Patent ID: 8766854

Claim:
A bottom feed cavity aperture antenna, comprising: a patch, feeding a signal to the bottom feed cavity aperture antenna; a ground structure, comprising a continuous wall, and a top end and a bottom end, wherein the continuous wall surrounds the patch and defines a radiation area, a structural thickness of the ground structure is formed between the top end and the bottom end, a patch height is formed between the patch and the bottom end, and a ratio of the patch height to the structural thickness is substantially lower than 1/2, and a magnetic field is formed at the top end, and magnetic resonance directions of the magnetic field are parallel to a first axis, wherein the ground structure defines an aperture; and a top sheet arranged to define impedance matching and gain patterns of the bottom feed cavity aperture antenna, wherein the top sheet merely partially covers the aperture, wherein the top sheet is rectangular, wherein the top sheet has a major axis and a minor axis, the major axis is longer than the minor axis, and the major axis is parallel to the first axis, and wherein two ends of the top sheet respectively contact a top edge of the ground structure; wherein an electric field is formed at the top end, electric resonance directions of the electric field are parallel to a second axis, and the first axis is perpendicular to the second axis, and wherein the top sheet is metal, and the top sheet is electrically connected to the ground structure.