公开(公告)号：DE19534262C2

公开(公告)日：1999-09-02

申请号：DE19534262

申请日：1995-09-15

Applicant: ADVANTEST CORP

Inventor： NAGANO MASAO ,  TAKAHASHI HITOSHI

IPC: G01R23/02 ,  H04B17/00 ,  G01R29/06

公开(公告)号：DE19745391A1

公开(公告)日：1998-04-23

申请号：DE19745391

申请日：1997-10-14

Applicant: ADVANTEST CORP

Inventor： NAGANO MASAO

IPC: G01R23/173 ,  G01R23/167 ,  H03H17/00 ,  H03H17/06 ,  H03H15/00 ,  G01R23/165

Abstract: The filter has at least one analogue FIR filter for limiting the intermediate frequency to a predefined band. There are analogue FIR filters for processing the equiphase signals and the quadrature signals at the intermediate frequency. The decimation filter also has a frequency filter for generating a clock signal which is fed to the analogue FIR filter or filters.

公开(公告)号：DE19534262A1

公开(公告)日：1996-03-28

申请号：DE19534262

申请日：1995-09-15

Applicant: ADVANTEST CORP

Inventor： NAGANO MASAO ,  TAKAHASHI HITOSHI

IPC: G01R23/02 ,  H04B17/00 ,  G01R29/06

Abstract: The swing measurement device contains an analogue-to-digital converter (17) which converts a FM input signal into a digital signal, a quadrature detector (19) for computing an in-phase component and quadrature component of the FM signal, a phase computation device (20), a differential computation device (21) and a frequency swing computation device (25,27-29). The phase computation device computes the instantaneous phase of the FM input signal from the quadrature and in-phase components. The differential computation device computes the instantaneous frequency of the modulated signal by differentiating time-serial instantaneous phase data. The frequency swing computation device computes the frequency fluctuation amplitude from the instantaneous frequency of the modulated signal to determine the maximum frequency swing.

公开(公告)号：DE19523343A1

公开(公告)日：1996-01-04

申请号：DE19523343

申请日：1995-06-27

Applicant: ADVANTEST CORP

Inventor： NAGANO MASAO

IPC: G01R29/00 ,  G01R23/165 ,  G01R29/08 ,  H04B3/46 ,  H04B17/00 ,  G01R21/133 ,  H04B7/212 ,  H04J3/14

Abstract: A calculator consists of a mixer (8) which combines transmissions from the measured object (1) and from a receiving oscillator (6). A Hilbert converter (2) filters the appropriate frequencies to an analogue/digital converter (3) using a frequency scanning oscillator (7). A digital processor (4) analyses the data and sends the result to a display unit (5).

公开(公告)号：JP2001136217A

公开(公告)日：2001-05-18

申请号：JP31772599

申请日：1999-11-09

Applicant: ADVANTEST CORP

Inventor： NAGANO MASAO

IPC: H04L27/18 ,  H04L27/22

Abstract: PROBLEM TO BE SOLVED: To estimate the phase deviation of a wide-band high frequency phase modulation signal and the jitter of a high speed clock signal. SOLUTION: This device analyzes the spectrum of an input signal (12), decides each sideband wave level when the input signal is regarded as a phase modulation signal (19), calculates covariance between its sideband wave level group (spectrum amplitude) and a Bessel function value by a modulation index, calculates a modulation index in which covariance becomes minimum (21), calculates a time base waveform by applying the spectrum to inverse Fourier transform (24) and decides the code of each spectrum according to the code of a Bessel function by using the calculated modulation index in such a case. The device calculates phase deviation ϕ (t) from the imaginary part and real part of the time base waveform (25) and defines a value ϕp-p obtained by subtracting a minimum value ϕmin of the ϕ(t) from a maximum value ϕmax as the phase deviation of the input signal or jitter quantity (26).

