Abstract: A diplexer that can demultiplex and multiplex two signals having wide frequency bands, and a wireless communication module and a wireless communication apparatus using the same, are provided. A diplexer has a multilayer body including a first interlayer, a second interlayer and a third interlayer. On the first interlayer, first resonant electrodes are disposed in an interdigital form. On the second interlayer, a plurality of second resonant electrodes are disposed in an interdigital form. On the third interlayer, there are disposed an input coupling electrode that faces the input-stage first resonant electrode and the input-stage second resonant electrode in an interdigital form, a first output coupling electrode that faces the output-stage first resonant electrode in an interdigital form, and a second output coupling electrode that faces the output-stage second resonant electrode.

Abstract: An ultra-wideband bandpass filter having two adequately-wide pass bands, and a wireless communication module and a wireless communication apparatus which employ the bandpass filter are provided. In a bandpass filter, first resonant electrodes are arranged on a first interlayer of a multilayer body in an interdigital form; a plurality of second resonant electrodes are arranged on a second interlayer in an interdigital form; and an input coupling electrode and an output coupling electrode are arranged on a third interlayer located between the first interlayer and the second interlayer. The input coupling electrode faces an input-stage first resonant electrode and an input-stage second resonant electrode in an interdigital form. The output-coupling electrode faces an output-stage first resonant electrode and an output-stage second resonant electrode in an interdigital form.

Abstract: A bandpass filter for a wide frequency band such as UWB is disclosed. The bandpass filter comprises a laminate of a plurality of dielectric layers, a first ground electrode connected to a ground potential, a plurality of resonant electrodes in a first inter-layer and a plurality of coupling electrodes in a second inter-layer. A transmission characteristic of the bandpass filter having flat and low loss over the entire region of the broad pass band can be achieved.

Abstract: The present invention provides a high-frequency switching circuit comprising: two or more high-frequency switches SW1 and SW2 provided correspondingly to a plurality of communication systems having mutually different frequency bands; and a control circuit DEC1 adapted to control the switching of the two or more high-frequency switches SW1 and SW2, in which a common antenna terminal ANT3 and common terminals ANT1 and ANT2 of the respective high-frequency switches SW1 and SW2 are connected via a matching circuit MAT1 having a filtering function capable of allowing passage of direct current. When one path of the high-frequency switch SW1 is turned on, the other paths of the high-frequency switch SW1 and all paths of the high-frequency switch SW2 can be turned off.

Abstract: A high-frequency module comprises: a diplexer connected to an antenna terminal for branching a plurality of transmission/reception systems different in pass band from one another; switch circuits for switching the transmission/reception systems to transmission systems and reception systems; power amplifiers for amplifying transmission signals in the pass bands of the transmission systems; and matching circuits for matching the impedances of the power amplifiers to one another. The power amplifiers and the switch circuits are respectively formed by high-frequency semiconductor integrated circuit elements, and these high-frequency semiconductor integrated circuit elements are mounted on the surface of the multi-layer substrate. The high-frequency module is reduced both in size and loss and increased in isolation in its entirety.

Abstract: The present invention provides a high-frequency switching circuit comprising: two or more high-frequency switches SW1 and SW2 provided correspondingly to a plurality of communication systems having mutually different frequency bands; and a control circuit DEC1 adapted to control the switching of the two or more high-frequency switches SW1 and SW2, in which a common antenna terminal ANT3 and common terminals ANT1 and ANT2 of the respective high-frequency switches SW1 and SW2 are connected via a matching circuit MAT1 having a filtering function capable of allowing passage of direct current. When one path of the high-frequency switch SW1 is turned on, the other paths of the high-frequency switch SW1 and all paths of the high-frequency switch SW2 can be turned off.

Abstract: A high-frequency module comprises: a diplexer connected to an antenna terminal for branching a plurality of transmission/reception systems different in pass band from one another; switch circuits for switching the transmission/reception systems to transmission systems and reception systems; power amplifiers for amplifying transmission signals in the pass bands of the transmission systems; and matching circuits for matching the impedances of the power amplifiers to one another. The power amplifiers and the switch circuits are respectively formed by high-frequency semiconductor integrated circuit elements, and these high-frequency semiconductor integrated circuit elements are mounted on the surface of the multi-layer substrate. The high-frequency module is reduced both in size and loss and increased in isolation in its entirety.