Radio frequency mixer
AssigneeZenith Electronics Corporation
InventorPierre Dobrovolny
Life of this patent
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Abstract
An RF mixer combines electrical and structural aspects to create a more efficient device. Diodes are coaxially mounted within two conductive tubes which form shields. The respective diode or diodes associated with each of the tubes are cross-connected at the LO port to the tube associated with the other diode or diodes. A capacitor compensates the inductance associated with the outer surfaces of the tubes. At their other ends, the tubes are coupled to ground and the diodes are coupled to an RF/IF bandsplitting network.
Claims14
A mixer having a balanced LO port and an RF/IF port comprising:
- first and second shield means;
- first and second diodes symmetrically and respectively shielded by said first and second shield means and disposed between said LO and RF/IF ports;
- means at said LO port for coupling said first diode with said second shield means and said second diode with said first shield means;
- and
- means at said RF/IF port for terminating said diodes and said shield means such that said diodes are operatively coupled in parallel across said LO port.
A mixer having a balanced LO port and an RF/IF port comprising:
- first and second shield means;
- first and second diodes symmetrically and respectively shielded by said first and second shield means and disposed between said LO and RF/IF ports;
- means at said LO ports for coupling the anode of said first diode to said second shield means and the cathode of said second diode to said first shield means;
- and
- means at said RF/IF port for coupling both of said shield means to ground potential and for coupling the cathode of said first diode to the anode of said second diode for producing, with respect to the LO signal, a virtual ground therebetween, whereby said diodes are operatively coupled in parallel across said LO port.
A mixer having a balanced LO port and an RF/IF port comprising:
- first and second spaced substantially parallel printed-circuit boards respectively associated with said LO and RF/IF ports, each of said boards including an insulating support with a metallic film on each side thereof;
- first and second hollow tubular shields electrically interconnecting inner and confronting metallic films of said printed circuit boards;
- first and second diodes respectively mounted coaxially with said first and second tubular shields;
- means associated with said first printed circuit board for coupling said first diode with said second tubular shield and said second diode with said first tubular shield;
- and
- means associated with said second printed circuit board for coupling said tubular shields to ground potential and for coupling said first diode to said second diode for producing, with respect to the LO signal, a virtual ground therebetween.
A radio frequency mixer comprising a support board, two diodes having electrodes, a first U-shaped strip line of conductive material on one side of said board, the arms of said first U-shaped strip line being interrupted to provide points for electrically connecting to electrodes of respective ones of said two diodes, a terminal formed at the outer end of each of said arms and in the center of the bight of said first U-shaped strip line, a second U-shaped metallic area on the other side of said board, said second U-shaped area being juxtaposed to said first U-shaped strip line and positioned to provide grounded shielding for the first U-shaped strip line, a terminal formed at each of the outer ends and at the bight of said second U-shaped area, a first cross-connection from said terminal at a left arm of said first U-shaped strip line to said terminal at a right arm of said second U-shaped area, a second cross-connection from said terminal at a right arm of said first U-shaped strip line to said terminal at a left arm of said second U-shaped area, and a capacitor coupled between said first and second cross-connections, and a ground connection to said bight terminal on said second U-shaped area.
A mixer having a balanced LO port and an RF/IF port comprising:
- first and second transmission line means;
- first and second diodes symmetrically coupled as a part of said first and second transmission line means respectively and disposed between said LO and RF/IF ports;
- means at said LO port for coupling said first diode with said second transmission line means and said second diode with said first transmission line means;
- and
- means at said RF/IF port for terminating said diodes and said transmission line means such that said diodes are operatively coupled in parallel across said LO port.
A mixer having a balanced LO port and an RF/IF port comprising:
- first and second transmission line means, each of said transmission line means having an outer shield means and at least one inner conductor;
- first and second diodes symmetrically coupled in series as a part of at least one of the inner conductors of each said first and second transmission line means respectively;
- means at said LO port for coupling said first diode with said outer shield means of said second transmission line means and said second diode with said outer shield means of said first transmission line means;
- and
- means at said RF/IF port for terminating said diodes and said outer shield means such that said diodes are operatively coupled in parallel across said LO port.
Dependencies are inferred from the claim text.