Patent application number | Description | Published |
20090067485 | WAVEFORM EQUALIZING DEVICE - A waveform equalizing device for performing high-precision waveform equalization for an input signal and outputting the result as an output signal, includes: a FIR filter for performing convolution operation between the input signal and a plurality of tap coefficients; first and second slicers at least one of which makes decision on the value of the output signal; a first delay device for imparting a delay to the output of the second slicer; an IIR filter; and an addition section for summing the output of the FIR filter and the output of the IIR filter and outputting the sum as the output signal. The IIR filter includes first and second delay portions for respectively receiving the outputs of the first slicer and the first delay device and imparting delays, and performs convolution operation between the signal received by the first delay portion and tap coefficients for the first delay portion and between the signal received by the second delay portion and tap coefficients for the second delay portion. | 03-12-2009 |
20090070396 | WAVEFORM EQUALIZING DEVICE - Tap coefficients for a filter for removing a ghost signal are converged to optimum values in a short time. The waveform equalizing device includes: an initial tap coefficient generation section for determining and outputting the initial values of tap coefficients for a FIR filter and an IIR filter based on a plurality of correlation values; and a tap coefficient updating section for outputting the initial values of tap coefficients for the FIR filter and the IIR filter to these filters and updating tap coefficients for these filters based on error information. The initial tap coefficient generation section reverses the order of values, among the plurality of correlation values, corresponding to delays within a predetermined range to determine the order-reversed values as the initial values of tap coefficients for the FIR filter corresponding to the delays within the predetermined range, and also reverses the signs of values, among the plurality of correlation values, corresponding to delays exceeding the predetermined range to determine the sign-reversed values as the initial values of tap coefficients for the IIR filter. | 03-12-2009 |
20100013570 | WAVEFORM EQUALIZER - Tap coefficients of an FIR filter are prevented from converging to wrong values. A waveform equalizer for performing waveform equalization of an input signal and outputting a waveform equalization result as an output signal includes: an FIR filter for performing a convolution operation between the input signal and a plurality of tap coefficients; an IIR filter for performing a convolution operation between the output signal and a plurality of tap coefficients; an adding section for adding an operation result of the FIR filter and an operation result of the IIR filter and outputting an addition result as the output signal; an error detecting section for detecting an error of the output signal; and a tap coefficient updating section for updating respective tap coefficients of the FIR filter and the IIR filter based on the error. The tap coefficient updating section sets a step size for updating the tap coefficients of the FIR filter to a value smaller than a step size for updating the tap coefficients of the IIR filter during a period from start of operation of the waveform equalizer until a predetermined condition is satisfied. | 01-21-2010 |
20100045873 | VSB DEMODULATING APPARATUS AND TELEVISION RECEIVER - A VSB modulated signal is properly demodulated even when there is phase error variation in the VSB modulated signal. A VSB demodulator configured to demodulate a VSB modulated signal including a plurality of segments each having a predetermined segment synchronization component includes: a channel estimation section configured to generate a timing signal synchronous with the segment synchronization components; a phase variation detection section configured to detect a phase error in the VSB modulated signal in accordance with timing indicated by the timing signal, and output a detection signal corresponding to variation in the detected phase error; and a waveform equalization section, including a filter, configured to update a coefficient of the filter and perform waveform equalization on the VSB modulated signal. The waveform equalization section increases a coefficient update gain for the filter when the detection signal indicates that the variation in the phase error is larger than a predetermined value. | 02-25-2010 |
20100081484 | COMMUNICATION APPARATUS, SEMICONDUCTOR INTEGRATED CIRCUIT, AND ELECTRONIC DEVICE - A communication apparatus ( | 04-01-2010 |
20100323648 | DEMODULATION DEVICE, RECEPTION DEVICE, AND DEMODULATION METHOD - A device mitigates reduction in reception performance caused by a harmonic component of a clock used for demodulation. The device includes a tuner performing frequency conversion by multiplying a received signal by a signal having a frequency corresponding to a frequency of a desired signal included in the received signal, and outputting the obtained frequency-converted signal; and a demodulation section generating a demodulated signal by demodulating the frequency-converted signal. The demodulation section operates in response to a master clock having a frequency corresponding to the frequency of the desired signal. | 12-23-2010 |
20140192262 | VIDEO DEMODULATION DEVICE - A demodulator of a video demodulation device includes an analog-to-digital converter converting an analog IF signal into a digital IF signal, a luminance gain adjuster performing gain adjustment of a luminance component included in the digital IF signal such that a maximum of the luminance component within a predetermined period becomes equal to a predetermined reference value, and a synchronization corrector receiving as input a result of the gain adjustment, correcting a signal corresponding to a signaling period of the horizontal synchronizing signal, and outputting the signal as a CVBS signal. The synchronization corrector outputs, as the CVBS signal, a composite signal containing the luminance component and a color component included in the gain adjustment result when the composite signal is smaller than the reference value, or the reference value when the composite signal is equal to or greater than the reference value. | 07-10-2014 |
20150241564 | THREE-DIMENSIONAL MEASURING DEVICE AND THREE-DIMENSIONAL MEASURING METHOD - In a ranging system using a TOF method, an unwanted reflected light component included in reflected light is reduced or removed. A light source unit emits light at the timing indicated by a light emission control signal and can adjust for each of at least two irradiation regions the amount of light to be emitted. A light receiving unit is exposed to light from a region including a target object and produces three-dimensional information from the total exposure amount. An image processing unit generates a distance image based on the three-dimensional information received from the light receiving unit. The light source unit emits light according to a radiation pattern indicated by a region light amount signal. The radiation pattern is setting of the amount of light to be emitted to each irradiation region. | 08-27-2015 |