| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a sleeve antenna structure which is used commonly for 2 frequencies and is low in manufacturing cost. <P>SOLUTION: The sleeve antenna common to 2 frequencies includes a radiation element 8a, formed by removing an exterior conductor from a coaxial power supply line 1 as a tip part thereof, a radiation element 9b for transmission and reception of a first frequency, an inductance element 9 provided between the radiation elements 8a and 8b, sleeve elements 10a and 10c for transmission and reception of first and second frequencies, sleeves 10b and 10d for transmission of the first frequency, and an inductance element 10d provided between the sleeves 10a, 10c and 10b, 10d. The sleeve antenna for the 2 frequencies is housed in a radome 20 of a sleeve antenna for one frequency. <P>COPYRIGHT: (C)2003,JPO |
