US 3,943,463 A · Tunable oscillator/amplifier circuit for millimeter-wave diodes

Abstract

Disclosed is microwave oscillator or amplifier circuitry which is tunable over a wide bandwidth and which includes an improved variable loading on a negative resistance semiconductor diode, such as an IMPATT diode. This loading is provided in mutually perpendicular directions closely adjacent the diode. In one direction, a DC bias connection is mounted together with an adjustable coaxial filter thereon, and this filter serves as a series tuning element for the diode. A movable short is mounted for adjustment in a direction perpendicular to that of the above coaxial filter and provides parallel tuning for the diode. These series and parallel tuning elements are operative to match the real and imaginary components of the diode impedance to the real and imaginary components of the load impedance, respectively, at a particular operating frequency, thereby maximizing the power transfer and the DC to RF conversion efficiency of the circuitry. For ease of frequency adjustment, all of the frequency dependent parameters of the circuitry are contained in a removable and replaceable insert which fits securely into the waveguide housing.

Claims12

Dependent claims

A tunable microwave structure for sustaining oscillations or achieving amplifications, including in combination:

a. a hollow waveguide structure,
b. a negative resistance diode mounted adjacent one wall of said hollow waveguide structure;
c. said structure having an opening in another wall thereof through which a DC bias connector is centrally disposed and makes electrical contact to said diode for providing a DC bias voltage thereto;
and
d. filter means comprising a hollow member coaxial with said bias connector and disposed thereon within said opening, said member and said opening in said waveguide structure defining a cavity around said DC bias connector, whereby the position of said member on said connector establishes the loading on said diode and said bias connector serves as both the DC electrical connection for said diode and a slide member for said filter.

2 more elements

In a microwave or millimeter wave oscillator or amplifier having a negative resistance diode mounted on one wall of a waveguide structure and serially connectable via a bias pin to a DC supply, the improvement comprising:

a hollow filter member positioned in an opening in a waveguide wall of said structure opposite said wall on which said diode is mounted and slidable on said bias pin toward and away from from said diode for varying the series loading on said diode, whereby the size and number of parts necessary to accomplish such loading is minimized.

Dependencies are inferred from the claim text.

Tunable oscillator/amplifier circuit for millimeter-wave diodes

Life of this patent

Tunable oscillator/amplifier circuit for millimeter-wave diodes

Life of this patent

Abstract

Claims12