adjacent to one another are formed on the surface of the dielectric sheet. A signal is fed from a common feeder circuit through the coupling lines to the respective antenna elements.

Method of producing a helical antenna and the helical antenna apparatus

A lens antenna having high antenna efficiency, low sidelobe levels, and that is easily assembled. The lens antenna includes a first horn made of a metallic conductor, a second horn made of a high-frequency absorbing plastic material, and a lens for controlling the power distribution at an aperature of the horn. Screws may be used to assemble the first horn, the second horn, and the lens. Though some of the microwave signals input through the circular waveguide of the first horn are reflected on the surface of the lens, most of the microwave signals are absorbed by the second horn. Moreover, because no wave absorber is bonded to an inner wall of a conical horn, nothing screens the microwave signal, the power density distribution at the aperture of the lens is not disrupted. Therefore, it is possible to obtain a desired power density distribution.

Growing community of inventors

Tokyo, Japan

Kosuke Tanabe