132 results about "Pulsed radiofrequency" patented technology

A cardiac assist device containing a device for connecting the cardiac assist device to a heart, for furnishing electrical impulses from the cardiac assist device to the heart, for ceasing the furnishing of electrical impulses to the heart, for receiving pulsed radio frequency fields, for transmitting and receiving optical signals, and for protecting the heart and the cardiac assist device from currents induced by the pulsed radio frequency fields. The cardiac assist device contains a control circuit comprised of a parallel resonant frequency circuit.

A medical device containing a device for connecting the medical device to a substrate, for furnishing electrical impulses from the medical device to the substrate, for ceasing the furnishing of electrical impulses to the substrate, for receiving pulsed radio frequency fields, for transmitting and receiving optical signals, and for protecting the substrate and the medical device from currents induced by the pulsed radio frequency fields. The medical device contains a control circuit comprised of a parallel resonant frequency circuit.

A method and system is provided for detecting and characterizing pulsed threat radar emitters through heavy in-band interference. System includes an advanced digital signal processing method provides spatial and temporal interference cancellation, super-resolution direction-finding, and high resolution spectrum analysis techniques. The system receives the digitized output of a discriminator bank and produces highly accurate threat pulse radio frequency estimates. The invention further provides a two-channel configuration for a DF subsystem, to perform adjacent-beam direction-finding through severe interference environments. The invention provides increased sensitivity, increased frequency accuracy, and up to 40 dB of increased interference look-through capability in ES system but remains transparent to ES system functioning and to ES system operators.

The present invention relates to a method for treating a nervous symptom or condition in a subject with a pulsed-radiofrequency stimulation system with a low voltage to overcome the disadvantages of the known related stimulation systems.

The present invention determines the resonant frequency of a wireless sensor by adjusting the phase and frequency of an energizing signal until the frequency of the energizing signal matches the resonant frequency of the sensor. The system energizes the sensor with a low duty cycle, gated burst of RF energy having a predetermined frequency. The system receives the ring down response of the sensor and determines the resonant frequency of the sensor, which is used to calculate a physical parameter. The system uses a pair of phase locked loops to adjust the phase and the frequency of the energizing signal. The system identifies false locks by detecting an unwanted beat frequency in the coupled signal, as well as determining whether the coupled signal exhibits pulsatile characteristics that correspond to a periodic physiological characteristic, such as blood pressure.

The present invention relates generally to a radiofrequency reactor for use in thermally recovering oil and related materials. The radiofrequency reactor includes a radiofrequency antenna configured to be positioned within a well, where the well is provided within an area in which crude oil exists in the ground. The radiofrequency antenna includes a cylindrically-shaped radiating element for radiating radiofrequency energy into the area in which crude oil exists. The cylindrically-shaped radiating element is configured to allow passage of fluids there through. The radiofrequency reactor also includes a radiofrequency generator electrically coupled to the radiofrequency antenna. The radiofrequency reactor is operable to control the radiofrequency energy generated.

An electrosurgical instrument for delivering radiofrequency (RF) electromagnetic (EM) energy and microwave frequency EM energy from a coaxial feed cable through an instrument tip into tissue. The instrument tip comprises a dielectric body separating first and second conductive elements, which act as active and return electrodes to convey the RF EM radiation by conduction, and as an antenna to radiate the microwave EM radiation. The instrument also has a fluid feed incorporated into its tip, e.g. in an additional dielectric element mounted on the underside of the tip, for delivering fluid. The delivered fluid may be a gas plasma to assist treatment or a liquid to plump up a tissue region before treatment. The instrument may fit in an endoscope.

An apparatus and method for determining a parameter of interest of a formation composed of carbonate rock. A nuclear magnetic resonance (NMR) sensor assembly produces a pulsed RF field designed for obtaining measurements indicative of the parameter of interest of the formation. A downhole processor processes the measurements for obtaining BVI and BVM using a cutoff time based on classification of the carbonate. Further processing is done to estimate the permeability of the carbonate.

This disclosure describes systems, methods, and apparatus for pulsed RF power delivery to a plasma load for plasma processing of a substrate. In order to maximize power delivery, a calibration phase using a dummy substrate or no substrate in the chamber, is used to ascertain a preferred fixed initial RF frequency for each pulse. This fixed initial RF frequency is then used at the start of each pulse during a processing phase, where a real substrate is used and processed in the chamber.

