Planar broadband FET balun
AssigneeHughes Aircraft Company
InventorsCheng P. Wen, Wing Yau
Life of this patent
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Abstract
Three active FET baluns, using resonant, reactive and resistive/reactive compensation are disclosed suitable for monolithic implementation. A single balanced mixer configuration including a resistive/reactive active FET balun coupled with a pair of single ended FET mixers in a push pull configuration is disclosed which is also suitable for monolithic implementation.
Claims18
A balun circuit for hybrid monolithic implementation, comprising:
- an active monolithic device comprising an FET having a gate electrode, a source electrode and a drain electrode, wherein the gate is coupled to an input terminal and the source and drain electrodes are coupled to a pair of output terminals;
- and
- means for compensating the active device comprising a reactive impedance coupled between at least one of the source and drain and ground, wherein the reactive impedance is chosen such that the voltage at the source is equal in magnitude to the voltage at the drain and is substantially 180 degrees out of phase within an operating bandwidth.
A balun circuit for hybrid and monolithic implementation, comprising:
- an active device comprising an FET having a gate electrode, a source electrode and a drain electrode, wherein the gate is coupled to an input terminal and the source and drain electrodes are coupled to a pair of output terminals;
- and
- means for compensating the active device comprising a resonant impedance coupled between at least one of the source and drain and the gate, wherein the resonant impedance is chosen such that the voltage at the source is equal in magnitude to the voltage at the drain and is substantially 180 degrees out of phase within an operating bandwidth.
A balanced mixer circuit for monolithic implementation, comprising a balun circuit wherein the balun circuit includes an active monolithic device comprising an FET having a gate electrode, a source electrode and a drain electrode, wherein the gate is coupled to an input terminal and the source and drain electrodes are coupled to a pair of output terminals;
- and means for compensating the active device comprising a reactive impedance coupled between at least one of the source and drain and ground, wherein the reactive impedance is chosen such that the voltage at the source is equal in magnitude to the voltage at the drain and is substantially 180 degrees out of phase within an operating bandwidth;
- and
- a resistive mixer coupled to the output terminals.
Dependencies are inferred from the claim text.