311 results about "Electromagnetic transmission" patented technology

An electromagnetic transmission and reception system comprises a transmitter section and a receiver section. The transmitter section has a first signal source, a second signal source at a lower frequency than the first signal source, and means for generating from the first and second signal sources a plurality of signals with fixed frequency spacing derived from the second signal source frequency. One or more pairs of the plurality of signals are selected, and for the or each pair, the signals of the pair are combined to derive an output signal having a frequency derived from the difference between the frequencies of the signals of the pair. The receiver section combines a received signal, which comprises a received version of the output signal, with a local oscillator signal for frequency down-conversion of the received signal. This local oscillator signal is generated by the transmitter section. This provides a system in which the generation of signals of the desired frequency is achieved by mixing signals of specific frequencies. The reception uses frequency down-conversion using the same signal sources as used for the transmission. This enables a low noise system to be implemented.

The invention provides for electromagnetic transmission and reception used in detecting relative changes associated with nano devices existing within an oil reservoir. The system enables monitoring of the relative movement of the nano devices in the oil and/or water over a given area based on the incremental or relative changes of the intensity of the reflections over time. In one embodiment, a source of electromagnetic energy from an array of antennae transmitting immediately in the far field recharges a power source embedded in the nano devices. In another embodiment, the return signals from the nano devices maps the morphology of ensembles of nano devices. In yet another embodiment the transmission controls the movement of the nano devices and controls the function preformed by the nano devices relative to effecting changes in the well to improve production of oil.

A method of responding to an anomalous change in downhole pressure in a bore hole comprises detecting the anomalous change in downhole pressure, sending a signal along the segmented electromagnetic transmission path, receiving the signal, and performing a automated response. The anomalous change in downhole pressure is detected at a first location along a segmented electromagnetic transmission path, and the segmented electromagnetic transmission path is integrated into the tool string. The signal is received by at least one receiver in communication with the segmented electromagnetic transmission path. The automated response is performed along the tool string. Disclosed is an apparatus for responding to an anomalous change in downhole pressure in a downhole tool string, comprising a segmented electromagnetic transmission path connecting one or more receivers and at least one pressure sensor.

Methods and systems are provided for processing secure transactions. An electromagnetic transmission packet is received from a portable device at a processing device. The electromagnetic transmission packet includes an encrypted magnetic-stripe image and an encrypted version of an alphanumerical identifier. A keyed nonencrypted version of the alphanumerical identifier is received at the processing device, and the encrypted version of the alphanumerical identifier is decrypted. The decryption of the encrypted version of the alphanumerical identifier is compared with the nonencrypted version of the alphanumerical identifier. Thereafter, a decryption of the encrypted magnetic-stripe image is transmitted to a host system for processing the secure transaction using an account identified by the decryption of the magnetic-stripe image.

Exemplary systems and methods are directed to transmission of electromagnetic (EM) pulses in a downhole environment, which is located below a surface of a landform. A sequence of EM energy pulses is generated from a signal generator located at the surface of the landform. The energy pulses are reflected at a ring frequency by one or more downhole transducers. The reflected energy pulse is received at a receiver, which is located at the surface, during a predetermined time interval. The receiver detects the received energy pulses through a time domain or frequency domain technique. The detected ring frequency is correlated to a parameter or condition of the downhole environment.

The invention relates to a refrigerating appliance, especially a refrigerator, comprising a plate which consists of photoconductive material which can be removed from the refrigerating appliance with an electric light source which comprises a first electrical or electromagnetic transmission element which interacts—in the inserted or mounted state of the plate—with a second electrical or electromagnetic transmission element applied to the refrigerating appliance, in such a way that electrical current can be transmitted from the second electrical or electromagnetic transmission element.

A partially implantable vestibular prosthesis system is described which includes an external movement sensor that is attachable to the outer skin surface of a patient's head for generating an external movement signal which represents movement of the patient's head. An external transmitter is in communication with the external movement sensor and provides an electromagnetic transmission of an implant communication signal which includes a signal component based on the external movement signal and an electrical power component that provides electrical power for implanted system components. An internal movement sensor is implantable under the skin of the patient's head for generating an internal movement signal which represents movement of the patient's head. And an implant processor also is implantable under the skin and in communication with the internal movement sensor and the external transmitter for generating an implant stimulation signal based on one of the movement signals to electrically stimulate target neural tissue for vestibular sensation by the patient.

