Slot array antenna

A slot array antenna for use in at least one of transmission and reception of an electromagnetic wave of a band having a central wavelength λo in free space, comprising:

• an electrically conductive member having an electrically conductive surface and a slot row including a plurality of slots, the plurality of slots being arrayed in a first direction which extends along the electrically conductive surface;
• a waveguide member having an electrically conductive waveguide face which opposes the plurality of slots and extends along the first direction;
• and
• an artificial magnetic conductor extending on both sides of the waveguide member, wherein,
• a width of the waveguide face is less than λo/2;
• at least one of the electrically conductive member and the waveguide member includes a plurality of additional elements on at least one of the electrically conductive surface and the waveguide face;
• the plurality of additional elements include at least one first type of additional element and/or at least one second type of additional element;
• the at least one first type of additional element is a bump being provided on either the electrically conductive surface or the waveguide face and serving to narrow a spacing between the electrically conductive surface and the waveguide face relative to any adjacent site, or a broad portion serving to broaden the width of the waveguide face relative to any adjacent site;
• and
• the at least one second type of additional element is a dent being provided on either the electrically conductive surface or the waveguide face and serving to broaden the spacing between the electrically conductive surface and the waveguide face relative to any adjacent site, or a narrow portion serving to narrow the width of the waveguide face relative to any adjacent site, wherein,
• (a) the at least one first type of additional element is adjacent along the first direction to the at least one second type of additional element or at least one neutral portion lacking the at least one additional element, and a central position of the at least one first type of additional element is more distant than 1.15λo/8 along the first direction from a central position of the at least one second type of additional element or the at least one neutral portion;
• or
• (b) the at least one second type of additional element is adjacent along the first direction to the at least one first type of additional element or at least one neutral portion lacking the at least one additional element, and a central position of the at least one first type of additional element is more distant than 1.15λo/8 along the first direction from a central position of the at least one second type of additional element or the at least one neutral portion.

A slot array antenna for use in at least one of transmission and reception of an electromagnetic wave of a band having a central wavelength λo in free space, comprising:

• an electrically conductive member having an electrically conductive surface and a slot row including a plurality of slots, the plurality of slots being arrayed in a first direction which extends along the electrically conductive surface;
• a waveguide member having an electrically conductive waveguide face which opposes the plurality of slots and extends along the first direction;
• and
• an artificial magnetic conductor extending on both sides of the waveguide member, wherein,
• a width of the waveguide face is less than λo/2;
• at least one of the electrically conductive member and the waveguide member includes a plurality of additional elements on at least one of the electrically conductive surface and the waveguide face;
• the plurality of additional elements include at least one third type of additional element and/or at least one fourth type of additional element;
• the at least one third type of additional element is a bump being provided on either the electrically conductive surface or the waveguide face and serving to narrow a spacing between the electrically conductive surface and the waveguide face relative to any adjacent site, the width of the waveguide being narrowed at the bump relative to any adjacent site;
• and
• the at least one fourth type of additional element is a dent being provided on either the electrically conductive surface or the waveguide face and serving to broaden the spacing between the electrically conductive surface and the waveguide face relative to any adjacent site, the width of the waveguide being broadened at the bump relative to any adjacent site, wherein,
• (c) the at least one third type of additional element is adjacent along the first direction to the at least one fourth type of additional element or at least one neutral portion lacking the at least one additional element, and a central position of the at least one third type of additional element is more distant than 1.15λo/8 along the first direction from a central position of the at least one fourth type of additional element or the at least one neutral portion;
• or
• (d) the at least one fourth type of additional element is adjacent along the first direction to the at least one third type of additional element or at least one neutral portion lacking the at least one additional element, and a central position of the at least one fourth type of additional element is more distant than 1.15λo/8 along the first direction from a central position of the at least one third type of additional element or the at least one neutral portion.