A method of fabricating a gate of a transistor device on a semiconductor substrate, includes the steps of placing the substrate in a vacuum chamber of a plasma reactor and introducing into the chamber a process gas that includes oxygen while maintaining a vacuum pressure in the chamber. An oxide insulating layer on the order of several Angstroms in thickness is formed at the surface of the substrate by generating a plasma in a plasma generation region within the vacuum chamber during successive “on” times, and allowing ion energy of the plasma to decay during successive “off” intervals separating the successive “on” intervals, the “on” and “off” intervals defining a controllable duty cycle. During formation of the oxide insulating layer, the duty cycle is limited so as to limit formation of ion bombardment-induced defects in the insulating layer, while the vacuum pressure is limited so as to limit formation of contamination-induced defects in the insulating layer. A conductive gate electrode is formed over the insulating layer.

The invention discloses a microwave scattering property test system based on a vector network analyzer. The microwave scattering property test system comprises the vector network analyzer, an antenna and a main control computer, wherein the vector network analyzer is used for generating a pulse radio frequency signal of a designated parameter under the control of the main control computer; the pulse radio frequency signal is transmitted by the antenna; and the vector network analyzer is also used for carrying out strobe treatment on a target echo signal received by the antenna to obtain microwave scattering property data within a designated area range. The vector network analyzer can be used for generating a narrowband pulse radio frequency signal with the frequency range covering wavebands of L, S, C, X, Ku and Ka; and the position of a strobe gate of a receiver is set by adopting a mode of fixed point test in pulse according to a test object. The microwave scattering property test system disclosed by the invention is convenient for field work and stable in performance and can be used for scattering property test of the ground background and a large-area camouflage net or the target scattering property test.

This invention relates to radiofrequency (rf) cavities and couplers that comprise metallic or dielectric rods to provide specified concentration of field patterns for the operating modes in the interaction region, for applications in particle accelerators, pulsed rf power sources, amplifiers, mode converters and power couplers.

A flexible catheter includes two electrical contacts in a distal region of the catheter and a distal aperture of a hose line. The electrical contacts are connected to a high frequency pulse generator for applying pulsed radio frequency energy for nerve stimulation. A temperature sensor is located in the distal region of the catheter. The flexible catheter is inserted into a region in the spinal canal and the pulsed radio frequency generator is operated, thereby applying pulsed radio frequency energy to a localized region to be treated. The temperature at the distal region of the catheter can also be monitored, and the pulsed radio frequency energy is applied in dependence on the monitored temperature. With the catheter, pain and other medical conditions being related to and influenced by a nervous system are treated.

A system for measuring a position and orientation of an object in flight relative to a reference coordinate system is provided. The system including: three or more illuminating sources, each disposed in a predefined position, the three or more illuminating sources together emitting a plurality of distinct polarized radio frequency signals to provide temporally synchronized, pulsed radio frequency signals that illuminate the object; one or more waveguide cavities disposed on the object for receiving the plurality of distinct polarized radio frequency signals from each of the three or more illuminating sources in flight; and a processor for measuring a time for the plurality of distinct polarized radio frequency signals to propagate from each of the three or more illuminating sources to the one or more waveguide cavities and the level of signal received at the waveguide cavities and to determine a position of the object relative to the three or more illuminating sources based on the measured times and the orientation of the object relative to the reference coordinate system based on the measure levels of received signals.

A method and apparatus for reducing chronic pain in animals by radio frequency (RF) neuromodulation of peripheral nerves of the animal is disclosed. The method, using the disclosed apparatus, comprises the steps of attaching active and dispersive percutaneous probes at respective active and dispersive locations relative to a peripheral nerve of the patient associated with the pain to be reduced; generating a first pulsed RF signal for coupling to the active and dispersive probes to verify the location of the peripheral nerve; and generating a second pulsed RF signal for coupling to the active and dispersive probes to modify propagation of pain sensation in the peripheral nerve without ablation thereof. In one embodiment of the apparatus, the active percutaneous probe includes an RF cannula having a conductive spatulate blade conformably attached to a dorsal side of a curved, blunt-ended tubular tip portion of the RF cannula. In another embodiment of the apparatus, a dispersive percutaneous probe includes a pair of 22 gauge needles connected to ground return conductors. In yet another embodiment of the apparatus, a pulsed RF generator is modified to provide specific outputs adapted to the neuromodulation of peripheral nerves in veterinary patients.