The invention discloses a fast electromagnetic compatibility test and diagnosis system with quantization electromagnetic interference. A receiving antenna of the system is arranged on a frequency spectrum tester, a chuck end of a current probe is clamped on a cable through which tested objects are connected, the other end of the current probe is connected on the frequency spectrum tester which is connected with a computer; and the computer is internally provided with a fast electromagnetic compatibility test and diagnosis unit. The fast electromagnetic compatibility test and diagnosis unit is used for fast testing the electromagnetic-transmitted frequency spectrum of the tested objected on site, conducting analysis and diagnosis to the electromagnetic-transmitted frequency spectrum, and judging whether the electromagnetic transmission characteristic exceeds a standard limit value or has abnormality. The fast electromagnetic compatibility test and diagnosis system has important meaning on solving the electromagnetic compatibility problem and monitoring and evaluating the electromagnetic environment.

The utility model discloses a tunable-frequency Terahertz metamaterials modulator comprising unit devices arranged periodically. Each unit device comprises a substrate, a functional material layer and metal resonator units. The functional material layer is arranged on the substrate, and the metal resonator units are arranged on the functional material layer. When the functional material layer turns to a metal phase from an insulation phase, conductivity of the functional material layer is exponentially increased to increase areas of middle open capacitance of the metal resonator units, the resonator frequency of the metal resonator units is decreased with the increase of the capacitance, so that frequency tuning of the unit devices is realized. By the aid of the tunable-frequency Terahertz metamaterials modulator, the metal opening resonator units arranged periodically are produced on the substrate in the Terahertz wave band of low transmitting consumption, conductivity changes before and after phase changes of the metal insulation phase change materials are used to change areas of the open capacitance of the resonator units, and resonant frequency is tunable; and initiative control of electromagnetic transmission features at a particular frequency by the Terahertz wave band is realized, and large switch ratio or high-modulation depth genera is obtained.

The invention discloses a method for testing the shielding effectiveness of an electromagnetic shielding material in the technical field of electromagnetic shielding. The method comprises the following steps that a reference sample with known electromagnetic parameters and different electromagnetic frequencies are selected, and the electromagnetic transmission intensity of an electromagnetic transmitter is set; a testing window is sealed by the reference sample, and the electric field intensity received by electromagnetic receivers which correspond to different electromagnetic frequencies is measured; the testing window is tested by a material to be tested, and the electric field intensity received by the electromagnetic receivers which correspond to different electromagnetic frequencies is measured; and the shielding effectiveness of materials to be tested corresponding to different frequencies relative to the reference sample is calculated and the conductivity of the materials to be tested is estimated. The testing method is not affected by the size of a shielding room (box), the size of the window, the resonance of the shielding room and other factors, and overcomes the defect that the testing results of a traditional shielding room method are not portable among different configuration.

The invention relates to the field of metamaterial devices and provides a switching-controllable THz wave metamaterial perfect absorber (MPA) and a control method thereof. The switching-controllable THz wave metamaterial perfect absorber comprises a substrate, an MIT (metal-insulator transition) layer positioned on the substrate, a dielectric layer positioned on the MIT phase change layer and metal opening resonance units positioned on the dielectric layer and being in cyclic arrangement, and the on/off of the absorber at the resonance frequencies of the metal opening resonance units is realized through changing the conductivity of the MIT phase change layer. According to the invention, the variation of the conductivities of the MIT phase-change material before and after phase change is utilized to change the absorptivity of the absorber, so that the THz MPA can be turned on/off near the resonance frequency of the metal opening resonance units, initiative control of the electromagnetic transfer characteristics of THz wave bands at the specific frequency, and accordingly, a larger on-off ratio or modulation depth can be obtained; and the switching-controllable MPA adopting the substrate-vanadium dioxide-dielectric layer-SRRs (Split Ring Resonators) four-layer structure can control the conductivity of vanadium dioxide through an external field so as to control the absorptivity of the MPA.

A combination of filters for filtering selected wavelengths of electromagnetic radiation is provided on a transparent substrate such as a plastic film or glazing of a window. The combination of filters prevents or attenuates the passage of wavelengths through the substrate into a building, where the passage of the wavelengths into the building could adversely affect people or machinery within the building. The combination of filters is useful improve wireless networks performance by blocking or attenuating undesired electromagnetic interference, and radio frequency interference.

