Voltage controlled oscillators including tunable dielectric devices

A voltage controlled oscillator comprising:

• an active element having a first connection point for connection to a voltage source and an output connection point;
• a tunable resonator including a first microstrip line connected in series with a first voltage tunable dielectric device, the tunable resonator connected to an input of the active element;
• a first circuit branch including a second microstrip line connected in series with a second voltage tunable dielectric device, the first circuit branch connected to the active element;
• and
• a tuning voltage controller for supplying a control voltage to the first voltage tunable dielectric device to control the frequency of an oscillating voltage at the output connection point, wherein the tuning voltage controller also supplies a second control voltage to the second voltage tunable dielectric device, the voltage controlled oscillator further comprising:
• a first DC isolation circuit connected between the tuning voltage controller and the first tunable dielectric device;
• and
• a second DC isolation circuit connected between the tuning voltage controller and the second tunable dielectric device.

A voltage controlled oscillator comprising:

• an amplifier having a first connection point for connection to a voltage source and an output connection point;
• a tunable resonator including a first voltage tunable dielectric device, the tunable resonator is connected between an input of the amplifier and a common point;
• a phase shifter including a second voltage tunable dielectric device, the phase shifter is connected between an output of the amplifier and the tunable resonator;
• and
• a tuning voltage controller for supplying a control voltage to the first voltage tunable dielectric device to control the frequency of an oscillating voltage at the output connection point, the voltage controlled oscillator further comprising:
• a first DC isolation circuit connected between the tuning voltage controller and the first voltage tunable dielectric device;
• and
• a second DC isolation circuit connected between the tuning voltage controller and the second voltage tunable dielectric device.

A voltage controlled oscillator comprising:

• a transistor having a collector connected to a voltage source and an output connection point;
• a tuning controller;
• a tunable resonator including a first voltage tunable dielectric capacitor, the tunable resonator is connected between the tuning controller and a base of the transistor;
• a tunable bypass circuit including a second voltage tunable dielectric capacitor, the tunable bypass circuit is connected between the tuning controller and an emitter of the transistor;
• said tuning controller is capable of supplying two different tuning voltages, one tuning voltage is supplied to the first voltage tunable dielectric capacitor and the second tuning voltage is supplied to the second voltage tunable dielectric capacitor to control the frequency of an oscillating voltage at the output connection point.

A voltage controlled oscillator comprising:

• an amplifier connected to a voltage source;
• a tunable resonator including a first voltage tunable dielectric capacitor;
• a tunable phase shifter including a second tunable dielectric capacitor, the tunable phase shifter is connected between an output of the amplifier and the tunable resonator which is connected between an input of the amplifier and the tunable phase shifter;
• and
• a tuning controller for supplying tuning voltages to the first and second voltage tunable dielectric capacitors to control the frequency of an oscillating voltage at the output of the amplifier, the voltage controlled oscillator further comprising:
• a first DC isolation circuit connected between the tuning voltage controller and the first voltage tunable dielectric capacitor;
• and
• a second DC isolation circuit connected between the tuning voltage controller and the second voltage tunable dielectric capacitor.