135 results about "Electronic filter" patented technology

PCT No. PCT/DK95/00089 Sec. 371 Date Dec. 27, 1996 Sec. 102(e) Date Dec. 27, 1996 PCT Filed Feb. 27, 1995 PCT Pub. No. WO95/23493 PCT Pub. Date Aug. 31, 1995A method and apparatus for simulating the transmission of sound from sound sources to the ear canals of a listener encompasses novel head-related transfer functions (HTFs), novel methods of measuring and processing HTFs, and novel methods of changing or maintaining the directions of the sound sources as perceived by the listener. The measurement methods enable the measurement and construction of HTFs for which the time domain descriptions are surprisingly short, and for which the differences between listeners are surprisingly small. The novel HTFs can be exploited in any application concerning the simulation of sound transmission, measurement, simulation, or reproduction. The invention is particularly advantageous in the field of binaural synthesis, specifically, the creation, by means of two sound sources, of the perception in the listener of listening to sound generated by a multichannel sound system. It is also particularly useful in the designing of electronic filters used, for example, in virtual reality systems, and in the designing of an "artificial head" having HTFs that approximate the HTFs of the invention as closely as possible in order to make the best possible representation of humans by the artificial head, thereby making artificial head recordings of optimal quality.

The present invention is a method for adjusting different resonant frequencies of a plurality of mechanical resonators formed on a common substrate, in a case where the resonant frequencies of the resonators are a function of each resonator thickness. According to this method the resonators are each formed with an etchable top electrode layer which includes a material having different etching properties as a topmost layer for each of the resonators having different resonant frequencies. By selectively etching these etchable layers one at a time in the presence of the others, one may adjust the resonant frequencies of each of the resonators without need to mask the resonators during the etching process. Associated with this method there is a resonator structure having a top electrode structure having a topmost layer having different etching characteristics for different resonators.

An optical receiver with an electronic filter is described, the parameters of the filter being set by means of high-speed eye monitors. Also described is a high-speed eye monitor with threshold-value decision elements which are set close to the vertices of the eye of an eye diagram, the eye monitor being optimized through connection of a pseudo-error generator and comparison with setpoint values and outputting the eye opening and the Q-factor.

Improved techniques for concurrent channel equalization and far-end crosstalk channel compensation (e.g., estimation and/or cancellation) in a multicarrier data transmission system are disclosed. The improved techniques can produce coefficients for an electronic filter that provide channel equalization and for an electronic filter that provides cancellation of the far-end crosstalk. These coefficients can be initially trained and then subsequently updated during data transmission. Optionally, common coefficient determination resources can be utilized for both far-end crosstalk and near-end crosstalk purposes. These improved techniques are particularly suitable for use with a digital multicarrier communication system having multiple-input multiple-output systems.

A battery powered portable human body carrying electronic human breath filtration device is an electronic nose mask and is the most ideal alternative to conventional filter paper type nose mask. It utilizes electronic ionization technique and electrostatic field to remove air borne particles, dust, pollens, contaminants, bacteria, viruses, toxic chemical, fume and tobacco smoke from human inhalation and exhalation breath. It interacts with human breathing action as the air flow driving system to move the inhalation and exhalation breaths through the electronic filter elements, in addition to a front louver cover and a rear louver cover's protection as pre-filters. The system requires very low running current and uses small batteries usually found in household electronics. This filtration system is light weight with negligible air flow resistance and is integrated into the nose mask which is connected to a pocket size control system via a connection cable.

An electronic filter assembly includes a magnetically conductive annular body extending around a center axis, a set of magnetically conductive prongs radially extending from the center axis toward the annular body, and conductive windings extending around the prongs. The conductive windings can be disposed around the prongs instead of the annular body to assist in conduction of common mode magnetic flux, to reduce impedance of the filter assembly, and/or to more evenly distribute temperature in the filter assembly. A method for forming an electronic filter assembly includes forming an electronic filter assembly having a magnetically conductive annular body extending around a center axis and a set of magnetically conductive prongs radially extending from the center axis toward the annular body. The annular body and the prongs can be formed by coupling plural layers of magnetically conductive bodies together.

Optical impairments such as dispersion and fibre nonlinearity are compensated by generating a pre-distorted electrical signal at the transmitter. This signal is modulated onto a carrier signal, so that it is upconverted in frequency. This up converted signal is then used to modulate an optical source. Generally the optical signal will have two sidebands, one of which has the correctly pre-distorted information and the other which is unwanted. Information in the unwanted optical sideband is either filtered optically or electrically. In the preferred embodiments, the transmitter uses a tunable semiconductor laser with an integrated electroabsorption modulator to modulate the light. The preferred receiver is a coherent receiver with a tunable local oscillator laser. The receiver uses an electrical filter to remove the information in the unwanted sideband.