In one aspect, a method for imaging fluid flow and / or perfusion using spin labeling is provided. The method comprises applying a first magnetic gradient sequence at least to a labeling region, applying a first pulsed radio frequency (RF) sequence to the labeling region to label the fluid, the first pulsed RF sequence comprising a first plurality of pulses wherein an amplitude envelope is non-zero, the first plurality of pulses each separated by a respective first plurality of intervals wherein the amplitude envelope is substantially zero, and acquiring at least one first signal emitted from an imaging region a predetermined delay after applying the first pulsed RF sequence.

An apparatus and method for disinfestation of temperature sensitive and other commodities using short duration, high peak power radio frequency pulses and intense electric fields to preferentially induce drift of conduction charges, spot heating and other mortal damage to infesting insects and mites without raising the temperature of the host commodity. A low frequency mode is provided with a frequency range of approximately 10 Hz to 1 MHz and is particularly suited for large batch processing of pallets or field containers. A high frequency mode is also provided that is suited for continuous or small batch processing and uses a preferred frequency range of approximately 1 MHz to 150 MHz. Both modes preferably have an electric field strength of greater than approximately 5 kV / cm and pulse repetition rates of between one pulse and approximately 10 million pulses per second. The method is non-contact, residue free and effective with all biological stages of an infesting insect, mite or other biological pest including egg, pupa, larvae, juvenile and adult forms. The apparatus and methods of the invention are an effective alternative to methyl bromide fumigation that does not leave any toxic residues or damage the cosmetic appearance or flavor of the commodity.

This disclosure describes systems, methods, and apparatus for pulsed RF power delivery to a plasma load for plasma processing of a substrate. In order to maximize power delivery, a calibration phase using a dummy substrate or no substrate in the chamber, is used to ascertain a preferred fixed initial RF frequency for each pulse. This fixed initial RF frequency is then used at the start of each pulse during a processing phase, where a real substrate is used and processed in the chamber.

A method and a device suitable for implementing this method for etching a substrate (10), a silicon body in particular, using an inductively coupled plasma (14) are proposed. For this purpose, a radio-frequency electromagnetic alternating field is generated with an ICP source (13), the alternating field generating an inductively coupled plasma (14) of reactive particles in a reactor (15). The inductively coupled plasma (14) arises by the action of the radio-frequency electromagnetic alternating field on a reactive gas. Furthermore, a device is provided with which a plasma power injected into the inductively coupled plasma (14) via the radio-frequency electromagnetic alternating field with the ICP source (13) is capable of being pulsed so that at least from time to time a pulsed radio-frequency power can be injected into the inductively coupled plasma (14) as a pulsed radio-frequency power. In addition, the pulsed plasma power can be combined or correlated with a pulsed magnetic field and / or a pulsed substrate electrode power.

In one aspect, a method for imaging fluid flow and / or perfusion using spin labeling is provided. The method comprises applying a first magnetic gradient sequence at least to a labeling region, applying a first pulsed radio frequency (RF) sequence to the labeling region to label the fluid, the first pulsed RF sequence comprising a first plurality of pulses wherein an amplitude envelope is non-zero, the first plurality of pulses each separated by a respective first plurality of intervals wherein the amplitude envelope is substantially zero, and acquiring at least one first signal emitted from an imaging region a predetermined delay after applying the first pulsed RF sequence.

The invention discloses a multi-mode multi-band radiofrequency front-end on-board communication system, which comprises a receiving module, a local oscillation module and a transmitting module. A radiofrequency subsystem has wide working frequency band which is between 400MHz and 6GHz, and can support different wireless network services in special environment such as airplane navigation and the like, and communication systems such as 2G, 3G, WLAN, bluetooth and the like. The channel bandwidth changes with the difference of operation modes, wherein the maximum bandwidth can reach 20MHz, the maximum radiofrequency output power is 20dBm, and the noise coefficient of a receiver is less than 9dB.

A method and system for injecting a pulsed radio frequency signal into a fluid-containing system in order to create and propagate an electromagnetic field throughout the fluid-containing system. The electromagnetic field may be used to prevent the formation and build-up of scale in the fluid-containing system and / or to prevent the proliferation of bacteria within the fluid-containing system. The method and system may also be used to inject a pulsed radio frequency signal at a number of points in a fluid-containing system, or to inject a pulsed radio frequency signal to a number of independent fluid-containing systems.

