Abstract: A ceramic chip antenna, which has a small size and a broad bandwidth, is provided. The ceramic chip antenna consists of a ceramic body with cuboid shape, a conductor wound helically inside the ceramic body, and signal-feed terminal formed on a surface of the ceramic body. The ceramic chip antenna with a helical conductor patterns formed in a symmetrical dipole shape is provided, which has a high gain value and excellent radiation characteristics. Also, it can be built-in inside a mobile terminal due to its small size. The ceramic chip antenna according to the present invention can have a broad bandwidth that satisfies the variable frequency of the present mobile communication system.

Abstract: A monoblock dielectric duplexer comprises resonant holes. Conductive electrodes and couplers are formed on one side of the dielectric block, whose other sides are covered with a conductive material. The conductive electrodes in a transmit-filtering portion are formed in an inter-digitating manner while the conductive electrodes in receive-filtering portion are formed to be of pad-shape. In the duplexer, capacitances of capacitors comprised of the conductive electrodes are easily and accurately set to desired values by determining the number and/or the lengths of fingers that the inter-digitating electrodes have.