Oscillator with switched reactance resonator for wide bandwidth and serial bias connections for low power

Claim 2

An oscillator comprising: means for supplying an amplifier biasing current; an amplifier having an input for receiving feedback and an output for energizing an oscillation signal relative to a common potential so that the oscillation signal oscillates within a range of frequencies less than a maximum frequency of oscillation, said amplifier being biased by the amplifier biasing current of said supplying means; a resonator comprising a plurality of reactive impedance devices, said resonator being coupled to the amplifier input and to the amplifier output; and a switching section comprising a first PIN diode having ON and OFF modes, the first PIN diode being coupled to said amplifier and to said resonator so that when the first PIN diode is in the ON mode the amplifier biasing current of said supplying means flows through the first PIN diode and said resonator exhibits a first resonant frequency, and when the first PIN diode is in the OFF mode the first PIN diode electrically switches one of the reactive impedance devices relative to said resonator so that said resonator exhibits a second resonant frequency.

Claim 3

An oscillator as claimed in claim 1 wherein said amplifier is operationally biased with an amplifier biasing current of less than 3 milliamperes.

Claim 4

An oscillator as claimed in claim 2 wherein said amplifier is capable of energizing the oscillation signal at a frequency of greater than 350 MHz.

Claim 5

An oscillator as claimed in claim 1 where said amplifier comprises a differential amplifier having first and second transistors, each having collector, emitter, and base nodes, and each exhibiting a gain-bandwidth-product at least three times the maximum frequency of oscillation, wherein the first and second transistor emitters are coupled together, the first transistor collector couples to the first PIN diode and to said resonator, and the second transistor base couples to said resonator.

Claim 6

An oscillator as claimed in claim 1 wherein said resonator comprises: an inductive device having a first tap point, said inductive device being coupled between the amplifier output and a common potential, and the first tap point being coupled to the amplifier input; a first capacitive device having first and second nodes, said first capacitive device being coupled in parallel with the first PIN diode, and said first capacitive device first node being coupled to the amplifier output; and a second capacitive device coupled between the second node of said first capacitive device and the common potential.

Claim 7

An oscillator as claimed in claim 5 wherein said second capacitive device is a varactor diode.

Claim 8

An oscillator as claimed in claim 6 wherein said first capacitive device is a varactor diode.

Claim 9

An oscillator as claimed in claim 5 additionally comprising a buffer, and wherein the inductive device of said resonator additionally comprises a second tap point, said buffer coupled to the second tap point for providing the oscillator output and isolating said amplifier and resonator from varying loading conditions.

Claim 10

An oscillator as claimed in claim 1 wherein said supplying means comprises a voltage regulator coupled to said first PIN diode.

Claim 11

An oscillator as claimed in claim 9 wherein said voltage regulator additionally couples to said resonator and outputs the oscillation signal from the oscillator so that said amplifier and resonator are isolated from varying loading conditions.

Claim 12

An oscillator comprising: an amplifier having an output and an input; a resonator having a plurality of reactive impedance devices to produce a plurality of resonant frequencies, said resonator being coupled to said amplifier input and output so that an oscillation signal is produced relative to a common potential and the oscillation signal is energized by said amplifier; and means, coupled to said amplifier and to said resonator, for regulating DC supply voltage and for simultaneously buffering the oscillation signal, said means providing an amplifier biasing current and said ampliier being operationally biased with the amplifier biasing current.

Claim 13

An oscillator comprising: an amplifier having an output and an input; a resonator having a plurality of reactive impedance devices to produce a plurality of resonant frequencies, said resonator being coupled to said amplifier input and output so that an oscillation signal is produced relative to a common potential and the oscillation signal is energized by said amplifier; and means, coupled to said amplifier and to said resonator, for regulating DC supply voltage and for simultaneously buffering the oscillation signal, said means providing an amplifier biasing current and said ampliier being operationally biased with the amplifier biasing current.

