| 摘要 |
PROBLEM TO BE SOLVED: To provide an antenna unit that has satisfactorily controllable directivity even in a rough design.SOLUTION: The antenna unit includes a planar antenna, and a metal casing substantially in the shape of a rectangular parallelepiped housing the planar antenna with a surface thereof directed at the front. The casing has an open front, and one open face out of upper, lower, left and right sides. A distance a from the planar antenna to each of two sides having the open side of the casing in between and a back is λ/6≤a≤λ/2.2, where λ is a wavelength of a target frequency. A distance b from the planar antenna to the side opposite to the open side of the casing may be λ/20≤b≤λ/4. |
