Abstract: A resonant circuit to be connected to a negative resistance unit is disclosed. The resonant circuit includes a pair of resonant transmission lines electrically coupled to each other and a coupling transmission line connecting the resonant transmission lines. The resonant transmission lines and the coupling transmission line are formed on a semiconductor substrate. The resonant transmission lines have a length corresponding to a quarter wavelength (?/4) of twice of the resonant frequency attributed to the resonant circuit.

Abstract: A marchand balun with a reduced plane size is disclosed. The marchand balun provides two coupling units each having two transmission lines coupled to each other and having a length of ?/8, where ? is a characteristic wavelength of a signal subject to the marchand balun. The marchand balun further provides an additional unit, where two coupling unit and the additional unit are connected in series to each other. The additional unit is one of a transmission line with a length of ?/16 with one open end and a capacitor with one grounded end.

Abstract: A two-stage amplifier of a type of the current re-use configuration is disclosed. The amplifier includes first to third transistors, where the first transistor constitute the first stage, while, the latter two transistors constitute the second stance. The first to third transistors are connected in series between a power supply and ground such that a bias current supplied to the third transistor flows in the second and first transistors. The first transistor in the source thereof is grounded in the DC mode. The second transistor is grounded in the AC mode but floated in the DC mode. The third transistor that outputs an amplified signal is connected in parallel in the AC mode but in series in the DC mode with respect to the second transistor.

Abstract: A two-stage amplifier of a type of the current re-use configuration is disclosed. The amplifier includes first to third transistors, where the first transistor constitute the first stage, while, the latter two transistors constitute the second stance. The first to third transistors are connected in series between a power supply and ground such that a bias current supplied to the third transistor flows in the second and first transistors. The first transistor in the source thereof is grounded in the DC mode. The second transistor is grounded in the AC mode but floated in the DC mode. The third transistor that outputs an amplified signal is connected in parallel in the AC mode but in series in the DC mode with respect to the second transistor.

Abstract: A marchand balun with a reduced plane size is disclosed. The marchand balun provides two coupling units each having two transmission lines coupled to each other and having a length of ?/8, where ? is a characteristic wavelength of a signal subject to the marchand balun. The marchand balun further provides an additional unit, where two coupling unit and the additional unit are connected in series to each other. The additional unit is one of a transmission line with a length of ?/16 with one open end and a capacitor with one grounded end.

Abstract: An electronic device comprises a divider and a first filter. The divider comprises a first terminal for inputting a high-frequency signal, a second terminal coupled to the first terminal, and third and fourth terminals for distributing thereto the signal inputted from the first terminal. The first filter is coupled to the second terminal.

Abstract: A resonant circuit to be connected to a negative resistance unit is disclosed. The resonant circuit includes a pair of resonant transmission lines electrically coupled to each other and a coupling transmission line connecting the resonant transmission lines. The resonant transmission lines and the coupling transmission line are formed on a semiconductor substrate. The resonant transmission lines have a length corresponding to a quarter wavelength (?/4) of twice of the resonant frequency attributed to the resonant circuit.

Abstract: An electronic device comprises a divider and a first filter. The divider comprises a first terminal for inputting a high-frequency signal, a second terminal coupled to the first terminal, and third and fourth terminals for distributing thereto the signal inputted from the first terminal. The first filter is coupled to the second terminal.

Abstract: A mixer includes a first node to which an intermediate frequency (IF) signal is input; first and second transistors that respectively have control terminals supplied with local signals having mutually opposite phases and output terminals connected to the first node; a first filter that is connected between the output terminal of the second transistor and the first node and suppresses passage of the IF signal; a second node to which the IF signal is input; third and fourth transistors that respectively have control terminals supplied with local signals having mutually opposite phases and output terminals connected to the second node; a second filter that is connected between the output terminal of the fourth transistor and the second node and suppresses passage of the IF signal; and a combiner combining a signal output from the first node and a signal output from the second node.

Abstract: A mixer includes a first node to which an intermediate frequency (IF) signal is input; first and second transistors that respectively have control terminals supplied with local signals having mutually opposite phases and output terminals connected to the first node; a first filter that is connected between the output terminal of the second transistor and the first node and suppresses passage of the IF signal; a second node to which the IF signal is input; third and fourth transistors that respectively have control terminals supplied with local signals having mutually opposite phases and output terminals connected to the second node; a second filter that is connected between the output terminal of the fourth transistor and the second node and suppresses passage of the IF signal; and a combiner combining a signal output from the first node and a signal output from the second node.

Abstract: A mixer includes a first node to which an intermediate frequency (IF) signal is input; first and second transistors that respectively have control terminals supplied with local signals having mutually opposite phases and output terminals connected to the first node; a first filter that is connected between the output terminal of the second transistor and the first node and suppresses passage of the IF signal; a second node to which the IF signal is input; third and fourth transistors that respectively have control terminals supplied with local signals having mutually opposite phases and output terminals connected to the second node; a second filter that is connected between the output terminal of the fourth transistor and the second node and suppresses passage of the IF signal; and a combiner combining a signal output from the first node and a signal output from the second node.

