Antenna system

An antenna system comprising:

• a ground plate;
• a primary radiator disposed on an upper surface of said ground plate;
• a main reflector having a predetermined focal point or a predetermined focal line and standing on the upper surface of said around plate such that said focal point or said focal line substantially corresponds to the location of said primary radiator;
• and
• a polarizer, composed of a plurality of grooves an-angled at predetermined intervals and extending in the direction at approximately 45° with respect to the normal line of said ground plate, said polarizer being disposed on a mirror surface of said main reflector facing said primary radiator.

An antenna system comprising:

• a ground plate;
• a primary radiator disposed on an upper surface of said ground plate;
• a main reflector having a predetermined focal point or a predetermined focal line and standing on the upper surface of said ground plate such that said focal point or said focal line substantially corresponds to the location of said primary radiator;
• and
• a linear conductor element composed of a plurality of linear conductors arranged at predetermined intervals and extending in the direction at approximately 45° with respect to the normal line of said ground plate, said linear conductor element being disposed on a mirror surface of said main reflector facing said primary radiator.

An antenna system comprising:

• a ground plate;
• a primary radiator disposed on an upper surface of said ground plate;
• a main reflector having a predetermined focal point or a predetermined focal line and standing on the upper surface of said ground plate such that said focal point or said focal line substantially corresponds to the location of said primary radiator;
• and
• a polarizer composed of meander-line conductors for convening a linearly polarized wave and a circularly polarized wave, said polarizer being disposed between said main reflector and said primary radiator, or between said main reflector and an object to which the antenna system radiates radio waves or which radiates radio waves to the antenna system.

An antenna system comprising:

• a ground plate;
• a primary radiator disposed on an upper surface of said ground plate;
• and
• a main reflector having a predetermined focal point or a predetermined focal line and standing on the upper surface of said ground plate such that said focal point or said focal line substantially corresponds to the location of said primary radiator;
• wherein said primary radiator includes:
• a feed probe disposed on said ground plate so as to protrude fro the upper surface thereof;
• a feed probe external conductor disposed on the ground plate so as to surround said feed probe, said feed probe external conductor being electrically connected to said ground plate;
• a feed slot formed in said feed probe external conductor in a portion facing said main reflector;
• and
• an antenna element disposed in the vicinity of said feed slot and electromagnetically coupled with said feed probe.

An antenna system comprising:

• a ground plate;
• a primary radiator disposed on an upper surface of said ground plate;
• and
• a main reflector having a predetermined focal point or a predetermined focal line and standing on the upper surface of said ground plate such that said focal point or said focal line substantially corresponds to the location of said primary radiator,
• wherein said main reflector includes a plurality of reflector regions having different inclination angles with respect to said ground plate.