公开(公告)号：JPH0888515A

公开(公告)日：1996-04-02

申请号：JP22306994

申请日：1994-09-19

Applicant: ADVANTEST CORP

Inventor： NAGANO MASAO ,  TAKAHASHI HITOSHI

IPC: G01R29/06 ,  G01R23/02 ,  H03D3/00 ,  H03M1/64 ,  H04B17/00

Abstract: PURPOSE: To reduce fluctuation due to the elapse of time by providing an IQ arithmetic means, a phase arithmetic means, a differentiation arithmetic means, and a shift quantity arithmetic means which calculates a peak value on the positive side and the one on the negative side of frequency shift from a modulated frequency. CONSTITUTION: An FM input signal is inputted to a Hilbert transformation part 9, and its common mode component I and orthogonal component Q are calculated, and they are called a pair of Hilbert transformation. The pairs of transformation I, Q are inputted to a phase arithmetic part 10, and an instantaneous phase is calculated, and the time series data of instantaneous phase is inputted to a differentiation arithmetic part 11, then, the modulated frequency fa (t) is calculated. The time series data of modulated frequency fa (t) is inputted to and corrected by a carrier frequency error elimination part 12. The modulated frequency fa (t) is inputted to a BPF 14 via a de-emphasis part 13, and its noise component is eliminated, and a frequency of the high end is also limited, and it is inputted to a shift quantity arithmetic part 15. The arithmetic part 15 calculates the peak value P on the positive side and the peak value P on the negative side of frequency shift, and data with respect to them are inputted to a display device 16, then, they are displayed on a screen.

公开(公告)号：JPH0635672A

公开(公告)日：1994-02-10

申请号：JP19081592

申请日：1992-07-17

Applicant: ADVANTEST CORP

Inventor： NAGANO MASAO

IPC: G06F7/487 ,  G06F7/52

Abstract: PURPOSE:To efficiently attain a high speed Fourier transformation arithmetic processing which operates an arithmetic processing in which the number of a multiplication processing is extremely large by operating a floating point arithmetic operation only for a multiplication processing. CONSTITUTION:This device is equipped with a size discriminating equipment 200 which inputs a binary number indicated by a fixed point, left-shift circuits 201, 202, and 203 which left-shift the binary number smaller than a certain value, multiplier 204 which operates the arithmetic processing of the outputs of the left-shift circuits, and right-shift circuit 207 which right-shifts the output of the multiplier 204. Both the input and output are indicated by the fixed point, and the floating point arithmetic processing is operated for the multiplication. In the case of the multiplication, when 32 bit data are smaller than the certain value, the data are left-shifted before the arithmetic processing, and right-shifted after the arithmetic processing. An arithmetic speed is close to that in the case of the fixed point indication, and an arithmetic precision is equivalent to that in the case of the floating point indication.

公开(公告)号：JPH0526919A

公开(公告)日：1993-02-05

申请号：JP17676591

申请日：1991-07-17

Applicant: ADVANTEST CORP

Inventor： NAGANO MASAO

IPC: G01R23/16 ,  G01R23/173

Abstract: PURPOSE:To obtain a spectrum analyzer of which the measuring level accuracy is improved by correcting a scallop loss being inherent in fast Fourier transform. CONSTITUTION:A spectrum analyzer is equipped with an analog-digital converter 9 subjecting an input signal to analog-digital conversion and a memory 11 storing temporarily digital data obtained from the analog-digital conversion. Moreover, it is equipped with a multiplier which multiplies the digital data stored in the aforesaid memory 11 by a Gaussian function as a windowfunction, a fast Fourier transform unit which applies a fast Fourier transform processing to the result of multiplication of the digital data by the window function, an interpolating processor which applies an interpolation processing by tertiary function approximation to the result of the fast Fourier transform processing and a display unit 13 displaying the result of the interpolation processing.

公开(公告)号：JPH046956B2

公开(公告)日：1992-02-07

申请号：JP6955884

申请日：1984-04-06

Applicant: ADVANTEST CORP

Inventor： NAGANO MASAO

IPC: G09G5/00 ,  G01R13/20 ,  G09G1/00 ,  G09G5/36 ,  G09G5/395 ,  G09G5/42

公开(公告)号：JPH10126217A

公开(公告)日：1998-05-15

申请号：JP27240996

申请日：1996-10-15

Applicant: ADVANTEST CORP

Inventor： NAGANO MASAO

IPC: G01R23/173 ,  G01R23/167 ,  H03H17/00 ,  H03H17/06

Abstract: PROBLEM TO BE SOLVED: To eliminate the need for adjustment and temperature drift of a filter by increasing the processing speed of filter processing. SOLUTION: An intermediate frequency IF, (e.g. 21.4MHz that may be changed as required) used for a conventional spectrum analyzer, is mixed at a mixer Mix with a local oscillating frequency from a local oscillator Local 1, and its base band signal I passes sequentially through elements RBW1, RBW2,..., RBWn which are analog digital filters(ADF) and a filter of narrow band sequentially, and the base-band signal I passing through the element RBWn at the final stage is amplified by a logarithmic amplifier AMP. A detector DT is used to detect power, that is, a spectrum component and the result is converted into a digital signal by an A/D converter AD.