| 主权项 |
1. A mixer circuit comprising:
a first single-ended to differential converter having an input terminal adapted for receiving an input voltage signal, a first output terminal and a second output terminal, said first single-ended to differential converter converting the input voltage signal into a differential input voltage signal pair that includes a first voltage signal and a second voltage signal, and outputting the first and second voltage signals respectively at said first and second output terminals; a first transistor having a first terminal for providing a first current signal, a second terminal, and a control terminal coupled to said first output terminal of said first single-ended to differential converter for receiving the first voltage signal therefrom; a second transistor having a first terminal for providing a second current signal, a second terminal, and a control terminal coupled to said second output terminal of said first single-ended to differential converter for receiving the second voltage signal therefrom, the first and second current signals cooperatively constituting a differential input current signal pair; a first inductive transmission line having a first terminal coupled to said second terminal of said first transistor, and a second terminal; a second inductive transmission line having a first terminal coupled to said second terminal of said first inductive transmission line, and a second terminal coupled to said second terminal of said second transistor; a third inductive transmission line having a first terminal, and a second terminal coupled to said first terminal of said first transistor; a fourth inductive transmission line having a first terminal, and a second terminal coupled to said first terminal of said second transistor; a mixer receiving a differential oscillatory voltage signal pair, and coupled to said first terminals of said third and fourth inductive transmission lines for receiving the differential input current signal pair through said third and fourth inductive transmission lines, said mixer mixing the differential input current signal pair with the differential oscillatory voltage signal pair to obtain a differential mixed voltage signal pair; and a fifth inductive transmission line having a first terminal adapted to be coupled to a signal source for receiving the input voltage signal therefrom, and a second terminal coupled to said input terminal of said first single-ended to differential converter; wherein said first and second inductive transmission lines are configured such that an equivalent input impedance seen into said first and second transistors from said control terminals thereof matches an equivalent output impedance seen into said first single-ended to differential converter from said first and second output terminals thereof; wherein an equivalent input impedance seen into said fifth inductive transmission line from said first terminal thereof matches an equivalent output impedance seen into the signal source. |
