2576 results about "Noise level" patented technology

An electronic compass system includes a magnetic sensor circuit having at least two sensing elements for sensing perpendicular components of the Earth's magnetic field vector. A processing circuit is coupled to the sensor circuit to filter, process, and compute a heading. The processing circuit further selects an approximating geometric pattern, such as a sphere, ellipsoid, ellipse, or circle, determines an error metric of the data points relative to the approximating pattern, adjusts the pattern to minimize the error, thereby obtaining a best fit pattern. The best fit pattern is then used to calculate the heading for each successive sensor reading provided that the noise level is not noisy and until a new best fit pattern is identified. The electronic compass system is particularly well suited for implementation in a vehicle rearview mirror assembly.

A noise reduction circuit for reducing the effects of low frequency noise such as wind noise in communications applications is described. In one embodiment, the noise reduction circuit features a high pass filter formed by exploiting the existing off-chip AC coupling capacitances in making the connection to the source of audio signals. The filter may be adaptive to environmental low frequency noise level through programming the shunt resistances. A low-noise wide dynamic range programmable gain amplifier is also described. Adaptive equalization of the audio signal is also described through the utilization of programmable front-end resistors and a back-end audio equalizer.

An apparatus and method provide non-intrusive in-service testing of audio/video synchronization testing without using traditional audio marker tones. The network includes an A/V synchronous test signal generator which injects video and audio markers into the video and audio non-intrusively and routes the two signals into a switch where they are switched into a channel for encoding and transmission via the ATM network. At the distant end the signal is decoded and routed by a switch into the A/V test generator and measurement set where the markers are detected and the A/V skew calculated, after which the audio and video are routed to the subscriber. The A/V test set signal generator includes a Video Blanking Interval (VBI) test signal generator and a white noise generator, the former injecting a marker into the video signal and the later injecting an audio marker into the audio signal. The video marker is injected into the VBI and broadband, background audio noise to measure the delay between the audio and video components of a broadcast. The marking of the audio is accomplished by gradually injecting white noise into the audio channel until the noise level is 6 dB above the noise floor of the audio receiver. As a precursor A/V sync signal, a small spectrum of the white noise is notched or removed. This signature precludes inadvertent recognition of program audio noise as the audio marker.

Embodiments disclosed herein enable detection and improvement of the quality of the audio signal using a mobile device by determining the loss in the audio signal and enhancing audio by streaming the remainder portion of audio. Embodiments disclosed herein enable an improvement in the sound quality rendered by rendering devices by emitting an test audio signal from the source device, measuring the test audio signal using microphones, detecting variation in the frequency response, loudness and timing characteristics using impulse responses and correcting for them. Embodiments disclosed herein also compensate for the noise in the acoustic space by determining the reverberation and ambient noise levels and their frequency characteristics and changing the digital filters and volumes of the source signal to compensate for the varying noise levels.

A display device having a highly reliable electrostatic capacitive type touch panel which allows finger touch inputting and possesses excellent detection sensitivity is provided. With respect to X electrodes and Y electrodes which are formed on an electrostatic capacitive type touch panel, either one of the X electrodes and the Y electrodes is divided corresponding to a ratio between the number of X electrodes and the number of Y electrodes, and a floating electrode is formed in gaps formed along with the reduction of area of the electrode thus adjusting the area of the electrode. Due to the contraction of the area of the individual electrode, a noise level can be lowered more compared to lowering of a signal level and hence, an S/N ratio can be increased thus enhancing the detection sensitivity. Further, a line is branched on a flexible printed circuit board, intersecting lines are formed on a back surface of the flexible printed circuit board, and the intersecting lines are arranged to orthogonally intersect with lines formed on a front surface of the flexible printed circuit board thus lowering line capacitance.

A digital VSB transmission system in disclosed. The system is compatible with the existing ATSC 8T-VSB receiver and able to transmit additional supplemental data as well as MPEG image/sound data. It initially encodes the information bit of the supplemental data with a ½ encoding rate in order to produce a parity bit and sends the parity bit together with the information bit. Therefore, both of the MPEG image/sound data and the supplemental data can be transmitted properly even through a channel having a high ghost and/or noise level. Particularly, it can significantly improve performances of the slicer predictor and trellis decoder of the VSB receiver.

A dimmable, light-emitting diode (LED) power supply adapted to provide a direct current (DC), constant current (“constant current source”) from a conventional, phase-controlled 120 VAC, 60 Hz power source is disclosed. The constant current source of the present invention utilizes two processes to control dimming. In a first process, the phase angle of the input voltage is used to control the duty cycle of a line frequency pulse width modulation (PWM). In a second process, a proportional-current limit adjustment is used to control the average current to the LED during the ON time of the line frequency by PWM. As a result, at relatively low phase angles, peak currents can be lowered, reducing flicker and improving the audible noise levels generated by the circuit.

In one exemplary embodiment of the invention, a method and computer program include: receiving first and second ciphertexts having first and second data encrypted per an encryption scheme, the encryption scheme has public/secret keys and encryption, decryption, operation and refresh functions, the encryption function encrypts data, the decryption decrypts ciphertext, the operation receives ciphertexts and performs operation(s) on them, the refresh operates to prevent growth of the magnitude of noise for a ciphertext while reducing the modulus of the ciphertext without using the secret key, utilizing a modulus switching technique that involves transforming a first ciphertext c modulo q into a second ciphertext c′ modulo p while preserving correctness, the technique includes scaling by p/q and rounding, p<q; using the operation function(s), performing operation(s) on them to obtain a third ciphertext; and reducing a noise level of the third ciphertext using the refresh function.

