Abstract:
High quality epitaxial layers of monocrystalline materials can be grown overlying monocrystalline substrates such as large silicon wafers by forming a compliant substrate for growing the monocrystalline layers. One way to achieve the formation of a compliant substrate includes first growing an accommodating buffer layer on a silicon wafer. The accommodating buffer layer is a layer of monocrystalline oxide spaced apart from the silicon wafer by an amorphous interface layer of silicon oxide. The amorphous interface layer dissipates strain and permits the growth of a high quality monocrystalline oxide accommodating buffer layer. The accommodating buffer layer is lattice matched to both the underlying silicon wafer and the overlying monocrystalline material layer. Any lattice mismatch between the accommodating buffer layer and the underlying silicon substrate is taken care of by the amorphous interface layer. A portion of the accommodating buffer layer may be used to form a dielectric for a dielectric resonance. In addition, formation of a compliant substrate may include utilizing surfactant enhanced epitaxy, epitaxial growth of single crystal silicon onto single crystal oxide, and epitaxial growth of Zintl phase materials. The use of monocrystalline dielectric material as an overlying layer is disclosed to facilitate the fabrication of on chip high frequency communications devices such as dielectric resonators with direct interface to compound semiconductor material in the integrated circuit. The provision of on chip resonators through the use of dielectric material in the form of a monocrystalline layer facilitates high frequency communications circuits on a single integrated circuit that may include materials such as thin film crystalline materials used as resonators including dielectric resonators.
Abstract:
An RF/Microwave oscillator is disclosed that has the high-Q, low-loss, and phase noise performance of a DRO, without the need of a dielectric resonator to achieve such performance. The RF/Microwave oscillator includes a field effect transistor having a drain coupled to an output circuit, a source coupled to a series feedback circuit, and a gate coupled to a resonator circuit. Each of these circuits are comprised of cascaded pairs of coupled transmission lines designed to resonate at the operating frequency of the oscillator. The RF/Microwave oscillator may also include a frequency-adjustable bias circuit, a frequency-adjustable FET gate return, and a frequency tuning circuit.
Abstract:
A radio frequency converter includes a plurality of signal paths for simultaneously processing two RF signals in the same band but with different polarizations, each of which includes a mixer and an oscillator. A common resonator is connected to the frequency control terminal of each of the oscillators and the oscillators work in a push-push configuration.
Abstract:
A multiple-frequency local oscillator for providing an LO signal at one of a multiple of predetermined resonant frequencies associated with a number of resonators is disclosed. It includes a number of LO input ports for coupling to a plurality of resonators, respectively, each resonator having a predetermined resonant frequency; the local oscillator is controlled to selectively provide at its LO output port an output LO signal at any one of the resonant frequencies.
Abstract:
A split dielectric resonator having two preferably half cylindrical dielectric elements is used to stabilize an oscillator operating at microwave frequencies. Fine tuning may be achieved by means of a tuning screw which has a thermal expansion coefficient between those of the dielectric elements and electrically conductive supporting walls. Additionally, fine tuning may be achieved by offsetting the two elements from each other within a horizontal or vertical plane. This oscillator can also be configured as an accelerometer or pressure or displacement sensor by substituting a movable deflecting member for the supporting wall.
Abstract:
A Gaussian-beam oscillator for microwave and millimeter wave comprising a negative resistance amplifier circuit which produces and amplifies a high-frequency signal, a resonator consisting of a pair of reflecting mirrors, which consist of a spherical mirror and a planar mirror or two spherical mirrors, and a wave path which transmits the high-frequency signal between said resonator and said negative resistance amplifier circuit, one reflecting mirror of said resonator having an electromagnetic wave coupling region constituted as a circular partially transparent mirror surface region having its center on the optical axis, the other reflecting mirror having a strip element provided at the center of the optical axis and on the rear surface of said strip element having a coupling region for coupling with said wave path, said one reflecting mirror constituting said resonator and having the electromagnetic wave coupling region having a higher reflectance than the reflectance of the other reflecting mirror.
Abstract:
A microwave oscillator circuit is provided for decreasing the number of passive elements such as inductance, etc. in microwave oscillators and frequency doublers. A microwave oscillator circuit is connected to a resonator circuit generating a signal at a frequency f, and produces at its output a signal of frequency nf, and comprises a first field effect transistor having a gate connected to the resonator circuit, a second field effect transistor whose source/drain path is connected in series with the source/drain path of the first field effect transistor and a connecting circuit for coupling either the gate or source of the first field effect transistor to the gate of the second field effect transistor. A signal of frequency nf is output at a node corresponding to a connection point between the source of the first field effect transistor and the drain of the second field effect transistor.
Abstract:
An oscillating circuit includes a substrate, a FET formed on the substrate, a series feedback capacitor connected to the source of the FET, a microstrip line formed on the substrate and connected to the gate of the FET, and a dielectric resonator which is electromagnetically coupled to the microstrip line. The dielectric resonator is located near the microstrip line.
Abstract:
A push-push broadband dielectric resonator oscillator circuit that operates in the K and Ka band frequency range has two oscillator circuits that oscillate at the same fundamental frequency. An antiphaseal relationship is maintained between the two oscillators through the use of a dielectric resonator and the desired frequency is obtained by vectorially combining the output signals of the two oscillators that have the antiphase relationship to obtain an output frequency that is twice the fundamental frequency of operation of each of the individual dielectric resonator oscillator circuits.
Abstract:
In a dielectric resonator controlled oscillator with frequency multiplication, a line (12) has an open end and another end connected to a gate electrode of an FET (11) with a dielectric resonator (13) electromagnetically coupled to the line at a location along a total length of the line. The total length is selected to make a combination of the line and the dielectric resonator have a substantially zero impedance for a higher harmonic frequency when seen from the gate electrode. More specifically, the total length is selected so as to be equal to about three quarters of a wavelength which a frequency multiplied oscillation, such as a frequency doubled oscillation, has in the line. The location is selected so as to optimize the oscillator for a fundamental oscillation of a fundamental frequency determined by the dielectric resonator.