公开(公告)号：JPH0980092A

公开(公告)日：1997-03-28

申请号：JP23167895

申请日：1995-09-08

Applicant: ADVANTEST CORP

Inventor： FUKUI TAKAMASA ,  YAMASHITA KOICHI ,  YAMAGUCHI TAKAHIRO ,  AOYAMA OSAMU ,  KOSUGE TAKASHI ,  MIYAMAE YOSHIAKI ,  KASAHARA TOSHIHARU ,  TAKAOKU HIROAKI

IPC: G01R23/173 ,  G01R29/26

Abstract: PROBLEM TO BE SOLVED: To automatically determine the pass band width(RBW) or the like of a spectrum analyzer by determining RBW of BPF on the basis of the frequency interval of a waveform to be displayed, the noise level or the like. SOLUTION: RBW of BPFs 19, 24 of a spectrum analyzer 15 is made a parameter, and RBW is determined from the frequency interval of the waveform to be displayed so as to satisfy the relation with the frequency interval of the waveform to be displayed and the noise level or the dynamic range of an input signal. In other words, a control part 31 reads the spectrum of the input signal from a buffer memory 29, detects a frequency with its maximum value and makes it a central frequency. The central frequency is stored in a parameter value storing part 36. When the central frequency is determined, the input signal is measured again so that the central frequency may be in the center of a display scope and stored in a buffer memory 29. A noise part to be measured is made an offset value, three times thereof a frequency span, and RBW of BPFs 19, 24 is determined.

公开(公告)号：JP2575754B2

公开(公告)日：1997-01-29

申请号：JP29431887

申请日：1987-11-20

Applicant: ADVANTEST CORP

Inventor： YAMAGUCHI TAKAHIRO ,  KASAHARA TOSHIHARU ,  OZAWA HIROMI

IPC: G01R27/28 ,  G01H17/00 ,  G01M7/02 ,  G01R23/16

公开(公告)号：JPH0980100A

公开(公告)日：1997-03-28

申请号：JP23169195

申请日：1995-09-08

Applicant: ADVANTEST CORP

Inventor： FUKUI TAKAMASA ,  YAMASHITA KOICHI ,  YAMAGUCHI TAKAHIRO ,  AOYAMA OSAMU ,  KOSUGE TAKASHI ,  MIYAMAE YOSHIAKI ,  KASAHARA TOSHIHARU ,  TAKAOKU HIROAKI

IPC: G01R23/173 ,  G01R29/26

Abstract: PROBLEM TO BE SOLVED: To simply show time progress of noise level change by displaying the spectrum waveform of an input signal on one half part of a display screen and displaying noise on the other half part in a time domain. SOLUTION: A carrier frequency is positioned in the center of the left half of a display screen, and frequencies upward and downward separated by an offset value fof from the carrier frequency on both ends, and each spectrum therebetween is displayed. In other words, a spectrum waveform (frequency region) is displayed. In addition, the level of noise of a frequency fN upward separated by the offset value fof from the carrier frequency is displayed in time domain on the right half part of the display screen. In spectrum display for the frequency region of the left half part, frequency sweep is performed at least between fc ±Fof in regard to an input signal, necessary parts are taken out from data taken in a backup memory and are displayed. Taken-in display of the data for the left part display and the other taken-in display of the data for the right part display are performed alternately.

公开(公告)号：JPH0438477A

公开(公告)日：1992-02-07

申请号：JP14590490

申请日：1990-06-04

Applicant: ADVANTEST CORP

Inventor： KASAHARA TOSHIHARU

IPC: G01R27/28 ,  G01R31/00

Abstract: PURPOSE:To shorten a measuring time by subjecting the response output from an audio amplifier due to the input of an impulse wave to discrete Fourier transformation and calculating a phase with respect to respective required frequency components from a complex spectrum to calculate the delay time difference between other respective frequency components to a reference frequency component. CONSTITUTION:An analogue impulse wave is inputted to an audio amplifier 12 to be measured from a signal generator 14. The impulse response output of the audio amplifier 12 to be measured at this time is converted to a digital signal by an A/D converter to be subjected to Fourier transform by a discrete Fourier transformation device 16 like an FFT. The impulse wave is a multiple sine wave having infinite frequency components respectively starting from a zero phase and the complex spectra of respective frequency components are obtained from the transformation device 16. From the real and imaginary parts of the complex spectra with respect to required frequencies among them, for example, 1 kHz, the phases of said frequencies (spectra) are operated and the delay time of these phases is operated. For example, 1 kHz is set to reference frequency and the delay time differences with other frequency components to the reference frequency are respectively calculated. By this method, the delay time of each required frequency can be obtained by one measurement and a measuring time can be markedly shortened. Further, a delay time can be measured even in such a case that the audio amplifier to be measured is digital input and output.

