ANTENNA FOR A PLURALITY OF BANDS

摘要

There is provided an antenna for a plurality of bands using a single antenna element (10) which can be used in a plurality of frequency bands and can be reduced in size. The antenna element (10) has one end A which is electrically connected to a power feed point (12) and intermediate points B and C, and the other end D which are electrically connected to a grounding conductor (14) via switches SWb, SWc, and SWd, respectively. The electric length from the one end A of the antenna element (10) to the points where the intermediate points B and C are grounded via the switches SWb and SWc to the grounding conductor (14) and the electric length from the end A to the point where the other end D is connected via the switch SWd to the grounding conductor (14) are respectively set so that different desired frequency bands can resonate. By closing one of the switches SWb, SWc, and SWd, it is possible to select one of the desired frequency bands for resonance. Thus, the single antenna element (10) can function as an antenna in a plurality of frequency bands.