Ultrahigh frequency oscillator utilizing transmission line tunable resonant circuits

Claim 2

An oscillator having means for suppressing spurious oscillation at a frequency above the desired frequency range comprising: a transistor having base, emitter and collector electrodes; a transmission line comprising an elongated conductive section disposed on a dielectric supporting plate and overlying a conductive ground plane area on the opposite side of said plate, said transmission line being susceptible to spurious resonance above the desired frequency of operation which resonance is characterized by a voltage null at a particular location on said transmission line; first means coupling the collector electrode of said transistor to said location on said transmission line; and feedback means interconnecting said base, collector, and emitter electrodes to sustain oscillation at a frequency determined by said transistor line, said feedback means including an impedance element connected from one of said base and emitter electrodes to said ground plane at a point opposite the location of said voltage null on said transmission line.

Claim 3

An oscillator as defined in claim 1 wherein said first coupling means and said impedance element are capacitors.

Claim 4

An oscillator as defined in claim 2 wherein said supporting plate is a dielectric plate having a high permeability.

Claim 5

An oscillator as defined in claim 3 wherein said capacitor comprising said first coupling means is formed of conductive areas on said supporting plate.

Claim 6

An oscillator as defined in claim 4 wherein said supporting plate is formed from an aluminum oxide compound.

Claim 7

A UHF oscillator having means for suppressing spurious oscillation at a frequency above the desired frequency range comprising: an active device having a first and a second electrode; a transmission line comprising first and second aligned conductive sections disposed on a dielectric plate and overlying a conductive ground plane area on the opposite side of said plate, one end of said first section electrically connected to said ground plane; said transmission line being susceptible to spurious resonance above the desired frequency of operation which resonance is characterized by a voltage null at a particular location on said second section; first means coupling the first electrode of said device to said location on said transmission line; and feedback means coupled to said device to sustain oscillation at a frequency determined by said transmission line, said feedback means including an impedance element connected from the second electrode of said device to said ground plane at a point opposite the location of said voltage null on said second section.

Claim 8

A UHF oscillator having means for suppressing spurious oscillation at a frequency above the desired frequency range comprising: an active device having a first and a second electrode; a transmission line comprising first and second aligned conductive sections disposed on a dielectric plate and overlying a conductive ground plane area on the opposite side of said plate, one end of said first section electrically connected to said ground plane; said transmission line being susceptible to spurious resonance above the desired frequency of operation which resonance is characterized by a voltage null at a particular location on said second section; first means coupling the first electrode of said device to said location on said transmission line; and feedback means coupled to said device to sustain oscillation at a frequency determined by said transmission line, said feedback means including an impedance element connected from the second electrode of said device to said ground plane at a point opposite the location of said voltage null on said second section.

Claim 9

A UHF oscillator as defined in claim 6 wherein said ground plane area includes a window exposing said dielectric plate and a conductive area disposed within said window which cooperates with another conductive area on said dielectric plate to provide a circuit capacitance for said oscillator.

Claim 10

An oscillator of the type including an active device having a feedback network coupled to said device electrodes, comprising: a transmission line comprising an elongated conductive section disposed on a dielectric supporting plate and overlying a conductive ground plane area on the opposite side of said plate; said ground plane conductive area including a window exposing said dielectric supporting plate; and a first conductive area disposed within said ground plane window forming a part of said feedback network.

Claim 11

An oscillator of the type including an active device having a feedback network coupled to said device electrodes, comprising: a transmission line comprising an elongated conductive section disposed on a dielectric supporting plate and overlying a conductive ground plane area on the opposite side of said plate; said ground plane conductive area including a window exposing said dielectric supporting plate; and a first conductive area disposed within said ground plane window forming a part of said feedback network.

Claim 12

An oscillator as defined in claim 8 including a second conductive area disposed within said ground plane window.

Claim 13

An oscillator as defined in claim 9 wherein said active device is a three terminal device having a first, a second and a control electrode, and Said first and said second conductive areas provide a capacitance interconnecting said first and said second device electrode.

Claim 14

An oscillator as defined in claim 10 including a third conductive area disposed on said dielectric plate such that said first and said second conductive areas overlie said third conductive area on the opposite side of said plate, said opposite disposed conductive areas cooperating to provide a capacitance coupling said device first electrode and said conductive section.

Claim 15

An oscillator as defined in claim 11 wherein one of said first and said second conductive areas cooperates with the adjacent area of said ground plane to provide a capacitance connecting said device second electrode and said ground plane.

Claim 16

An oscillator as defined in claim 12 including a variable capacitance device coupled to said transmission line such that said oscillator is tunable across a band of frequencies ranging from 517 MHz. to 931 MHz.