The invention discloses a single-response microwave photonic filter-based frequency measurement device and a measurement method, and relates to a frequency measurement device and method. The frequency measurement device is provided with a broadband light source, a Mach-Zehnder fiber optic interferometer, an electro-optical modulator, an optical fiber amplifier, a microwave antenna, a dispersion optical fiber, a photo detector and an electrodynamic meter. A tunable single-response microwave photonic filter can be realized by using a structure based on combined Mach-Zehnder fiber optic interferometer spectral division and dispersion optical fiber; the transmission peak frequency position of the single-response microwave photonic filter is adjusted by scanning an adjustable delay line of the optical fiber; and the detection of the frequency of a measured microwave signal is realized by restoring measurement of electric signal power through the photo detector. The microwave electronic filter has an incoherent filter structure; and meanwhile, the detection of a multi-frequency microwave signal is realized through quick length scanning of the adjustable delay line. Remote high-frequency microwave signal frequency measurement of electromagnetic interference can be realized.

A light detector arranged to determine a daylight contribution and an artificial light contribution to a combined illumination level wherein the artificial light comprises individual light coding modulation. The detector comprises:—a photo-sensor arranged to detect the illumination level at its position, and generate an illumination signal; and—a calculator, connected with the photo-sensor for receiving the illumination signal, and arranged to calculate the daylight contribution and the artificial light contribution and output corresponding daylight and artificial light signals. The calculator comprises:—an electronic filter arranged to prepare the illumination signal for estimation of the daylight and artificial light contributions;—a daylight part and an artificial light part, respectively connected to the electronic filter. The artificial light part comprises an artificial light DC component estimator, and the daylight part comprises a total DC component estimator, and a subtractor connected to the total DC component estimator and to the artificial light DC component estimator, and being arranged to determine the daylight contribution as the difference between their outputs. The artificial light DC component estimator is arranged to include present luminaire dimming level data and modulation depth data regarding the light coding modulation in a basis of its estimation.

An electronic filter comprises a housing having input and output ends. The housing has a body and a connector. The connector is located at the input end of the housing. A circuit board is located within the body. A collet assembly is located within the connector to receive electrical signals and conduct them to the circuit board. The collet assembly includes an insulator, a conductor, and an elastomeric sealing member. The insulator is located within the connector. The insulator contains a generally cylindrical opening through its length. The conductor extends through the opening of the insulator. The conductor has an input end adjacent the input end of the housing and an output end adjacent the circuit board. The conductor has a hollow interior at its input end. The sealing member surrounds the insulator in compressed engagement with the insulator and the surrounding connector.

A low let-through voltage surge suppression or protection circuit for protecting hardware or equipment from electrical surges. During operation when no surge condition is present, the circuit allows propagation of signals from a source to a load along a signal path. When a surge is present, the circuit senses and diverts the surge away from the signal path, utilizing common mode and/or differential mode surge protection. An electronic filter is connected in parallel with surge suppression circuit elements for reducing the let through voltage that would otherwise propagate and require a higher power surge suppression circuit element to mitigate. Cascading multiple electronic filters in parallel with surge suppression circuit elements further reduces voltage let through.

The field of the invention is that of surface acoustic wave transponders and associated devices. This invention applies more particularly to the techniques for identifying and locating transponders. It also applies to the transmission of information or measurements, the transponder then being used as a transducer. This type of transponder can, in particular, be used on vehicles, and in particular on road vehicles. The inventive transponder (1) comprises a surface acoustic wave device, comprising one or more electronic filters (101) with narrow spectral band centered on one or more central frequencies and a delay line (102) operating in reflection mode. By having narrowband filters centered on different frequencies, it is thus possible to easily discriminate between different transponders. The delay lines make it possible to simply separate the transmitted signal and the received signal. The inventive transponder can also be used as a transducer. Also, by using an interrogation device that uses two receive antennas, it is possible to locate the position of several transducers with a single interrogation device.

The present invention provides parking curb detection devices and methods for alerting a motor vehicle driver when a predetermined distance from a parking curb has been reached to prevent vehicle damage. An audio and/or a visible signal device alerts the vehicle driver when the correct stopping point has been reached. The present invention utilizes a triangulation led infrared sensor, a control box with digital algorithm filtering, long wave length and bandpass optical filters, and also electronic filters to largely prevent false alerts during bright sunshine conditions.

Printed circuit board capacitors include a first electrode comprising a via extending at least partially through a multi-layer printed circuit board and a plurality of conductive pads in electrical contact with the via and extending radially outward from the via, and a second electrode electrically isolated from the first electrode and comprising a plurality of ground-plane layers of the printed circuit board. The plurality of ground-plane layers include electrically conductive material overlapping the plurality of conductive pads.