US 12,170,411 B2
Antenna device, antenna module, communication device, and radar device
Hiroshi Nishida, Kyoto (JP)
Assigned to MURATA MANUFACTURING CO, LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Kyoto (JP)
Filed on Apr. 23, 2021, as Appl. No. 17/238,306.
Application 17/238,306 is a continuation of application No. PCT/JP2019/041981, filed on Oct. 25, 2019.
Claims priority of application No. 2018-202806 (JP), filed on Oct. 29, 2018.
Prior Publication US 2021/0242602 A1, Aug. 5, 2021
Int. Cl. H01Q 9/04 (2006.01); H01Q 19/02 (2006.01)
CPC H01Q 9/0407 (2013.01) [H01Q 19/023 (2013.01)] 17 Claims
OG exemplary drawing
 
1. An antenna device comprising:
a substrate that includes a plurality of insulating layers laminated one on top of another;
a ground electrode provided in or on the substrate;
a radiation electrode provided on the substrate; and
a waveguide structure that has:
a slit that is positioned in an electric field direction of the radiation electrode in plan view and that is provided in the ground electrode, and
a conductor wall that surrounds the slit and that extends in a thickness direction of the substrate, wherein:
a dimension of the waveguide structure in a magnetic field direction of the radiation electrode in the plan view is greater than ½ of a wavelength of a radio wave emitted by the radiation electrode in a medium of the substrate,
the radiation electrode and the slit are provided in different positions in the plan view,
a length from the slit to a terminal portion of the waveguide structure in the electric field direction of the radiation electrode in the plan view is about ¼ of a wavelength of the radio wave emitted by the radiation electrode in the waveguide structure,
the radiation electrode is disposed on a first surface of the substrate, and
the waveguide structure is provided so as to be exposed in the first surface of the substrate.