| Patent application number | Description | Published |
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| 20090273495 | ANALOG DIGITAL CONVERTING APPARATUS, ANALOG DIGITAL CONVERTING METHOD, TEST APPARATUS, PROGRAM AND RECORDING MEDIUM - Provided is an AD converting apparatus that converts an analog input signal into a digital output signal, comprising a plurality of AD converters that are supplied with sampling clocks differing from each other by a prescribed phase, and that each output an individual signal obtained by digitizing the input signal according to the sampling clock supplied thereto; a common compensating section that commonly compensates for prescribed common non-linear distortion in the individual signals; a plurality of individual compensating sections that each individually compensate for individual non-linear distortion in a corresponding one of the individual signals, the individual non-linear distortion obtained as a ratio between the non-linear distortion and the common non-linear distortion in each individual signal; and a combining section that combines the individual signals to generate the output signal. | 11-05-2009 |
| 20100060495 | ANALOG DIGITAL CONVERT APPARATUS, ANALOG DIGITAL CONVERT METHOD, CONTROL APPARATUS AND PROGRAM - Provided is an AD converting apparatus that converts an analog input signal into a digital output signal, comprising a plurality of AD converters supplied with sampling clocks differing from each other by prescribed phase amounts, each AD converter outputting an individual signal obtained by digitizing the input signal according to the supplied sampling clock; a plurality of amplitude-dependent characteristic correcting sections that are provided to correspond to the plurality of AD converters, each amplitude-dependent characteristic correcting section generating a corrected individual signal by correcting the individual signal output by the corresponding AD converter using a correction factor corresponding to an amplitude of the individual signal; and a combining section that generates the output signal by combining a plurality of the corrected individual signals. | 03-11-2010 |
| 20100250638 | SIGNAL PROCESSING APPARATUS, DIGITAL FILTER AND RECORDING MEDIUM - Provided is a signal processing apparatus for compensating for a non-linear distortion of a digital signal, including: an analysis signal generating section that converts the digital signal into a analysis signal of a complex number, using a digital filter; and a compensation section that compensates for the analysis signal, using a compensation coefficient of a complex number corresponding to the non-linear distortion, where the digital filter divides data of the digital signal into “n” data sequences, assigns (n*L+k)th data of the digital signal to a k-th data sequence, performs filtering on each of the data sequences using a same filter coefficient, and combines each of the data sequences after the filtering, thereby generating an imaginary number portion of the analysis signal, where “n” is an integer equal to or greater than 2, L=0, 1, . . . , and k=1, 2, . . . , n. | 09-30-2010 |
| 20100309952 | Distortion identification apparatus, test system, recording medium and distortion identification method - Provided is a signal output control section that inputs to a digitizer a reference signal whose frequency changes at each prescribed measurement cycle; a data extracting section that extracts a number of pieces of data corresponding to an integer multiple of a period of the reference signal in each measurement cycle, from pieces of data of a reference digital signal output by the digitizer according to the reference signal that come after a prescribed wait interval has passed since an initiation timing of each measurement cycle; a distortion identifying section that calculates the non-linear distortion caused by the digitizer for each frequency of the reference signal, based on the data in each measurement cycle extracted by the data extracting section; and a distortion calculating section that calculates the non-linear distortion caused by the digitizer when the analog signal input to the digitizer has a frequency that differs from any of the plurality of frequencies at which the reference signal transitions, based on the non-linear distortion detected by the distortion identifying section for each frequency. | 12-09-2010 |
| 20100310006 | Signal processing apparatus, test system, distortion detecting apparatus, signal compensation apparatus, analytic signal generating apparatus, recording medium and analytic signal generating method - Provided is a reference data converting section that rearranges each of a plurality of frequency components along the frequency axis such that (i) a fundamental wave component and harmonic wave components of a reference digital signal are within a first Nyquist region of a spectrum of the reference digital signal and (ii) image components of the fundamental wave component and the harmonic wave components are within a second Nyquist region of the spectrum; and a distortion detecting section that detects the non-linear distortion of the reference digital signal caused by each harmonic wave component, based on each harmonic wave component having a prescribed order number in the spectrum in which each frequency component has been rearranged by the reference data converting section. | 12-09-2010 |
| 20110022341 | MEASUREMENT APPARATUS, PROGRAM, RECORDING MEDIUM, AND MEASUREMENT METHOD - Provided is a measurement apparatus that measures a characteristic of an AD converter, comprising a signal supplying section that supplies the AD converter with an analog input signal having a prescribed waveform; an acquiring section that acquires a digital output signal output by the AD converter as a result of sampling the analog input signal; a measured histogram generating section that generates a histogram of the digital output signal; and a range calculating section that calculates at least one of an analog value corresponding to a lower limit and an analog value corresponding to an upper limit of a prescribed digital range, based on at least one of (i) a frequency corresponding to digital values, in a measured histogram obtained by measuring the digital output signal, that are less than or equal to the digital range and (ii) a frequency corresponding to digital values in the measured histogram that are greater than or equal to the digital range. | 01-27-2011 |
| Patent application number | Description | Published |
|---|
| 20080272942 | ANALOG TO DIGITAL CONVERTER AND RECORDING MEDIUM - An analog-to-digital conversion apparatus includes an interleaving section that aligns the digital data respectively output from a plurality of analog-to-digital conversion sections and generates a data sequence, and a correction arithmetic section that corrects a data value error caused by errors of frequency characteristics of the plurality of analog-to-digital conversion sections, in which the correction arithmetic section includes: a data partitioning section that generates a plurality of partition data by partitioning the data sequence, a data inserting section that inserts data with data value zero at the head or end of each of the partition data by a predetermined insertion data number to sequentially output these data, an arithmetic section that sequentially outputs data after correction made by sequentially performing correction arithmetic on the partition data, and a data connecting section that adds sequentially connects the data after correction and the data after correction following the data after correction. | 11-06-2008 |
| 20090043528 | TESTING APPARATUS AND TESTING METHOD - Provided is a test apparatus that tests a device under test that outputs a plurality of modulated signals modulated with carrier signals having frequencies identical to each other, including a synthesizing section that synthesizes the plurality of modulated signals to output a synthesized signal; an AD converting section that samples the synthesized signal to output a digital signal corresponding to the synthesized signal; and a judging section that judges acceptability of the plurality of modulated signals output by the device under test, based on the digital signal. | 02-12-2009 |
| 20090105977 | TEST APPARATUS, SKEW MEASURING APPARATUS, DEVICE AND BOARD - There is provided a test apparatus for testing a device under test, which includes a plurality of drivers which output signals to the device under test, an output control section which controls the plurality of drivers to output a plurality of signals respectively, a calculating section which calculates skews of the plurality of signals output from the plurality of drivers respectively, based on a combination signal obtained by combining the plurality of signals, and an adjusting section which adjusts the timings to output signals to be output from the plurality of drivers, based on the skews. | 04-23-2009 |
