4224 results about "Frequency characteristic" patented technology

There is provided an electric device which can prevent a deterioration in a frequency characteristic due to a large electric power external switch connected to an opposite electrode and can prevent a decrease in the number of gradations. The electric device includes a plurality of source signal lines, a plurality of gate signal lines, a plurality of power source supply lines, a plurality of power source control lines, and a plurality of pixels. Each of the plurality of pixels includes a switching TFT, an EL driving TFT, a power source controlling TFT, and an EL element, and the power source controlling TFT controls a potential difference between a cathode and an anode of the EL element.

An active noise cancellation system includes a series of features for more effective cancellation, greater reliability, and improved stability. A particular feature adapted for headset systems includes locating a residual microphone radially offset from the center of a sound generator to detect a signal more similar to that incident upon the eardrum of the user. In addition, an open back headset design includes perforations on the side of the headset instead of the back, so that the perforations are less susceptible to inadvertent blockage. The system also includes a mechanism for detecting changes in the acoustic characteristics of the environment that may be caused, for example, by pressure exerted upon the earpieces, and that may destabilize the cancellation system. The system automatically responds to such changes, for example, by reducing the gain or the frequency response of the system to preserve stability. The system further includes other methods for detecting imminent instability and compensating, such as detecting the onset of signals within enhancement frequencies characteristic of the onset of instability, and adjusting the gain or frequency response of the system or suppressing the enhanced signals. The system further includes a mechanism for conserving battery life by turning the system off when sound levels are low, or adjusting the power supply to the system to correspond to the current power requirements of the system.

A filter network having the capability of establishing multiple, tunable notch frequencies. A notch filter path is established for each notch frequency and includes a bandpass filter and inverter. An input RF signal covering a wide frequency range is applied to all the notch filter paths. Each notch filter path produces an output spectrum that is equal in magnitude and 180.degree. out of phase with respect to an undesired frequency spectrum. A combiner circuit combines the outputs of each notch filter path in parallel with the RF input signal to produce an RF output signal with all desired spectra unchanged and all undesired spectra attenuated.

The loudspeaker device according to the present invention comprises a loudspeaker; a feedforward processing section for performing feedforward processing on an electric signal to be inputted to the loudspeaker based on a preset filter coefficient so that non-linear distortion which occurs from the loudspeaker is removed; and a feedback processing section for detecting vibration of the loudspeaker, and performing feedback processing on an electric signal concerning the vibration with respect to the electric signal to be inputted to the loudspeaker. The feedback processing section performs feedback processing on the electric signal concerning the vibration so that the non-linear distortion which occurs from the loudspeaker is removed and so that a frequency characteristic concerning the vibration of the loudspeaker becomes a predetermined frequency characteristic.

A speaker system for a musical instrument that detects the displacement of a voice coil of a speaker and provides feedback processing. The speaker system has a preamp that alters the frequency characteristics of the an electrical signal that has been input to an input terminal, and a power amplifier that amplifies the electrical signal. A speaker is driven by the power amplifier and a feedback unit detects the displacement of the speaker and provides a feedback signal to the power amplifier. The power amplifier amplifies the electrical signal in conformance with the output of the preamp and the feedback signal.

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.

The invention discloses a pump potential cavitation fault detecting method based on quick spectrum kurtosis analysis. The pump potential cavitation fault detecting method comprises the steps that 1, vibration acceleration signals are collected to be subject to noise reduction to serve as to-be-processed signals; 2, according to the data size of the signals, the resolving order of signal processingis determined; 3, according to the quick spectrum kurtosis algorithm computation result, the optimal carrier frequency and bandwidth are selected; 4, the selected signals within the carrier frequencyand bandwidth are subject to Fourier transformation, and a frequency spectrum envelope diagram is obtained; and 5, an original signal time domain figure, a signal time domain figure treated through quick spectrum kurtosis filtering processing and the frequency spectrum envelope diagram obtained after selected zone Fourier transformation are compared, and cavitation trouble signal time and frequency characteristics are analyzed. By means of the method, more cavitation instant signals can be detected, information in the aspects of time domain and frequency domain is seen more clearly, and the normal state and the cavitation state of a pump can be distinguished obviously.

A computerized model provides a display of a physical environment in which a communications network is or will be installed. The communications network is comprised of several components, each of which are selected by the design engineer and which are represented in the display. Errors in the selection of certain selected components for the communications network are identified by their attributes or frequency characteristics as well as by their interconnection compatability for a particular design. The effects of changes in frequency on component performance are modeled and the results are displayed to the design engineer. A bill of materials is automatically checked for faults and generated for the design system and provided to the design engineer. For ease of design, the design engineer can cluster several different preferred components into component kits, and then select these component kits for use in the design or deployment process.