公开(公告)号：JPH01136076A

公开(公告)日：1989-05-29

申请号：JP29431887

申请日：1987-11-20

Applicant: ADVANTEST CORP

Inventor： YAMAGUCHI TAKAHIRO ,  KASAHARA TOSHIHARU ,  OZAWA HIROMI

IPC: G01R27/28 ,  G01H17/00 ,  G01M7/02 ,  G01R23/16

Abstract: PURPOSE:To achieve a higher measuring accuracy and higher resolutions, by shifting address generating means for generating waveforms in generation reference by (n) frame from one another when a memory waveform is read out of a plurality of waveform generators to be supplied to an object to be measured. CONSTITUTION:A memory waveform of a waveform generator 11 composed of a ROM or a RAM is read out according to an address of an address generation means 12 as updated by a fixed clock and supplied to an object 15 to be measured via a data latch 13 and a D/A converter 14. A memory waveform of an identical waveform generator 12 is supplied to the object 15 being measured via a latch 19 and a D/A converter 21. Since an address of a waveform generator 16 is given as the sum of an output of an address generation means 17 and a value of an offset memory 24 as altered by (n) frames, outputs of the waveform generators 11 and 16 provide a prime to each other. A response waveform of the object 15 being measured is applied to a Fourier transform means 25 to compute a frequency response function.

公开(公告)号：JPH07134151A

公开(公告)日：1995-05-23

申请号：JP27978293

申请日：1993-11-09

Applicant: ADVANTEST CORP

Inventor： YAMAGUCHI TAKAHIRO ,  FUKUI TAKAMASA ,  KASAHARA TOSHIHARU ,  YAMASHITA KOICHI ,  AOYAMA OSAMU ,  KOSUGE TAKASHI ,  MIYAMAE YOSHIAKI ,  TAKAOKU HIROAKI

IPC: G01R23/16 ,  G01R23/173

Abstract: PURPOSE:To store analytical conditions for high speed measurement and a plurality of precise measurements in an analytical condition memory means, successively store each analytical condition in each setting memory means, read the results obtained by frequency analysis according to respective analytical conditions into an image memory, and display a plurality of measurement results on one screen. CONSTITUTION:An analytical condition file for high speed measurement is stored in the memory area 200A of an analytical condition memory means 200, and analytical condition files for precise measurement are stored in the memory area 200B-200D. After the analytical conditions are stored in each memory area 200A-200D, the mode is switched to automatic measurement mode. A controller 115 successively reads the analytical condition files for high speed measurement and precise measurement, temporarily stores them in setting memory means 106, 107, 112, 117, 118, and performs frequency analysis according to the analytical conditions. The results are stored in four memory areas of an image memory 300. Thus, one or a plurality of the measurement results can be displayed in one screen of an indicator 301.

公开(公告)号：JPH04229B2

公开(公告)日：1992-01-06

申请号：JP18164183

申请日：1983-09-28

Applicant: ADVANTEST CORP

Inventor： YAMAGUCHI TAKAHIRO ,  OGAWA MASAYUKI ,  KASAHARA TOSHIHARU

IPC: G01R27/28 ,  G01R23/16

公开(公告)号：JPS6340869A

公开(公告)日：1988-02-22

申请号：JP18451986

申请日：1986-08-06

Applicant: ADVANTEST CORP

Inventor： YAMAGUCHI TAKAHIRO ,  OZAWA HIROMI ,  OGAWA MASAYUKI ,  KASAHARA TOSHIHARU

IPC: G01R23/16 ,  G01R23/20 ,  G11B20/18

Abstract: PURPOSE:To enhance accuracy, by forming the anti-phase signal of the fundamental wave of a response output signal to remove the fundamental wave component. CONSTITUTION:A sine wave signal is applied to a body 3 tested by a signal generating means 100. The response output signal of the body 3 tested is inputted to the input terminal A of a measuring means 400 and subjected to frequency analysis to be stored. A sine wave signal having the same frequency as the signal from the means 100 is generated from a division signal generating means 200 to be inputted to the means 400 through an adder means 300 and compared with an amplitude value Ap stored already and the comparing result is transmitted to CPU131 to set a gain or attenuation quantity for generating a division signal having amplitude equal to Ap to the means 200. By turning a switch SW-O ON in such a state that the division signal is outputted from the means 200, a signal to be measured and the division signal are applied to the adder means 300 and the greater part of a fundamental wave is removed from the signal to be measured. Since only a high frequency waveform which the fundamental wave is removed is inputted to a measuring means 400, measuring accuracy is enhanced.