Abstract: The various embodiments of the present invention provide improved methods and circuits for generating millimeter-wave oscillations. Generating millimeter-wave oscillations may involve providing a semiconductor device comprising at least two terminals and a polar heterojunction formed from two semiconductor materials. A voltage bias may be applied to at least two terminals of the device in which the voltage enhances a two-dimensional electron gas (2DEG) layer at the polar heterojunction and produces a sharply-peaked but spatially-localized electric field within the 2DEG with a large longitudinal component, wherein the longitudinal component of the electric field serves as a nucleation site for a plurality of propagating dipole domains observable as a plurality of self-sustaining millimeter-wave oscillations.
Type:
Grant
Filed:
January 31, 2011
Date of Patent:
February 17, 2015
Assignee:
Georgia Tech Research Corporation
Inventors:
Paul Douglas Yoder, Sriraaman Sridharan
Abstract: An electrical circuit generates an oscillating signal that produces reduced electromagnetic interference by way of modulation of the frequency of the oscillating signal within a specified frequency range. A randomized signal generator creates a randomized signal, which is then used to drive a frequency range converter that is employed to produce a frequency modulation signal. The current state of the frequency modulation signal is based on the current state of the randomized signal, with the converter limiting the current state of the frequency modulation signal so that the oscillating signal will only operate within the specified frequency range. A variable frequency oscillator then generates the oscillating signal whose frequency is based on the current state of the frequency modulation signal.
Abstract: A radial electron-beam-breakup transit-time oscillator (RBTO) provides a compact high power microwave generator. The RBTO includes a coaxial vacuum transmission line having an outer conductor and an inner conductor. The inner conductor defines an annular cavity with dimensions effective to support an electromagnetic field in a TEM.sub.00m mode. A radial field emission cathode is formed on the outer conductor for providing an electron beam directed toward the annular cavity electrode. Microwave energy is then extracted from the annular cavity electrode.
Type:
Grant
Filed:
July 30, 1997
Date of Patent:
September 8, 1998
Assignee:
The Regents of the University of California
Abstract: A circuitless particle beam device for relatively high frequency amplifier r oscillator applications that eliminates the requirement for an internal RF slow wave structure. A circularly polarized RF energy wave propagates on a relatively high density particle beam within an oversized waveguide and interacts with the beam which exhibits a relatively high dielectric constant. The high density beam acts as an active dielectric waveguide serving the dual purpose of a slow wave circuit and amplification source, and accordingly guides and amplifies the RF energy when a condition of beam and wave synchronism is met.
Type:
Grant
Filed:
April 17, 1981
Date of Patent:
June 21, 1983
Assignee:
The United States of America as represented by the Secretary of the Army
Inventors:
Charles M. DeSantis, Louis J. Jasper, Jr.
Abstract: A reflecting electron tube for producing high-power, high-frequency, monoomatic microwave pulses includes an anode which produces little or no ion flux when struck by electrons emitted from a cathode, and requires no applied, external magnetic field. An anode support holding the anode and a cathode shank which supports the cathode are positioned within a vacuum chamber such that the anode is closely spaced from the cathode. The anode support is connected to a pulsed high-voltage supply located external to the chamber. The anode is formed from a material which does not produce a significant amount of ion flux but does permit electrons emitted from the cathode to oscillate through the anode. Electrons oscillating in phase bunch together within the potential well of the system and emit microwave radiation.
Type:
Grant
Filed:
March 22, 1978
Date of Patent:
April 17, 1979
Assignee:
The United States of America as represented by the Secretary of the Navy
Inventors:
Christos A. Kapetanakos, Phillip A. Sprangle, Redge A. Mahaffey, Jeffry Golden