1029 results about "Signal synthesis" patented technology

An auditory scene is synthesized from a mono audio signal by modifying, for each critical band, an auditory scene parameter (e.g., an inter-aural level difference (ILD) and / or an inter-aural time difference (ITD)) for each sub-band within the critical band, where the modification is based on an average estimated coherence for the critical band. The coherence-based modification produces auditory scenes having objects whose widths more accurately match the widths of the objects in the original input auditory scene.

A system and method are disclosed for extending the bandwidth of a narrowband signal such as a speech signal. The method applies a parametric approach to bandwidth extension but does not require training. The parametric representation relates to a discrete acoustic tube model (DATM). The method comprises computing narrowband linear predictive coefficients (LPCs) from a received narrowband speech signal, computing narrowband partial correlation coefficients (parcors) using recursion, computing Mnb area coefficients from the partial correlation coefficient, and extracting Mwb area coefficients using interpolation. Wideband parcors are computed from the Mwb area coefficients and wideband LPCs are computed from the wideband parcors. The method further comprises synthesizing a wideband signal using the wideband LPCs and a wideband excitation signal, highpass filtering the synthesized wideband signal to produce a highband signal, and combining the highband signal with the original narrowband signal to generate a wideband signal. In a preferred variation of the invention, the Mnb area coefficients are converted to log-area coefficients for the purpose of extracting, through shifted-interpolation, Mwb log-area coefficients. The Mwb log-area coefficients are then converted to Mwb area coefficients before generating the wideband parcors.

A transmission apparatus used in a radio communication system adopting the OFDM scheme is disclosed. The transmission apparatus includes: a dividing inverse Fourier transform part including plural transform parts, wherein the dividing inverse Fourier transform part divides a signal to be transmitted into plural signals, and each of the plural transform parts performs inverse Fourier transform on one of the plural signals; a peak control part for outputting a peak control signal based on peaks that are detected from output signals of the dividing inverse Fourier transform part; and a peak reducing process part for adjusting a weight or an arranging order of an output signal of the dividing inverse Fourier transform part according to the peak control signal to output an adjusted signal, and synthesizing the adjusted signal with other signal so as to output a synthesized signal.

The invention provides audio bandwidth expansion coding and decoding devices which can reconstruct a high frequency signal by using the lower code rate so as to improve the quality of the output audio signal. The audio bandwidth expansion coding device comprises a frequency division module, a core coder module, a linear prediction analysis module, a spectrum envelope quantization module, a high and low frequency correlation computation module and a gain computation module; and the audio bandwidth expansion decoding device comprises a core decoder module, a high-frequency spectrum envelope reconstruction module, a high-frequency residual error reconstruction module, a high-frequency gain adjustment module, a high-frequency signal synthesis module and a wideband signal reconstruction module.

A method and apparatus are disclosed for enhancing, within a signal bandwidth, a corrupted audio-frequency signal. The signal which is to be enhanced is analyzed into plural sub-band signals, each occupying a frequency sub-band smaller than the signal bandwidth. A respective signal gain function is applied to each sub-band signal, and the respective sub-band signals are then synthesized into an enhanced signal of the signal bandwidth. The signal gain function is derived, in part, by measuring speech energy and noise energy, and from these determining a relative amount of speech energy, within the corresponding sub-band. In certain embodiments of the invention, the signal gain function is also derived, in part, by determining a relative amount of speech energy within a frequency range greater than, but centered on, the corresponding sub-band. In other embodiments of the invention, the sub-band noise energy is determined from a noise estimate that is updated at periodic intervals, but is not updated if the newest sample of the signal to be enhanced exceeds the current noise estimate by a multiplicative threshold (i.e., a threshold expressible in decibels). In still other embodiments of the invention, the value of the noise estimate is limited by an upper bound that is matched to the dynamic range of the signal to be enhanced.

