| 摘要 |
<p>PROBLEM TO BE SOLVED: To keep communication sensitivity in global peripheral directions by combining a circularly polarized wave antenna provided with high elevation angle direcitivity and a linearly polarized wave antenna provided with directivity in a low elevation angle. SOLUTION: A linearly polarized wave antenna means 11 is a vertical dipole antenna and is composed of a first radiation element 12, a power feeding point 13, a second radiation element 14 composed of the sleeve of a conductor and a coaxial line (power feeding line) 15. A circularly polarized wave antenna means 21 is a helical antenna and is composed of the power feeding point 22, the coaxial line 23 to be a radiation element, the conductor 24 and a dielectric cylinder 25. In this case, the radiation direction of the circularly polarized wave antenna means 21 is in a high elevation angle direction and the radiation direction of the linearly polarized wave antenna means 11 is in a low elevation angle direction. The operation frequencies of the two antennas 21 and 11 are matched to the desired same frequency band. Then, the circularly polarized wave antenna 21 and the linearly polarized wave antenna 11 are arranged at the upper end part of this portable radio equipment 1. Thus, even at the time of being at the low elevation angle or a high elevation angle, excellent communication is made possible.</p> |
