| 摘要 |
<P>PROBLEM TO BE SOLVED: To compose a two-frequency sharing dipole antenna. <P>SOLUTION: A first dipole antenna 2 including a first resonant frequency is composed of elements 7a, 7b and a transmission line 9, and a second dipole antenna 3 including a second resonant frequency (> the first resonant frequency) is composed of elements 8a, 8b and the transmission line 9. The transmission line 9 is composed of a coplanar strip 10 and a coplanar line 11 and connects the antenna to a coaxial cable 4. The transmission line 9 functions as a matching circuit which attains impedance matching between the antenna and the coaxial cable when operating in the first resonant frequency, and makes the coplanar line 11 function as a balun between the antenna and the coaxial cable 4 by making the impedance of the coplanar line 11 equal with that of the coaxial cable 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