Abstract: A high frequency amplifier circuit includes a first transistor that has a first terminal, a second terminal and a control terminal, the first terminal being grounded, a second transistor that has a first terminal, a second terminal and a control terminal, the control terminal of the second transistor being coupled to the second terminal of the first transistor, the first terminal of the second transistor being coupled to only the second terminal of the first transistor with respect to high frequency wave, the second terminal of the second transistor being coupled to a direct-current power supply, and a first resistor of which first terminal is coupled to a node between the second terminal of the first transistor and the control terminal of the second transistor, and of which second terminal is coupled to the first terminal of the second transistor.

Abstract: A mixer includes a first node to which an intermediate frequency (IF) signal is input; first and second transistors that respectively have control terminals supplied with local signals having mutually opposite phases and output terminals connected to the first node; a first filter that is connected between the output terminal of the second transistor and the first node and suppresses passage of the IF signal; a second node to which the IF signal is input; third and fourth transistors that respectively have control terminals supplied with local signals having mutually opposite phases and output terminals connected to the second node; a second filter that is connected between the output terminal of the fourth transistor and the second node and suppresses passage of the IF signal; and a combiner combining a signal output from the first node and a signal output from the second node.

Abstract: A circuit includes: a first line to which input and output signal terminals are connected; a first transistor having a first terminal connected to the first line, a second terminal connected to a ground potential, and a control terminal supplied with a first oscillation signal, the first transistor outputting the first signal and its harmonic component; a second transistor having a first terminal connected to the first line, a second terminal connected to the ground potential, and a control terminal supplied with a second oscillation signal, the second transistor outputting the second signal and its harmonic component; a first harmonic generator connected to the control terminal of the first transistor and generates a harmonic component including the harmonic component by the first transistor; and a second harmonic generator connected to the control terminal of the second transistor and generates a harmonic component including the harmonic component by the second transistor.

Abstract: An electronic circuit includes: first through third transistors having a control terminal, first and second terminals; a first direct current path supplying a direct current having passed through between the first terminal and the second terminal of at least one of the second transistor and the third transistor to the second terminal of the transistor at former position compared to the transistor through which the direct current passed; a second direct current path that is different from the first direct current path and supplies a direct current having passed through between the first terminal and the second terminal of at least one of the second transistor and the third transistor to the second terminal of the transistor at former position compared to the transistor through which the direct current passed; and a common coupling point coupling the first direct current path and the second direct current path in common.

Abstract: A high frequency amplifier circuit includes a first transistor that has a first terminal, a second terminal and a control terminal, the first terminal being grounded, a second transistor that has a first terminal, a second terminal and a control terminal, the control terminal of the second transistor being coupled to the second terminal of the first transistor, the first terminal of the second transistor being coupled to only the second terminal of the first transistor with respect to high frequency wave, the second terminal of the second transistor being coupled to a direct-current power supply, and a first resistor of which first terminal is coupled to a node between the second terminal of the first transistor and the control terminal of the second transistor, and of which second terminal is coupled to the first terminal of the second transistor.

Abstract: An electronic circuit includes a first transistor having a first terminal grounded, a second transistor having a control terminal coupled with a second terminal of the first transistor, a first terminal grounded via a first capacitor, and a second terminal to which a DC power supply is connected, a first distributed constant line having one end connected to a first node between the second terminal of the first transistor and the control terminal of the second transistor and another end grounded via a second capacitor, a second distributed constant line having one end connected to the second terminal of the first transistor and another end connected to the first node, a third distributed constant line having one end connected to the control terminal of the second transistor and another end connected to the first node, a resistor connected between a second node between the first line and the second capacitor and a third node between the first terminal of the second transistor and the first capacitor, and a path

Abstract: An electronic circuit includes: first through third transistors having a control terminal, first and second terminals; a first direct current path supplying a direct current having passed through between the first terminal and the second terminal of at least one of the second transistor and the third transistor to the second terminal of the transistor at former position compared to the transistor through which the direct current passed; a second direct current path that is different from the first direct current path and supplies a direct current having passed through between the first terminal and the second terminal of at least one of the second transistor and the third transistor to the second terminal of the transistor at former position compared to the transistor through which the direct current passed; and a common coupling point coupling the first direct current path and the second direct current path in common.

Abstract: A circuit includes: a first line to which input and output signal terminals are connected; a first transistor having a first terminal connected to the first line, a second terminal connected to a ground potential, and a control terminal supplied with a first oscillation signal, the first transistor outputting the first signal and its harmonic component; a second transistor having a first terminal connected to the first line, a second terminal connected to the ground potential, and a control terminal supplied with a second oscillation signal, the second transistor outputting the second signal and its harmonic component; a first harmonic generator connected to the control terminal of the first transistor and generates a harmonic component including the harmonic component by the first transistor; and a second harmonic generator connected to the control terminal of the second transistor and generates a harmonic component including the harmonic component by the second transistor.

Abstract: An electronic circuit includes a first transistor having a first terminal grounded, a second transistor having a control terminal coupled with a second terminal of the first transistor, a first terminal grounded via a first capacitor, and a second terminal to which a DC power supply is connected, a first distributed constant line having one end connected to a first node between the second terminal of the first transistor and the control terminal of the second transistor and another end grounded via a second capacitor, a second distributed constant line having one end connected to the second terminal of the first transistor and another end connected to the first node, a third distributed constant line having one end connected to the control terminal of the second transistor and another end connected to the first node, a resistor connected between a second node between the first line and the second capacitor and a third node between the first terminal of the second transistor and the first capacitor, and a path