There is provided a radio-frequency communication device that can sufficiently eliminate a leakage signal from a transmission side included in a received signal. The communication device includes a cancel amplitude controlling unit 62 selectively suppressing supply of a cancel signal to a cancel signal synthesizing unit 52, a received-signal terminating unit 50 selectively terminating a received-signal input terminal 64i, a signal strength detecting unit 78 detecting a signal strength, a memory unit 82 storing a signal strength detected by the signal strength detecting unit 78, a signal strength comparing unit 80 comparing a plurality kinds of signal strengths read out from the memory unit 82, and a cancel signal controlling unit 72 controlling an amplitude and / or a phase of the cancel signal based on a result of the comparison by the signal strength comparing unit 80. Thus, suppressing the cancel signal by the cancel amplitude controlling unit 62 enables accurate detection of a strength of the received signal, as well as terminating the received signal by the received-signal terminating unit 50 enables accurate detection of a strength of the cancel signal.

The invention provides an audio signal switching method and an audio signal switching device. The audio signal switching method comprises the following steps of: when an audio signal switches, performing weighted processing on a first high-frequency band signal of the audio signal of a current frame and second high-frequency band signals of the audio signals of first M frames so as to obtain a processed first high-frequency band signal, wherein M is greater than or equal to 1; and synthesizing the processed first high-frequency band signal and a first low-frequency band signal of the audio signal of the current frame into a broad band signal. By processing the first high-frequency band signal of the current frame according to the second high-frequency band signals of the audio signals of the first M frames, the second high-frequency band signals of the audio signals of the first M frames can transit to the processed first high-frequency band signal smoothly, so that the audio signals with different band widths can be switched smoothly and the quality of the audio signals received by a user is improved.

Systems and methods are described for HF radar frequency sharing with GPS time modulation multiplexing. A method is provided that includes generating clock signals from the time information contained in a GPS signal. Radio frequency signals are transmitted and received in a sequence whose start times are dictated by the clock signals. The clock signals also control the modulation of the radio frequency signals. The radio frequency signals are modulated by using a sweep modulation. An apparatus to implement the method includes a GPS receiver, a state machine, a clock generator, a microprocessor, a memory chip, a signal synthesizer, and a digital data output device. The GPS receiver extracts time information from GPS signals. The state machine controls radar functions versus time. The microprocessor performs modulation multiplexing on radar signals.

A signal processing apparatus includes a decoding unit, an analyzing unit, a synthesizing unit, and a selecting unit. The decoding unit decodes an input encoded audio signal and outputs a playback audio signal. When loss of the encoded audio signal occurs, the analyzing unit analyzes the playback audio signal output before the loss occurs and generates a linear predictive residual signal. The synthesizing unit synthesizes a synthesized audio signal on the basis of the linear predictive residual signal. The selecting unit selects one of the synthesized audio signal and the playback audio signal and outputs the selected audio signal as a continuous output audio signal.

An audio signal encoding device is provided comprising an input for receiving a sub-frame of an audio signal, a voiced audio signal synthesis stage, an unvoiced audio signal synthesis stage, and a processing unit. The voiced audio signal synthesis stage is operative for producing a first synthetic audio signal approximating the sub-frame of an audio signal received at the input on the basis of a first set of parameters. The unvoiced audio signal synthesis stage is operative for producing a second synthetic audio signal approximating the sub-frame of an audio signal received at the input on the basis of a second set of parameters. The processing unit is operative for releasing a set of parameters allowing to generate a selected one of the first synthetic audio signal and the second synthetic audio signal.

This invention relates to a system (100) and method for synthesizing an audio input signal of a hearing device. The system (100) comprises a microphone unit (102) for converting the audio input signal to an electric signal, a filter unit (110) for removing a selected frequency band of the electric signal and pass a filtered signal, a synthesizer unit (118) for synthesizing the selected frequency band of the electric signal based on the filtered signal thereby generating a synthesized signal, a combiner unit (120) for combining the filtered signal and the synthesized signal so as to generate a combined signal, and finally an output unit (122, 124, 126) for converting the combined signal to an audio output signal.

The invention relates to an auto-stability method for camera image and the auxiliary device used in hand held state or motion state. It uses angular velocity sensor to check the angular velocity of the camera rotating round the three space axes in real-time and records synchronistical with image signal. The variance of the attitude angle between two pictures would be gained by integral in afterward process software, and the attitude angle variance related to slow-varying low frequency element in motion angular velocity is reserved, meanwhile the attitude angle variance related to dithering angle element would be eliminated. Then, the image dithering would be eliminated by translation and rotation the image. The device is made up of three same circuits. And every process circuit is connected by angular velocity checking circuit which is belonged to signal collection circuit, power lever shifting circuit which is belonged to signal process circuit, voltage / frequency transformation circuit, frequency division circuit, wave transformation circuit, signal compound and extent regulation circuit in series. The output signal is sent to the interface of camera.

