Abstract:
An improved microwave circuit is disclosed for enabling impedance tuning for power coupling in IMPATT diode and other similar oscillator and amplifier circuits. An electrically conductive support plate forming a ground plane is machined to form a channel for slidably receiving an air-stripline transmission line and a resonator therein. An IMPATT diode is positioned within the channel through an opening extending through the support plate generally perpendicular to the channel and is positioned in contact with the resonator. An electrically conductive bias filter is coupled to the resonator and to an adjusting mechanism for moving the resonator along the channel and providing a DC bias to the diode for oscillation. An electrically conductive cover member retains a spring biased electrically non-conductive projection for maintaining the resonator in contact with the diode. By controlling the adjusting mechanism and the position of the air-stripline within the channel, the real and imaginary parts of diode impedance can be adjusted to change the frequency and match the impedance of the diode to a conventional transmission line or coupling circuit.
Abstract:
A source of millimeter waves adjustable in power and frequency and embodied as a cylindrical waveguide one end of which is provided with a movable piston and the other end with a directive antenna generally a radiating horn. Between the ends is tapped a cylindrical waveguide branch in which slides a sub-assembly carrying a radiating module containing an oscillating diode. The position of the module affects the power and the frequency of oscillation of the source and the position of the movable piston acts on the power emitted by the radiating horn.
Abstract:
A compact solid-state oscillator-transmitter which includes a transistor within a small can defining a tuning cavity. The can is electrically connected in the output circuit to present a capacitance which may be varied by manual adjustment of a tuning screw so that the effective output impedance, including parasitic impedance, has the proper phase angle necessary to permit oscillation at the desired frequency. The can is also utilized to shield radiation of radiofrequency conducting circuit components, to secure the components, and to protect the same against adverse environmental influences. A probe is provided to pick up oscillatory signal energy in the cavity and is utilized as an antenna when transmitting the produced signal.