Radar antenna for use in a miniature unmanned aerial vehicle

A radar system, comprising:

• a radar antenna, for a miniature unmanned aerial vehicle, comprising:
• a first printed circuit board having a first array of antenna elements situated at positions thereon, wherein the positions of antenna elements of the first array of antenna elements lie within a first predetermined distance range from a central axis perpendicular to the first printed circuit board, and wherein individual antenna elements of the first array of antenna elements each lie in differing directions from the central axis;
• a second printed circuit board, which is parallel to the first printed circuit board, wherein the second printed circuit board having a second array of antenna elements situated at positions therein, wherein the positions of antenna elements of the second array of antenna elements lie within a second predetermined distance range from the central axis, and wherein individual antenna elements of the second array of antenna elements each lie in differing directions from the central axis, and wherein first element distances in the first predetermined distance range are smaller than second element distances in the second predetermined range;
• wherein one array of the first array of antenna elements and the second array of antenna elements is an array of transmission antenna elements, and the other array is an array of reception antenna elements;
• wherein the radar antenna further comprises:
• a first electrically conductive ring or plate that is:
• located between the first printed circuit board and the second printed circuit board, and
• blocks lines of sight from the antenna elements of the first array to the antenna elements of the second array;
• and
• a second electrically conductive ring or plate;
• wherein the second printed circuit board lies between the second electrically conductive ring or plate and the first electrically conductive ring or plate, and
• wherein the second electrically conductive ring or plate extends radially outward beyond the first electrically conductive ring or plate;
• and
• a third electrically conductive ring or plate,
• wherein the first printed circuit board lies between the third electrically conductive ring or plate and the first electrically conductive ring or plate, and
• wherein the first electrically conductive ring or plate extends radially outward beyond the third electrically conductive ring or plate;
• transmission electronics;
• and
• reception electronics,
• wherein the reception and transmission electronics being coupled to the arrays of first and second antenna elements respectively, or to the arrays of second and first antenna elements respectively.

A miniature unmanned aerial vehicle (UAV) comprising:

• a plurality of propellers configured to provide upward thrust,
• a UAV body connected to the plurality of propellers;
• and
• a radar antenna, hanging from the UAV body and comprising:
• a first printed circuit board having a first array of antenna elements situated at positions thereon, wherein the positions of antenna elements of the first array of antenna elements lie within a first predetermined distance range from a central axis perpendicular to the first printed circuit board, and wherein individual antenna elements of the first array of antenna elements each lie in differing directions from the central axis;
• a second printed circuit board, which is parallel to the first printed circuit board, wherein the second printed circuit board having a second array of antenna elements situated at positions therein, wherein the positions of antenna elements of the second array of antenna elements lie within a second predetermined distance range from the central axis, and wherein individual antenna elements of the second array of antenna elements each lie in differing directions from the central axis, and wherein first element distances in the first predetermined distance range are smaller than second element distances in the second predetermined range;
• wherein one array of the first array of antenna elements and the second array of antenna elements is an array of transmission antenna elements, and the other array is an array of reception antenna elements;
• wherein the radar antenna further comprises:
• a first electrically conductive ring or plate that is:
• located between the first printed circuit board and the second printed circuit board, and
• blocks lines of sight from the antenna elements of the first array to the antenna elements of the second array;
• and
• a second electrically conductive ring or plate;
• wherein the second printed circuit board lies between the second electrically conductive ring or plate and the first electrically conductive ring or plate, and
• wherein the second electrically conductive ring or plate extends radially outward beyond the first electrically conductive ring or plate;
• and
• a third electrically conductive ring or plate,
• wherein the first printed circuit board lies between the third electrically conductive ring or plate and the first electrically conductive ring or plate, and
• wherein the first electrically conductive ring or plate extends radially outward beyond the third electrically conductive ring or plate:
• wherein the first printed circuit board is positioned below the second printed circuit board of the radar antenna hanging from the UAV body.