公开(公告)号：DE19804571C2

公开(公告)日：2000-06-08

申请号：DE19804571

申请日：1998-02-05

Applicant: ADVANTEST CORP

Inventor： DOI WATARU

IPC: G01R23/00 ,  G01R23/173 ,  G01R23/165

Abstract: A spectrum analyzer measures a time difference between two or more signals with different carrier frequencies or a time delay between two or more signals with the same carrier frequency. The spectrum analyzer includes at least two measurement channels, each of the measurement channels has a frequency mixer, a local oscillator and an IF (intermediate frequency) filter for mixing an input signal to be measured with a local signal of the local oscillator to produce an IF signal which passes through the IF filter, and a demodulator provided in one of the measurement channels to demodulate the IF signal produced from the input signal to generate a trigger signal to start an operation of the other measurement channel.

公开(公告)号：DE19804571A1

公开(公告)日：1998-08-20

申请号：DE19804571

申请日：1998-02-05

Applicant: ADVANTEST CORP

Inventor： DOI WATARU

IPC: G01R23/00 ,  G01R23/173 ,  G01R23/165

Abstract: The spectrum analyser has at least two measuring channels (CH1,CH2). Each channel contains a frequency mixer (11,12), an auxiliary oscillator (21,22) and an IF (intermediate frequency) filter (31,32), for mixing an input signal to be measured with an auxiliary oscillator signal to provide an IF signal fed through the filter. One of the measuring channels contains a demodulator (70) for demodulation of the IF signal (100) and provision of a trigger signal, which initiates the operation of the other measuring channel.

公开(公告)号：DE112009002185T5

公开(公告)日：2011-11-17

申请号：DE112009002185

申请日：2009-09-14

Applicant: ADVANTEST CORP

Inventor： AOYAMA SATORU ,  DOI WATARU

IPC: G01R23/173

Abstract: Es wird eine Frequenzcharakteristik-Messvorrichtung geschaffen, die die Konfiguration zum Ausführen einer Messung vereinfachen und die für die Messung erforderliche übermäßige Anstrengung verringern kann. Ein Spektrumanalysator (10) umfasst: zwei Sätze von Messeinheiten, die Mischer (110, 210), Lokaloszillatoren (112, 212) und ZF-Abschnitte (120, 220) zum getrennten Messen der Frequenzcharakteristiken zweier Eingangssignale aufweisen; einen Triggersteuerabschnitt (350), der ein Triggersignal zum Spezifizieren eines Messanfangszeitpunkts in jedem der zwei Sätze von Messeinheiten erzeugt, einen Wobbelsteuerabschnitt (300), der eine Anweisung gleichzeitig an die zwei Lokaloszillatoren (112, 212) sendet, wenn ein Triggersignal eingegeben wird, und eine Wobbelsteuerung in der Weise ausführt, dass die zwei Lokaloszillatoren (112, 212) zum selben Zeitpunkt Lokaloszillationssignale mit derselben Frequenz ausgeben.

公开(公告)号：DE19734040C2

公开(公告)日：1999-09-30

申请号：DE19734040

申请日：1997-08-06

Applicant: ADVANTEST CORP

Inventor： DOI WATARU

IPC: G01R23/16 ,  G01R23/173 ,  H04N17/00 ,  H04N17/02

Abstract: A received signal is converted in a frequency converter, an output from which is again frequency converted. The second converted output is detected by a detector and then converted into a digital signal to be stored in a memory. A spectrum display is provided by a display. A frequency sweep of local signals supplied to frequency converter is enabled. While holding the frequency sweep for the earlier stage suspended to receive one of the radio waves in service, a signal to the input of the frequency converter may be branched and demodulated by demodulation means. A vertical sync signal is separated in monitor processing means and the frequency of the local signal generator may be swept only during a no-modulation interval contained in a vertical blanking interval, thus extracting a carrier component and a noise component, the levels of which are determined to provide a measure of C/N.

公开(公告)号：DE19734040A1

公开(公告)日：1998-02-12

申请号：DE19734040

申请日：1997-08-06

Applicant: ADVANTEST CORP

Inventor： DOI WATARU

IPC: G01R23/16 ,  G01R23/173 ,  H04N17/00 ,  H04N17/02

Abstract: The analyser includes two frequency converters (17,22). The frequency of a modulated signal at the input to the second frequency converter is wobbled, while the modulation frequency of the signal at the first frequency converter is held constant in order to determine the input signal frequency. The output signal from the first frequency converter is branched off to a demodulator (41) in order to monitor the demodulated signal (44). For TV signals the analyser can determine the in-band noise level during unmodulated interval, and the peak picture carrier signal. The signal-to-noise ratio is calculated and displayed.