A signal transmission apparatus for transmitting a signal using multiple antenna elements comprises a transmission signal generator configured to convert at least one of a first signal addressed to an arbitrary mobile terminal belonging to a geographical area and a second signal addressed to a specific mobile terminal located in a part of the geographical area into one or more transmission signals to be transmitted using a prescribed beam pattern; a weighting adjustor configured to weight said one or more transmission signals for each of the antenna elements to define the prescribed beam pattern; and a signal synthesizer provided for each of the antenna elements and configured to synthesize the weighted transmission signals.

A short-time exposure image data and a long-time exposure image data of the same object to be photographed are stored to SE memory and LE memory and then transferred to CPU, motion thereof being detected at a motion detecting section on the basis of the two image data; if no motion is detected, a wide dynamic range, synthesized image as synthesized at a synthesizing circuit on the basis of image data read out from the two memories and compressed is outputted through a selector controlled by CPU. If a motion is detected, the long-time exposure image data read out from the LE memory and processed at a signal processing circuit is outputted through the selector. An image pickup apparatus having a function for generating wide dynamic range, synthesized image by synthesizing image signals corresponding to a plurality of frames of different exposure amounts is thereby able to perform ON / OFF switching of the generating function of synthesized image on the basis of previously taken image data, so that a failed synthesized image can be prevented from being outputted.

Systems and methods are described for HF radar frequency sharing with GPS time modulation multiplexing. A method is provided that includes generating clock signals from the time information contained in a GPS signal. Radio frequency signals are transmitted and received in a sequence whose start times are dictated by the clock signals. The clock signals also control the modulation of the radio frequency signals. The radio frequency signals are modulated by using a sweep modulation. An apparatus to implement the method includes a GPS receiver, a state machine, a clock generator, a microprocessor, a memory chip, a signal synthesizer, and a digital data output device. The GPS receiver extracts time information from GPS signals. The state machine controls radar functions versus time. The microprocessor performs modulation multiplexing on radar signals.

Provided is a complex exponential modulation filter bank which can reduce quantity of arithmetic operation, and can realize low electric power consumption or speeding-up. This complex exponential modulation filter bank has a step of calculating a first intermediate signal from an input signal, a step of calculating a second intermediate signal from the first intermediate signal, a step of calculating a third intermediate signal from the second intermediate signal with fast Fourier transform, and a step of calculating a complex band output signal from the third intermediate signal.

A method of adaptive full duplex full frequency band echo cancellation comprises the following steps of: carrying out filtration by a sub-band filter, carrying out sub-band echo cancellation by a sub-band echo canceller, carrying out weighted energy analysis and control on system signals, carrying out analysis and detection on double talk active state, carrying out coefficient updating on an echo filter, carrying out nonlinear processing on residual echo, and carrying out synthesis on signals of sub-bands. The method further comprises the step of maintaining reference signal and echo signal to be synchronous; after the nonlinear processing is carried out, noise reduction, automatic gain control and comfort noise technique can be added. Owing to adoption of the method of echo cancellation, signals are spilt into sub-bands through filtration, thus reducing correlation among signals of sub-bands, improving convergence problem of adaptive filter, reducing data process load of the system, improving processing efficiency of echo cancellation, realizing full duplex of conversation, improving frequency response of communication audio frequency, improving quality of communication and realizing echo cancellation of full frequency band response.

A multi-channel signal processing system includes a filter unit arranged at a signal transmitting end and a feedback unit arranged at a signal receiving end. The filter unit includes a signal synthesis unit and a filter, where the filter is adapted to filter crosstalk source signals of signals to be transmitted and perform subsequent filtering in accordance with received feedback information; the signal synthesis unit is adapted to receive the signals to be transmitted which are input and the crosstalk source signals filtered by the filter, and synthesize the signals to be transmitted and the crosstalk source signals; and the feedback unit is adapted to make a feedback to the filter in accordance with the received signals to be transmitted.

