| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an antenna system configured to enable even turning to into multi-frequencies, and the impedance of which will not be decreased, when being built in a housing located close to a board of a portable wireless communications apparatus. <P>SOLUTION: A half wavelength dipole antenna is folded to configure a folded monopole antenna 2L, comprising a forward path part 21L, a folded part 22L, and a return path part 23L, energized from a feeding part 11 at a feeding point 20 and grounded to the board 11 at a ground point 24L. Further, a basic form of the antenna system 2 is configured, by symmetrically placing an additional antenna 2R to the folded monopole antenna 2L. Moreover, modifications of the antenna system 2 are configured, in such a way that the folded monopole antenna 2L and the additional antenna 2R are disposed asymmetrically, a branch element or an inter-line short-circuit part (not shown) is attached to the folded monopole antenna 2L, and a monopole antenna or a dipole antenna or the like is added to the folded monopole antenna 2L to attain feeding from the shared feeding part 11. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
