| 摘要 |
PROBLEM TO BE SOLVED: To provide an antenna that prevents generation of a region incapable of communication in a target communication region.SOLUTION: The antenna includes: a leakage coaxial cable 3 having a central conductor extending axially from one end of supply of a signal to the other end, an insulator covering the central conductor and an outer conductor covering the central conductor via the insulator, and having a plurality of first slots and a plurality of second slots with a constant axial pitch in the outer conductor; and a terminator 5 connected to the other end, terminating with a characteristic impedance of the leakage coaxial cable and having a sheath conductor connected to the outer conductor. The pitch is regulated by a free space wavelength of the signal and a dielectric constant of the insulator such that, in a plane parallel to the axial direction, only a first polarized wave whose electric field is a component circumferential of the leakage coaxial cable 3 is radiated from the plurality of first and second slots at a radiation angle inclined to the one end side of a normal to the leakage coaxial cable 3, and a second polarized wave whose electric field is an axial component is radiated in the normal direction from the sheath conductor. |