Wireless communication networks utilize various communication protocols to exchange data between wireless network devices. Overlapping communication frequencies between data exchange protocols present a collision and interference problem when data transmissions are transmitted using similar timing and frequency characteristics during wireless transit. A device and various network configurations for monitoring, moderating, and/or coordinating wireless transmission traffic in a wireless communication network where overlapping communication frequencies coexist is described to significantly reduce or avoid interference caused by signal collisions.

A variety of methods and arrangements for controlling the operation of an internal combustion engine in a skip fire variable displacement mode are described. In general, a firing control unit determines working chamber firings during operation of the engine that are suitable for delivering a desired engine output. In one aspect, the firing control unit is arranged to isolate the generation of firing sequences having frequency components in a frequency range of concern and to alter the firing sequence in a manner that reduces the occurrence of frequency components in the frequency range of concern. In another aspect, a filter is arranged to filter a feedback signal to provide a filtered feedback signal that is used in the determination of the working chamber firings. In preferred embodiments, the frequency characteristics of the filter are variable. In various embodiments, the frequency characteristics of the filter vary as a function engine speed and/or a transmission gear ratio.

An apparatus performs adaptive analog-to-digital conversion. The apparatus according to one embodiment comprises a frequency modulator unit for changing an input analog signal into a modulated analog signal with a frequency spectrum in a bandwidth of interest, a parallel delta sigma conversion unit operatively connected to the frequency modulator unit, the parallel delta sigma conversion unit converting the modulated analog signal into a digital signal, and a controller operatively connected to the frequency modulator unit and the parallel delta sigma conversion unit, the controller adjusting at least one parameter relating to a frequency characteristic of the frequency modulator unit and/or the parallel delta sigma conversion unit.

An inband signaling modem communicates digital data over a voice channel of a wireless telecommunications network. An input receives digital data. An encoder converts the digital data into audio tones that synthesize frequency characteristics of human speech. The digital data is also encoded to prevent voice encoding circuitry in the telecommunications network from corrupting the synthesized audio tones representing the digital data. An output then outputs the synthesized audio tones to a voice channel of a digital wireless telecommunications network.

In one form of the present invention, there is provided a fiber optic communication system comprising: an optical signal source adapted to receive a base binary signal and produce a first signal, said first signal being frequency modulated; and an optical spectrum reshaper adapted to reshape the first signal into a second signal, said second signal being amplitude modulated and frequency modulated; characterized in that: the frequency characteristics of said first signal, and the optical characteristics of said optical spectrum reshaper, being such that the frequency characteristics of said second signal are configured so as to increase the tolerance of the second signal to dispersion in a transmission fiber. In another form of the present invention, there is provided an optical transmitter comprising: a frequency modulated source for generating a first frequency modulated signal, and an amplitude modulator for receiving the first frequency modulated signal and for generating a second amplitude and frequency modulated signal. In another form of the present invention, there is provided a method for transmitting an optical signal through a transmission fiber comprising: receiving a base binary signal; operating an optical signal source using the base binary signal to produce a first signal, said first signal being frequency modulated; passing the frequency modulated signal through an optical spectrum reshaper so as to reshape the first signal into a second signal, said second signal being amplitude modulated and frequency modulated; the frequency characteristics of said first signal, and the optical characteristics of said optical spectrum reshaper, being such that the frequency characteristics of said second signal are configured so as to increase the tolerance of the second signal to dispersion in a transmission fiber; and passing the second signal through a transmission fiber. In another form of the present invention, there is provided a method for transmitting a base signal, comprising: using the base signal to produce a frequency modulated signal; and providing an amplitude modulator for receiving the frequency modulated signal and for generating an amplitude and frequency modulated signal.

Methods and systems for vector combining power amplification are disclosed herein. In one embodiment, a plurality of signals are individually amplified, then summed to form a desired time-varying complex envelope signal. Phase and/or frequency characteristics of one or more of the signals are controlled to provide the desired phase, frequency, and/or amplitude characteristics of the desired time-varying complex envelope signal. In another embodiment, a time-varying complex envelope signal is decomposed into a plurality of constant envelope constituent signals. The constituent signals are amplified equally or substantially equally, and then summed to construct an amplified version of the original time-varying envelope signal. Embodiments also perform frequency up-conversion.