A Hall sensing circuit generates a positional detection signal representative of a positional relationship between a rotor and a phase coil of a motor. A signal synthesizing circuit transforms the positional detection signal to a driving signal. Based on a comparison of the driving signal and a high-frequency reference signal, a pulse signal is generated for controlling a switching circuit to dive the motor. A current error signal is supplied through feedback to adjust a relative relationship between an amplitude of the drive signal and an amplitude of the high-frequency reference signal, thereby changing a duty ratio of the pulse signal. A duty-ratio limiting circuit is provided to limit the duty ratio of the pulse signal for ensuring a reliable rotation of the motor.

A method of measuring the contents of a search volume. The method includes: energising one or more transmitters so as to transmit electromagnetic wave energy into the search volume; detecting the effect of the search volume on the passage of the electromagnetic wave energy by recording two or more signals, each signal being associated with a different propagation path (typically either a monostatic or bistatic path) within the search volume; aligning the signals in order to generate two or more aligned signals which are synthetically focused on a desired voxel in the search volume, each aligned signal being associated with a different propagation path (typically either a monostatic or bistatic path) within the search volume; calculating a quality factor by processing the aligned signals to generate two or more data values, and processing the data values to generate a quality factor, the quality factor being indicative of a degree of coherence in the aligned signals; summing the aligned signals to generate a summed signal; and processing the summed signal to generate an output which is indicative of the internal structure of the search volume at the location of the desired voxel, the output varying in accordance with the quality factor.

Provided are an apparatus and method for visualizing multichannel audio signals. The apparatus includes a spatial audio decoding unit for receiving a downmix signal of a time domain, converting the downmix signal into a signal of a frequency domain to output a frequency domain downmix signal, and synthesizing a multichannel audio signal based on the spatial parameter and the downmix signal; and a multichannel visualizing unit for creating visualization information of the multichannel audio signal based on the frequency domain downmix signal and the spatial parameter.

The invention discloses a new balance detection bias control method for an MZ external modulator. The method comprises the following steps: sending RF (radio frequency) signals and pilot signals into a signal end of the MZ external modulator after synthesizing the RF signals and the pilot signals by a signal synthesizer, wherein modulated light signals pass through an optical splitter and part of the optical signals enter an photoelectric detector; converting the part of the optical signals into electric signals by the photoelectric detector; detecting the electric signals; detecting fundamental waves and secondary harmonics of the pilot signals or two or more harmonic components; performing division operation on a transmission function of the two harmonic components and obtaining an adjustment amount of a direct current bias according to a ratio function after the division operation; and obtaining a bias voltage according to the adjustment amount of the direct current bias and sending the bias voltage into the direct current bias end of the MZ external modulator to realize the closed-loop control of an optimal direct current bias point of the MZ external modulator. By using the method, the influence on the precision of a direct current bias control method caused by the output power of a laser and the loss of a link can be eliminated, so that the precision of a system is improved.

A signal testing system is disclosed, which is capable of achieving a bi-directional wireless transmission measurement enabling mutual testing between device-under-tests and reference devices by configuring a symmetrical structure with circulators and multiplexers. Moreover, the signal testing system not only is capable of fetching signal out of a test path by the use of power dividers and then transmitting the fetched signal to a signal analyzer to be analyzed so as to enable the system to support multiple testing, but also is capable of generating a signal used for referencing by a signal synthesizer so as to enable the system to support numerous tests. In addition, both the signal analyzer and the signal synthesizer have a switch control integrated therein, which enables the signal analyzer to perform analysis on signals of different frequency bandwidth, and enables the signal synthesizer to generate signals of different frequency bandwidth as require.

Adjust equipment and method for array antenna transmitting link, include: power detect device, signal synthesize device and array adjust device; the downlink signal of the transmitting link processed by the power detect device and be transmitted to the power detect signal feed device, and then transmitted to the signal synthesize device; signal synthesize device depart the part of radio frequency signal, output to the power detect device for the power detect; output the power signal to the power detect signal feed device, add the power signal and high frequency signal, power detect signal depart device pick the power signal from the mixed signal, regulate the weight of the adjustment. This invention never use the special adjust signal transmitting device and becoming antenna, placed by using method of signal power detect to calculate the adjust weight value and transmitting phase adjust weight value of the transmit gain, the speed of the constringency become faster.