A cordless telephone system provides home security. Each handset associated with the cordless telephone system detects a noise level. If the detected noise level exceeds a threshold level, the handset detecting the noise level exceeding the threshold level initiates a telephone call through the base unit to an alert telephone number. When the telephone call to the alert telephone number is established, a message is played to provide notification of a possible home security breach, such as an intruder.

Interfaces for positive pressure therapy having various vent designs are disclosed herein. The interfaces include a bias flow vent with design geometries that help reduce and/or minimize draft and noise levels of the fluids exiting the vents. Some of the vent designs include particular vent hole geometries, plenum spaces, diffusers and fibrous media.

A system, method and wireless earpieces for managing power utilized by a pair of wireless earpieces. Ambient light conditions and noise levels in an environment of the pair of wireless earpieces are determined. The low power settings are activated for the pair of wireless earpieces in response to determining the ambient light conditions are below a light threshold or the noise levels are below a noise threshold; signal activity is below an activity threshold.

Agile frequency converter and method, IF-RF level exchange process, and notch filtering techniques. System noise and spurious levels generated by channel frequency conversion is reduced in applications requiring broadband combining of frequency converters to form multichannel composite signal. Converter employs two-stage frequency conversion process, with gain exchange system using variable pre-mixer gain and variable post-mixer attenuation to maintain constant RF output signal power level. For those few conversion frequencies where distortion component(s) cannot be filtered without degrading desired signal, IF-RF level exchange is optimized for meeting the carrier-to-distortion (C/D) ratio specifications at slight expense of noise level for that channel only, while still meeting aggregate combined carrier-to-noise (C/N) specification requirements. Optimal apportionment of level exchange for each channel depends on specific frequency rejection capability of spurious components and is matched to filtering capability and stored within non-volatile memory of a microcontroller used in the frequency converter.

Disclosed is a method for providing a Global Navigation Satellite System (GNSS) navigation position solution with guaranteed integrity in non-controlled environments, the method including processing a (GNSS) signal including multiple satellites generating at least one signal to obtain carrier phase and pseudorange measurements; pre-processing the measurements to detect and characterize local errors in the measurements, wherein the local errors cannot be ascertained a priori, the characterization including providing error bounds estimated by measuring the carrier phase and pseudoranges measurements, thereby providing a set of measurements rejections when the characterization is not possible; and using the estimated error bounds, together with error bounds provided by the GNSS signal concerning satellite and ionospheric errors, to build in each measurement an estimated noise level in the measurements as input to a weighted Receiver Autonomous Integrity Monitoring (RAIM) algorithm in order to compute position coordinates and associated protection levels in the non-controlled environments.

Monitoring equipment for an elevator drive control includes two modules, a safety circuit sensor system and a motor-switching and/or brake-switching circuit, wherein the monitoring of a safety circuit and the consequential actions resulting therefrom takes place exclusively by means of electronic components while avoiding electrically conductive separating locations. By the use of electronic components, electromechanical switching elements, which have electrically conductive separating locations, can be dispensed with. In addition, an appreciable reduction in the noise level is achieved, since switching noises no longer arise. This has an advantageous effect particularly in the case of elevator installations without a machine room. Furthermore, the manufacturing costs can be significantly reduced and a high security and reliability of the monitoring equipment can be ensured by the use of usual electronic components.

A wireless broadband communications system that can maintain high data rates while taking into account channel interference resulting from operating in shared frequency bands, signal fading resulting from dynamic channel degradation, and signal distortion resulting from compliance with maximum power output regulations. In one mode of operation, the system performs adaptive modulation by transmitting a first signal over a selected channel using a first modulation mode having a level of distortion associated therewith resulting from operating the system at a predetermined maximum power output level. Next, a SINAD level is measured on the first channel. The level of distortion associated with the first modulation mode is then subtracted from the measured SINAD level to obtain a first noise level. In the event the first noise level is less than a noise level required to achieve an acceptable error rate in a next modulation mode, a second signal is transmitted over the selected channel using the next modulation mode.

A method of automatically measuring noise levels of a plurality of uplink paths in a Distributed Antenna System (DAS) includes: sequentially measuring a noise level of each uplink path of the plurality of uplink paths; extracting the noise level of each uplink path at a final end of the uplink path; detecting the noise level of each uplink path; and determining a status of each uplink path by comparing the detected noise level with a threshold value.

A method and system for image quality assessment is disclosed. The image quality assessment method is a no-reference method for objectively assessing the quality of medical images. This method is guided by the human vision model in order to accurately reflect human perception. A region of interest (ROI) of medical image is divided into non-overlapping blocks of equal size. Each of the blocks is categorized as a smooth block, a texture block, or an edge block. A perceptual sharpness measure, which is weighted by local contrast, is calculated for each of the edge blocks. A perceptual noise level measure, which is weighted by background luminance, is calculated for each of the smooth blocks. A sharpness quality index is determined based on the perceptual sharpness measures of all of the edge blocks, and a noise level quality index is determined based on the perceptual noise level measures of all of the smooth blocks. An overall image quality index can be determined by using task specific machine learning of samples of annotated images. The image quality assessment method can be used in applications, such as video/image compression and storage in healthcare and homeland security, and band-width limited wireless communication.