Claim 14

As oscillator as claimed in claim 11 additionally comprising a switching section having a PIN diode with ON and OFF modes, the PIN diode being coupled to said amplifier and to said resonator so that when the PIN diode is in the ON mode the amplifier biasing current flows through the PIN diode and said resonator exhibits a first one of the plurality of resonant frequencies, and when the PIN diode is in the OFF mode the PIN diode electrically switches one of the reactive impedance devices relative to said resonator so that said resonator exhibits a second one of the plurality of resonant frequencies.

Claim 15

An oscillator as claimed in claim 12 wherein said resonator comprises: an inductive device having first and second tap points, said inductive device being coupled between the amplifier output and the common potential, the first tap point of said inductive device being coupled to the amplifier input, and the second tap point being coupled to said regulating and buffering means; a first capacitive device having first and second nodes, said first capacitive device being coupled in parallel with said PIN diode, and said first capacitive device first node being coupled to the amplifier output; and a second capacitive device being coupled between the second node of said first capacitive device and the common potential.

Claim 16

An oscillator as claimed in claim 13 wherein said regulating and buffering means comprises: a transistor coupled to the second tap point of said inductive device and coupled to said amplifier; a transformer having primary and secondary windings DC coupled together, said transformer being coupled to said transistor; and means, coupled to said transistor, for supplying a DC reference voltage.

Claim 19

A method as claimed in claim 15 wherein said supplying step additionally comprises the step of buffering the oscillation signal.

Claim 20

An oscillator generating an oscillation signal capable of oscillating relative to a common potential at a plurality of oscillation frequencies less than a maximum frequency of oscillation, said oscillator comprising: a regulator-buffer having, a first transistor, a transformer having primary and secondary windings, the primary and secondary windings being DC coupled together, the primary winding being connected to the first transistor, and means, coupled to the first transistor, for supplying a DC reference voltage; a switching section having, a PIN diode coupled to said first transistor, and a second transistor having a collector and an emitter, the second transistor collector and emitter being coupled in parallel with said PIN diode; a differential amplifier having third and fourth transistors, each having collector, emitter, and base nodes, and each exhibiting a gain-bandwidth-product of at least three times the maximum frequency of oscillation, wherein the third and fourth transistor emitters are coupled together, and the third transistor collector couples to the PIN diode of said switching section; and a resonator having, an inductive device having first and second tap points, said inductive device being coupled between the collector of the third transistor of said amplifier and the common potential, the first tap point coupled to the base of the fourth transistor of said amplifier, and the second tap point coupled to the first transistor of said regulator-buffer, a first capacitive device having first and second nodes, the first capacitive device coupled in parallel with the PIN diode of said switching section, and a second capacitive device coupled between the second node of the first capacitive deivce and the common potential.

Claim 21

An oscillator generating an oscillation signal capable of oscillating relative to a common potential at a plurality of oscillation frequencies less than a maximum frequency of oscillation, said oscillator comprising: a regulator-buffer having, a first transistor, a transformer having primary and secondary windings, the primary and secondary windings being DC coupled together, the primary winding being connected to the first transistor, and means, coupled to the first transistor, for supplying a DC reference voltage; a switching section having, a PIN diode coupled to said first transistor, and a second transistor having a collector and an emitter, the second transistor collector and emitter being coupled in parallel with said PIN diode; a differential amplifier having third and fourth transistors, each having collector, emitter, and base nodes, and each exhibiting a gain-bandwidth-product of at least three times the maximum frequency of oscillation, wherein the third and fourth transistor emitters are coupled together, and the third transistor collector couples to the PIN diode of said switching section; and a resonator having, an inductive device having first and second tap points, said inductive device being coupled between the collector of the third transistor of said amplifier and the common potential, the first tap point coupled to the base of the fourth transistor of said amplifier, and the second tap point coupled to the first transistor of said regulator-buffer, a first capacitive device having first and second nodes, the first capacitive device coupled in parallel with the PIN diode of said switching section, and a second capacitive device coupled between the second node of the first capacitive deivce and the common potential.