公开(公告)号：EP0547228A4

公开(公告)日：1994-07-13

申请号：EP92910579

申请日：1992-05-26

Applicant: ADVANTEST CORP

Inventor： HIROSE MASAAKI ,  KATOH KAZUO ,  UEKI YUTAKA ,  HIRAKOSO YOHEI ,  SATOH MITSUNORI ,  KOSUGE TAKASHI

IPC: G01R19/00 ,  G01R29/08 ,  G01R29/26

CPC classification number: G01R19/003 ,  G01R29/0892 ,  G01R29/26

公开(公告)号：DE19542247A1

公开(公告)日：1996-05-15

申请号：DE19542247

申请日：1995-11-13

Applicant: ADVANTEST CORP

Inventor： KOSUGE TAKASHI

IPC: G01R23/173

Abstract: A spectrum analyser for measuring the frequency of input signals blocks the display of unwanted mirror frequencies by the use of a wobbulator (13) with a local oscillator (56). This generates spectra within the frequency range under investigation which are mixed with the incoming signals at an external frequency mixer (72). These doubled signals are recognised and eliminated by the processor (12) prior to the spectrum display.Thus without the wobbulator-generated signals mirror frequencies across a range (Fig. 2a, fN4 a-d, fN5 a-d etc.) may give rise to confusing spectra, whereas the elimination of mixed frequencies following the use of the wobbulator-controlled oscillator and processor leads to a clear spectrum presentation (Fig. 2b, fN5b-c).

公开(公告)号：DE19542247C2

公开(公告)日：2000-12-07

申请号：DE19542247

申请日：1995-11-13

Applicant: ADVANTEST CORP

Inventor： KOSUGE TAKASHI

IPC: G01R23/173

公开(公告)号：DE19849524A1

公开(公告)日：1999-05-06

申请号：DE19849524

申请日：1998-10-27

Applicant: ADVANTEST CORP

Inventor： ARAI MICHIAKI ,  KOSUGE TAKASHI

IPC: G01R23/173 ,  G01R23/16 ,  G01R29/00

Abstract: The output signal of a frequency converter (13) for selecting the frequency is fed to an A/D converter (31). If a converter overflow condition results a level adjusting device adjusts the first stage of the spectral analyzer to prevent this. The output signal level of the frequency converter is adjusted so that the input signal level to the A/D converter always lies in the normal operating level range of the A/D converter.

公开(公告)号：DE19635890C2

公开(公告)日：2001-10-18

申请号：DE19635890

申请日：1996-09-04

Applicant: ADVANTEST CORP

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

IPC: G01R23/16 ,  G01R29/26 ,  G01R23/20

公开(公告)号：DE69228232T2

公开(公告)日：1999-07-08

申请号：DE69228232

申请日：1992-05-26

Applicant: ADVANTEST CORP

Inventor： HIROSE MASAAKI ,  KATOH KAZUO ,  UEKI YUTAKA ,  HIRAKOSO YOHEI ,  SATOH MITSUNORI ,  KOSUGE TAKASHI

IPC: G01R19/00 ,  G01R29/08 ,  G01R29/26

Abstract: An apparatus for measuring the intensity of an interfering electromagnetic wave, specifically for measuring the average value of impulsive noises in a short time accurately. In the apparatus, impulsive noises, inputted through a variable attenuator (12), a frequency converter (13), an intermediate-frequency amplifier (15), a band-pass filter (16) of 9 KHz or 120 KHz are inputted into a linear detector (17). The detected outputs are passed through a low-pass CR filter (31) whose cut-off frequency is tens of thousands of hertz to lower their peak values and to widen their width. The output of the filter is converted into digital signal by an A/D converter (33), and digital values at respective sampling points in one frame of the digital signals are summed by a computing circuit (34). Then, the summation value thereof is divided by the number of samples to obtain the average value and the result is displayed.

公开(公告)号：DE69228232D1

公开(公告)日：1999-03-04

申请号：DE69228232

申请日：1992-05-26

Applicant: ADVANTEST CORP

Inventor： HIROSE MASAAKI ,  KATOH KAZUO ,  UEKI YUTAKA ,  HIRAKOSO YOHEI ,  SATOH MITSUNORI ,  KOSUGE TAKASHI

IPC: G01R19/00 ,  G01R29/08 ,  G01R29/26

Abstract: An apparatus for measuring the intensity of an interfering electromagnetic wave, specifically for measuring the average value of impulsive noises in a short time accurately. In the apparatus, impulsive noises, inputted through a variable attenuator (12), a frequency converter (13), an intermediate-frequency amplifier (15), a band-pass filter (16) of 9 KHz or 120 KHz are inputted into a linear detector (17). The detected outputs are passed through a low-pass CR filter (31) whose cut-off frequency is tens of thousands of hertz to lower their peak values and to widen their width. The output of the filter is converted into digital signal by an A/D converter (33), and digital values at respective sampling points in one frame of the digital signals are summed by a computing circuit (34). Then, the summation value thereof is divided by the number of samples to obtain the average value and the result is displayed.

公开(公告)号：DE19635890A1

公开(公告)日：1997-03-13

申请号：DE19635890

申请日：1996-09-04

Applicant: ADVANTEST CORP

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

IPC: G01R23/16 ,  G01R29/26 ,  G01R23/20

Abstract: The passband of two filters (19,24) is adjusted automatically so that a relationship between a waveform to be displayed (35) and a noise level or dynamic range is fulfilled. The bandwidth of a low-pass filter (27) for the output from a demodulator is set to one-tenth of the passband. A frequency span is fixed at three times the frequency interval. The frequency at which the highest peak level of the input signal occurs is found and selected as the central frequency of the display.

公开(公告)号：JPH11133072A

公开(公告)日：1999-05-21

申请号：JP29435097

申请日：1997-10-27

Applicant: ADVANTEST CORP

Inventor： ARAI MICHIAKI ,  KOSUGE TAKASHI

IPC: G01R23/173 ,  G01R23/16

Abstract: PROBLEM TO BE SOLVED: To automatically set a reference level. SOLUTION: An output of an initial stage frequency conversion means 13 is branched, and is further subjected to frequency conversion and is taken into a memory 35 as digital data by an A/D converter 31. A DSP 36 reads the digital data, judges whether the converter 31 overflowed or not, adds 10 dB to an initial stage attenuator 12 if the converter 31 overflowed, reads data again, examines whether a peak value is within 85-65% of the full scale of the A/D converter if the converter 31 was not overflowed, performs calculation so that the peak value is within the range if the peak value is not within the range, adds/subtracts the gain of an amplifier 15, and uses the peak value as a reference level if the value is within the above range.

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.