In a unilateral NMR probe for the analysis of a material comprising at least one magnet for generating a constant time-invariant polarization field B0 in the material to be analyzed and current conductors forming a radio frequency oscillation circuit for generating a pulsed radio frequency magnetic excitation field B1 which is superimposed on the polarization field N0 in the material, the circuit conductors are so designed as to provide several adjacent excitation fields B0 with alternatingly oppositely oriented magnetic fields, whereby the current conductors generating each one of the excitation fields have a distance from each other which causes a certain penetration depth in the material to be analyzed and echoes received therefrom provide measurement values which are characteristic for the material being analyzed.

The invention relates to an impedance matching method of a pulse RF power supply and a matching method of plasma equipment. The impedance matching method of the pulse RF power supply comprises a step of (S1) setting an impedance adjusting element at a preset value and setting the pulse frequency of the pulse RF power supply as a preset pulse frequency, (S2) judging whether the preset pulse frequency is larger than a pulse threshold frequency or not, and going to (S3) if so, (S3) allowing the pulse frequency of the RF power supply to be equal to the pulse threshold frequency, starting the pulse RF power supply, realizing sweep frequency matching under an automatic RF sweep frequency function, and switching the pulse frequency of the pulse RF power supply as a preset pulse frequency after matching, (S4) starting the pulse RF power supply, and realizing sweep frequency matching under the automatic RF sweep frequency function. According to the impedance matching method of the pulse RF power supply, the difficulty of realizing impedance matching by the RF power supply can be reduced, thus the matching precision and matching stability of the pulse RF power supply can be improved, and thus the stability of the process is improved.

Sub-nanosecond single ion beam pulses are generated by means of one embodiment of the invention. In this embodiment, an ion source provides ions to a radio frequency quadrupole linear accelerator comprising electrodes. A power source is used to apply radio frequency alternating currents to the electrodes. A device is used to inject ions from the ion source to the accelerator, causing the accelerator to provide only a single sub-nanosecond output beam pulse at a time.

A flexible catheter includes two electrical contacts in a distal region of the catheter and a distal aperture of a hose line. The electrical contacts are connected to a high frequency pulse generator for applying pulsed radio frequency energy for nerve stimulation. A temperature sensor is located in the distal region of the catheter. The flexible catheter is inserted into a region in the spinal canal and the pulsed radio frequency generator is operated, thereby applying pulsed radio frequency energy to a localized region to be treated. The temperature at the distal region of the catheter can also be monitored, and the pulsed radio frequency energy is applied in dependence on the monitored temperature. With the catheter, pain and other medical conditions being related to and influenced by a nervous system are treated.

Methods for treatment of hyperhidrosis, Raynaud's phenomenon, cerebral ischemia and asthma and hypertension by nerve stimulation are disclosed. In particular, the invention relates to the improvement of these conditions by stimulating at least one ganglion selected from the group consisting of T-1 through T-4 ganglia, cervical ganglia, renal nerve or combinations thereof with an implantable, wireless, battery-less and lead-less stimulator. Stimulations of the ganglion may be carried out with pulsed radiofrequency, thermal energy or optical irradiation.

The present invention comprises methods and systems for treating a cardiac arrhythmia in a mammal by administering gated or pulsed radiofrequency current or other ablative energy to the mammal during one or more time periods of increased coronary blood flow. Preferred embodiments of the invention comprise, without limitation, the gated or pulsed administration of radiofrequency current in association with the formation of the dicrotic notch in the arterial blood pressure curve of the mammal. In accordance with the invention, the thermal effects of ablative energy application on the coronary artery are avoided or mitigated due to rapid coronary blood flow resulting in heat loss and minimization of damage to blood vessels.

A method of fabricating a gate of a transistor device on a semiconductor substrate, includes the steps of placing the substrate in a vacuum chamber of a plasma reactor and introducing into the chamber a process gas that includes oxygen while maintaining a vacuum pressure in the chamber. An oxide insulating layer on the order of several Angstroms in thickness is formed at the surface of the substrate by generating a plasma in a plasma generation region within the vacuum chamber during successive “on” times, and allowing ion energy of the plasma to decay during successive “off” intervals separating the successive “on” intervals, the “on” and “off” intervals defining a controllable duty cycle. During formation of the oxide insulating layer, the duty cycle is limited so as to limit formation of ion bombardment-induced defects in the insulating layer, while the vacuum pressure is limited so as to limit formation of contamination-induced defects in the insulating layer. A conductive gate electrode is formed over the insulating layer.