Furuno Electric Company Limited

Kohji Yano

Mitsuhiko Hataya

An antenna device vertically rotatable and horizontally rotatable is provided, which has a configuration in which waveguides are effectively disposed. An antenna device includes an antenna, a vertically rotating, and a rotary joint. The antenna is vertically rotatable and horizontally rotatable, and outwardly radiates a radio wave. The vertically rotating is disposed such that a longitudinal direction thereof is along an axial line of the vertical rotation and intersects perpendicularly with an axial line of the horizontal rotation. The rotary joint is coupled to the vertically rotating. Moreover, the antenna device includes a waveguide path passing through the inside of the rotary and the inside of the vertically rotating and connected with the antenna.

Antenna device

A slot array antenna where slots are arrayed in two directions is provided for suppressing occurrence of side lobes. An antenna includes a radiation waveguide part and stubs. The radiation waveguide part has two sheets of metal plates facing each other and outwardly radiates a radio wave from a plurality of slots formed in one of the metal plates. Each stub is arranged for every slot to extend inward of the radiation waveguide part from the face where the slots are formed, and changes a transmission mode of the radio wave within the radiation waveguide part. The slots are narrow and arranged at fixed intervals in both a longitudinal direction and a lateral direction of the slots. The stub is disposed for every slot, on either side of the slot in the lateral direction. Between the adjacent slots, the stubs are disposed on the opposite sides in the lateral direction.

Antenna and method of manufacturing the antenna

A compact antenna that includes a power feeding waveguide, a sub reflection mirror, and a main reflection mirror. Radio waves comprised of a vertical polarized wave and a horizontal polarized wave are transmitted to the power feeding waveguide. The sub reflection mirror is disposed to face an opening of the power feeding waveguide and reflects the radio wave radiated from the opening. The main reflection mirror is disposed to face the sub reflection mirror and outwardly radiates the radio wave reflected by the sub reflection mirror. A front surface of the main reflection mirror has a shape formed by rotating a line reaching one side and the other side of a predetermined parabola curve at least once, around a rotational axis. A front surface of the sub reflection mirror has a shape formed by rotating either one of a stepped line and a wavy line around the rotational axis.

Growing community of inventors

Nishinomiya, Japan

Kohji Yano