公开(公告)号：DE102009000477A1

公开(公告)日：2009-09-03

申请号：DE102009000477

申请日：2009-01-29

Applicant: ADVANTEST CORP

Inventor： DOI WATARU ,  HIRAKOSO YOHEI

IPC: G01R23/173

公开(公告)号：JPH10282163A

公开(公告)日：1998-10-23

申请号：JP871798

申请日：1998-01-20

Applicant: ADVANTEST CORP

Inventor： DOI WATARU

IPC: G01R23/173

Abstract: PROBLEM TO BE SOLVED: To measure the time difference between two signals with different carrier frequencies, and a time delay between signals with the same frequency by demodulating an IF signal of one channel and supplying it as a trigger signal common to all channels. SOLUTION: An IF signal 100 of the output of an IF filter 31 is demodulated by a demodulator 70 and a trigger signal 200 is generated, thus synchronizing the sweeping start of ramp wave generators 61 and 62. The demodulator 70 has a function for demodulating an original signal from the modulated carrier wave, thus further generating another trigger signal from the demodulation signal of the IF signal 100. Each signal input terminal receives the signals of each reference control channel and communication channel in the order of channels 1 and 2, frequencies are turned to frequencies f1 and f2, and a desired sweep time is set as zero frequency span, namely a zero span. As a result, the reference control channel of the frequency f1 and the information of the communication channel of the frequency f2 are displayed at a display part 80, thus measuring a time delay.

公开(公告)号：JPH04221711A

公开(公告)日：1992-08-12

申请号：JP40504890

申请日：1990-12-21

Applicant: ADVANTEST CORP

Inventor： DOI WATARU

IPC: G01D1/12

Abstract: PURPOSE:To surely take in a narrow positive pulse-like portion produced when an input signal is in the negative ramp state. CONSTITUTION:In a signal take-in circuit in which output of a sample hold circuit 15 and an input signal are compared by a ramp detector 21, when the input signal is larger, a positive peak detection circuit 12 is connected to the sample hold circuit 15, and when the input signal is smaller, a negative peak detection circuit 13 is connected to the sample hold circuit 15, the output of the positive peak detection circuit 12 is differentiated by a differentiating circuit 35, and when the differentiated output pulse is more than a designated level, a pulse signal detection circuit 37 detects the existence of a positive pulse-like portion in the input signal, and the positive peak detection circuit is connected to the sample hold circuit 15 according to the output regardless of the output state of the ramp detector 21.

公开(公告)号：JPH0431771A

公开(公告)日：1992-02-03

申请号：JP13802990

申请日：1990-05-28

Applicant: ADVANTEST CORP

Inventor： DOI WATARU

IPC: G01R19/04 ,  H03G3/30

Abstract: PURPOSE:To catch correctly a peak value of a pulse having a narrow pulse width as well and to detect the peak value of an input signal even in a reset state by detecting a peak of the input signal by a plurality of high-speed response type peak detecting circuits. CONSTITUTION:Two high-speed response type peak detecting circuits 10A and 10B are connected in parallel in the front stage of a low-speed response type peak detecting circuit 10C and these two high-speed response type peak detecting circuit 10A and 10B are made to conduct a reset operation alternately. Even when an input signal is present when either one of them is mutually in a rest period, the other high-speed response type peak detecting circuit is made to operate as a means to transmit the input signal to the low-speed response type peak detecting circuit in the rear stage.

公开(公告)号：JPH0266594A

公开(公告)日：1990-03-06

申请号：JP21892288

申请日：1988-08-31

Applicant: ADVANTEST CORP

Inventor： DOI WATARU

IPC: G09G5/10 ,  G09G5/00 ,  G09G5/36

Abstract: PURPOSE:To improve, specially, the brightness of only a single-shot signal by increasing the brightness of the display device when detecting dissidence between two successive data among output serial data. CONSTITUTION:Parallel data read out of a memory plane 12 is inputted from a shift register to a parallel-series converting circuit 13, where the data is shifted with a dot clock from a terminal 14 and outputted as serial data from an output terminal at one end. When the data of a spectrum part is inputted to the output terminal QD of the parallel-series converting circuit 13, its output data is 1, but this data is a single-shot signal, so data before and after said data, i.e. data at output terminals QE and QC are 0. The outputs of exclusive OR circuits 17 and 18 and '1' and a dissidence detecting circuit 21 detects their dissidence. Then its dissidence detection output is added to the data at the output terminal QD, so the current brightness of the display device 11 is high.