The invention discloses a method for improving the performance of a feedforward narrow-band active noise control system, which relates to the field of active noise control, and aims at the situation that the reference signal frequency acquired by a non-acoustic sensor in the feedforward narrow-band active noise control system with a minor access road on-line identification function and the target noise actual frequency are imbalanced and the problem the auxiliary noise brought by the minor access road on-line identification seriously hinders the reduction of the residual noise energy of the system. The control system comprises a frequency compensation subsystem, a signal synthesis subsystem and a minor access road on-line identification subsystem; the frequency compensation subsystem comprises a second-order autoregression module and a least mean square (LMS) algorithm module; the frequency compensation subsystem transmits the cosine component and sinusoidal component of the adjusted reference signal of an ith frequency channel to the signal synthesis; when the frequency imbalance reaches above 50%, the target noise can still be effectively restrained; and when in a steady state, the residual noise energy of the system is reduced to an ideal level, so that the performance of the control system can be further improved and is closer to the practice.

An ultrasonographic method includes: a first encoding transmission / reception step for transmitting an ultrasonic beam encoded by an encoding set consisting of a plurality of modulation codes in which at least two are in complementary relationship and demodulating reception signals corresponding to the ultrasonic beam; a step for obtaining a first synthesis signal by synthesizing the demodulation signals demodulated by the first encoding transmission / reception step; a second encoding transmission / reception step for transmitting an ultrasonic beam encoded by a reverse encoding set consisting of a plurality of modulation codes in which the arrangement order of modulation codes of the encoding set is reversed and demodulating the reception signals corresponding to the ultrasonic beam; a step for obtaining a second synthesis signal by synthesizing the demodulated signals demodulated by the second encoding transmission / reception step; a step for obtaining a third synthesis signal by synthesizing the first synthesis signal and the second synthesis signal; and a step for reconstructing the ultrasonograph according to the third synthesis signal.

The invention discloses an economizer of an alternative-current contactor, and the economizer comprises a peripheral circuit which is connected with the alternative-current contactor and a signal processor which is connected with the peripheral circuit; the signal processor comprises a comparison circuit, a zero-crossing detection circuit, a pulse width modulation circuit, a selection circuit, a low-voltage detection circuit and a signal synthesis circuit. Due to the adoption of the economizer, narrow pulse of small current passing through the alternative-current contactor can be changed along with the variation of external voltage, the width of the narrow pulse is reduced while the external voltage is increased, the current passing by the economizer is reduced, and thus the burning of the coil caused by the overlarge current can be avoided. When the external voltage is dropped, the width of the narrow pulse outputted by the economizer is increased, the current passing by the alternative-current contactor is correspondently increased, and thus the disconnection of the alternative-current contactor because of reduced current can be prevented; and moreover, the power consumption of the alternative-current contactor can be further reduced, and the burning of a contactor coil because of over-current can be avoided.

A video projector includes a display device which receives an image signal and generates image light projected onto a projection surface. A scaling processor scales the input image signal. An OSD processor generates and corrects an adjustment pattern image in accordance with a correction instruction on the projection surface. An image signal synthesizer combines the image signal processed by the scaling processor with an OSD image signal generated and corrected by the OSD processor to generate a combined image signal. A trapezoidal distortion corrector performs trapezoidal distortion correction on the combined image signal from the image signal synthesizer based on the correction of the adjustment pattern image on the projection surface. The adjustment pattern image generated by the OSD processor includes a reference quadrangle pattern and downsized quadrangle patterns, which are reduced in size from the reference quadrangle pattern.

The invention discloses an antenna feeder tester and an extending device error correction method by using the antenna feeder tester. The antenna feeder tester comprises a signal synthesis module, a power divider, a directional coupler, a test port, an amplitude and phase receiver module, an FPGA digital intermediate frequency processor and a CPU controller, wherein the signal synthesis module comprises an excitation signal source and a local vibration signal source; and the amplitude and phase receiver module comprises an R channel and an A channel, and one A / D conversion module is arranged behind each of the R channel and the A channel. During measurement, after correction is finished at the test port of the instrument, the antenna feeder tester of the invention is then used to measure transmission parameters of an extending device in the case when the extending device is connected, the transmission parameters of the extending device are used for correcting test data when the extending device is connected with a tested piece according to a theoretical loss formula of a cable, correction does not need to be carried out again, and the measurement precision and the test efficiency are thus improved.