A method of fabrication and device made by preparing a photosensitive glass substrate comprising at least silica, lithium oxide, aluminum oxide, and cerium oxide, masking a design layout comprising one or more holes to form one or more electrical conduction paths on the photosensitive glass substrate, exposing at least one portion of the photosensitive glass substrate to an activating energy source, exposing the photosensitive glass substrate to a heating phase of at least ten minutes above its glass transition temperature, cooling the photosensitive glass substrate to transform at least part of the exposed glass to a crystalline material to form a glass-crystalline substrate and etching the glass-crystalline substrate with an etchant solution to form one or more angled channels that are then coated.

The invention provides a signal wireless electromagnetism transmission system while drilling. The signal wireless electromagnetism transmission system while drilling comprises a drill pipe, a drill collar, a drill tool, an electromagnetic signal emission module, a relay pup joint module and an electromagnetic receiving module. The electromagnetic signal receiving module comprises a loop metal tube, a loop antenna and a receiving circuit, the loop antenna and the receiving circuit are arranged in a loop groove at the bottom of the outer side of the loop metal tube, and the loop metal tube is sleeved on the ground drill pipe. The electromagnetic signal emission module is arranged in a loop groove of the outer side of the drill collar, and the drill collar is connected between the drill tool and the drill pipe. The relay pup joint module comprises a metal drill pipe pup joint, two groups of loop antennas, a relay amplifying circuit and battery, and the metal drill pipe pup joint is connected between the upper section of the drill pipe and the lower section of the drill pipe. The two groups of loop antennas, the relay amplifying circuit and the battery are arranged in a loop groove of the outer side of the metal drill pipe pup joint. By the way of relay, relaying transmission is carried out, transmission distance is not limited, and the data transmission rate is higher.

A system of contactless electromagnetic transmission between a terminal including a series oscillating circuit for generating an electromagnetic field and a transponder including a parallel oscillating circuit, these oscillating circuits being sized so that the coupling coefficient between them rapidly decreases when the distance separating the transponder from the terminal becomes smaller than a predetermined value.

Disclosed is an electromagnetic wave transmission device with regulative and controllable magnetic field based on sub-monolayer wavelength metal grating; the device comprises a sub-monolayer wavelength metal grating and magnetoactive medium filled in the slit of the sub-monolayer metal grating; the metal part of the device and the magnetoactive medium have the same thickness, the thickness at least meets and supports the lowest-level Fabry-Perot cavity resonance demand of the designed work wavelength in the grating slit; the period and slit of the grating are shorter than the wavelength of the electromagnetic wave. By changing the size of the additional magnetic field, the propagation constant of the waveguide mode in the metal grating slit can be regulated to change the electromagnetic transmission characteristic of the device and realize the purpose of initial regulation of polarization-independent electromagnetic wave transmission spectrum and the electromagnetic wave transmission spectrum magnetic field.

An enhanced wireless network system including a visible-light transparent, transmission shielding component for application to or incorporation in windows to create a shielded wireless network operation area. The shielding component enhances network performance by substantially reducing extraneous electromagnetic interference and enhances network security by substantially containing electromagnetic transmissions to desired areas. The shielding component may comprise several alternating layers of metal, to substantially attenuate transmissions to varying degrees, including attenuation of 20 to 50 db in the 1 MHz to 100 GHz range and beyond, while simultaneously permitting substantial transmission of visible light (such as 15-55%).

The invention relates to a converter circuit (50) for transferring electrical energy, in particular for application in a motor vehicle wiring system (38, 42), which converter circuit comprises an electromagnetic transfer unit (60) having three electromagnetic transfer members (62, 64, 66) that can be electromagnetically coupled to each other in order to transfer electromagnetic energy, wherein the first electromagnetic transfer member (62) is connected to a first bi-directional converter circuit that comprises a first voltage connection pole pair (80) for connecting an AC voltage source and/or sink (54), wherein the second electromagnetic transfer member (64) is connected to a rectifier converter circuit that is connected on the outlet side to an electrical energy store (88), and wherein the third electromagnetic transfer member (66) is connected to a second bi-directional converter circuit that comprises a second voltage pole pair (96) for connecting a DC voltage source and/or sink (98), and a control unit (100) that is connected to the first bi-directional converter circuit, the second bi-directional converter circuit and the rectifier converter circuit, in order to control the exchange of electrical energy between the AC voltage source and/or sink (54), the DC voltage source and/or sink (98) and/or the electrical energy store (88).

A system of contactless electromagnetic transmission between a terminal including a series oscillating circuit for generating an electromagnetic field and a transponder including a parallel oscillating circuit, these oscillating circuits being sized so that the coupling coefficient between them strongly decreases when the distance separating the transponder from the terminal becomes greater than a predetermined value.