摘要:
A microwave mixer suitable for millimeter wave radar applications. A semi-insulating gallium arsenide dielectric waveguide structure contains an embedded planar doped barrier (PDB) structure as a non-linear mixing element. The local oscillator (LO) signal is guided to the PDB structure via a coplanar type waveguide. The radio frequency (RF) signal is guided to the PDB structure via an image guide and a microstrip circuit serves to transmit the intermediate frequency (IF).
摘要:
A passive millimeter wave image guide power limiter comprising a length ofielectric transmission line or waveguide for millimeter wave frequencies located on a relatively thin conductive ground plane forming thereby an image guide and including a planar doped barrier diode structure formed in the dielectric transmission line with the planar doped barrier structure being integrally grown in a slot milled in the constituent material, i.e. gallium arsenide, of the waveguide transversely across the width dimension thereof so as to be oriented perpendicular to the flow of RF power being propagated along its length dimension. The planar doped barrier structure becomes conductive at a predetermined power level to reflect any further incident RF power back toward the power source.
摘要:
A dual Gunn self-oscillating mixer is shown which can mix signals in the range substantially without introducing any noise and with high input signal power handling capacity and with higher output mixed signal power than conventional, owing to boosted power from more than one microwave cavity. The device is comprised of two cavities and connected by a 180.degree. phase shift coax line for injection locking, or a cavity wall hole in yet another embodiment. The device handles larger power levels without burning out as compared to conventional type mixer devices such as Schottky barrier diodes having nearly 30 times the burnout susceptibility.
摘要:
Disclosed is a millimeter wave bulk effect RF power limiter consisting of alanar PIN diode formed on a gallium arsenide (GaAs) substrate which also comprises the waveguide structure for RF energy in the 60-300 GHz range. The PIN diode is comprised of a wedge of intrinsic type semiconductor material formed across the top surface of the substrate and having mutually opposing regions of p and n type semiconductor material fabricated in the side edges of the wedge to which is attached planar beam leads. With suitable electrical operating potentials applied to the PIN diode avalanche breakdown occurs at a critical RF power level which acts to limit the flow of RF energy flow in the structure past the location of the PIN diode. Such a structure permits the device to be integrated into the front end sections of receivers utilized in communications, missile guidance and radar systems operable in the millimeter and sub-millimeter frequency range.
摘要:
A dielectric waveguide power limiter for a self-oscillating mixer operatingn millimeter-wave frequencies. The limiter includes a high resistivity silicon dielectric waveguide and a Gunn oscillator. A plurality of dielectric resonators each including a high uniaxial anisotropy ferrite sphere embedded therein are positioned between the power input end of the waveguide and the Gunn oscillator.
摘要:
A single planar doped barrier diode is grown by the selective deposition of gallium arsenide using molecular beam epitaxy (MBE) in the center of a gallium arsenide dielectric waveguide member mounted on a ground plane. The waveguide member includes two portions which extend in opposite directions and terminating in respective metal to dielectric waveguide transition sections which are coupled to an RF input signal and local oscillator signal, respectively. The planar doped barrier diode operates as an intrinsic subharmonic mixer and accordingly the local oscillator signal has frequency of one half the input signal frequency. An IF output signal is coupled from the mixer diode to a microstrip transmission line formed on an insulating layer fabricated on the ground plane. Dielectric waveguide isolators are additionally included on the dielectric waveguide segments to mutually isolate the input signal and local oscillator signal. A monolithic form of circuit fabrication is thus provided which allows the planar doped barrier mixer circuit to be extremely small and the cost of mass producing such a circuit to be very economical.
摘要:
A radiation measurement means is shown which has the capability of detect radiation in both the millimeter wave, and the infrared, frequency regions. A basic self-oscillating Gunn diode is enclosed in a donut shaped silicon ring. The presence of infrared energy will create holes and electrons in the silicon material, altering its conductivity, and lower the power of oscillation. The realized drop in oscillating power identifies the infrared. Millimeter wave radiation is detected because an intermediate frequency is generated as the Gunn diode operates as a self-oscillating mixer of the new different frequency with its own oscillating frequency. Thus it is possible to detect signals from both ranges, in a single device.
摘要:
A triple Gunn diode self-oscillating mixer system is shown which can mix nals in the VHF range substantially without introducing any noise and with high input signal power handling capacity and with higher output mixed signal power than conventional, owing to boosted power from more than one microwave cavity. The device is comprised of three self-oscillating Gunn diode cavities connected by 180.degree. phase shift coax lines for injection locking. The device handles larger power levels without burnout as compared to conventional mixer devices such as Schottky barrier diodes having nearly 30 times less burnout capacity.
摘要:
A magnetically tuned band reject filter for millimeter wave frequencies crising a barium ferrite sphere embedded in the upper surface of a semi-insulating gallium arsenide waveguide transmission line element located on a conductive ground plane and forming thereby an image guide. A pair of high energy rare earth permanent magnets are located on the upper and lower surfaces of the waveguide element at the location of the ferrite sphere with a single tuning coil surrounding both the magnets and the waveguide and operates to bias the ferrite sphere for selective absorption of signals propagating along the transmission line. With the magnetically tuned ferrite sphere located therebetween, both an input signal and a local oscillator signal, for example, are coupled to one end of the waveguide element while receiving electronics apparatus, such as a Schottky barrier diode mixer, is located at the other end of the waveguide element.
摘要:
A monolithic millimeter wave balanced mixer in which two Schottky barrier odes receive combined power from. Two Schottky barrier diodes receive combined power from an RF source and local oscillator in a gallium arsenide image guide. The diodes produce an intermediate frequency which is directed to a microstrip low pass filter.