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公开(公告)号：JP2006338390A
公开(公告)日：2006-12-14
申请号：JP2005162966
申请日：2005-06-02
Applicant: Advantest Corp , 株式会社アドバンテスト
Inventor： KUMAGAI KENICHIRO , ARAI MICHIAKI
Abstract: PROBLEM TO BE SOLVED: To attain a logarithmic transformation highly precisely with a circuit configuration without using a CORDIC circuit. SOLUTION: The logarithmic transformation is performed by a detector of a bit position E for comparing binary data from higher-order bits and calculating and outputing a bit position E to be a first 1, a divider for taking a value obtained by dividing the data by the E-th power of 2 as a value of Mant, a storing means for preliminarily storing a base 2 logarithm of respective Mants in a table and reading the base 2 logarithm of Mant for a desired Mant with reference to the table, and an adding means for adding and outputing the logarithm of Mant read from the storing means to the calculated E. COPYRIGHT: (C)2007,JPO&INPIT
Abstract translation: 要解决的问题：使用电路配置高精度地进行对数变换而不使用CORDIC电路。 解决方案：对数变换由比特位置E的检测器执行，用于比较来自高阶比特的二进制数据，并计算和输出比特位置E为第一个1，分频器用于获取通过分割获得的值 以2的E次幂的数据作为Mant的值，存储装置，用于在表中预先存储各个Mant的基数2对数，并参考该表读取所需Mant的Mant的基数2对数， 以及添加装置，用于将从存储装置读取的Mant的对数相加和输出到计算的E.版权所有（C）2007，JPO＆INPIT
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公开(公告)号：JP2002026824A
公开(公告)日：2002-01-25
申请号：JP2000201214
申请日：2000-07-03
Applicant: ADVANTEST CORP
Inventor： ARAI MICHIAKI
IPC: H04L27/18 , H04B17/00 , H04B17/336 , H04L27/00
Abstract: PROBLEM TO BE SOLVED: To provide a C/N ratio-measuring instrument capable of obtaining the C/N ratio of a transmission line even in the state of actual operation. SOLUTION: The instrument is provided with a signal conversion part 31 for lowering the frequency of an RF signal and A/D-converting it to generate an IF signal, IQ orthogonal converters 35a, b for giving IQ-orthogonal conversion to the IF signal to generate passing signals Isig and Qsig, a demodulation part 34 for demodulating the passing signals to ideal signals Iref, Qref to return them to the ideal signals before orthogonal modulation, an ideal power calculation part 36 for calculating the power of the ideal signals, power calculation 32 for calculating noise power based on a value obtained by subtracting the ideal signals from the passing signals, and a C/N ratio calculation part 38 for calculating the C/N ratio from the power of the ideal signals and noise power. Thus, since the C/N ratio can be obtained, based on the power and noise power of the ideal signals which can be obtained without making a signal generator 110 stop signals, the C/N ratio of the transmission line 20 can be obtained even in a state of the actual operation.
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Patent Agency Ranking13.发明专利
公开(公告)号：JP2000307668A
公开(公告)日：2000-11-02
申请号：JP11251299
申请日：1999-04-20
Applicant: ADVANTEST CORP
Inventor： ARAI MICHIAKI , KURIHARA TOSHIAKI
Abstract: PROBLEM TO BE SOLVED: To measure the modulation precision of a TDMA communication system at a base station in an actual operation state and a mobile terminal in a packet communication state. SOLUTION: The device is equipped with a burst signal rise detection part 22 which detects a rise in a burst signal, a burst signal demodulation part 23 which demodulates the signal in the burst by slots from the rise, and a sink word detection part 24 which detects whether or not the signal in the demodulated burst contains a sink word to be measured. Even if one frame has multiple bursts, the sink word detection part 24 detects the word to be measured, so which burst the sink word to be measured is present can be detected, so the modulation precision in the actual operation state can be measured.
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公开(公告)号：JPH11331299A
公开(公告)日：1999-11-30
申请号：JP13500998
申请日：1998-05-18
Applicant: ADVANTEST CORP
Inventor： ARAI MICHIAKI
IPC: H04L27/38
Abstract: PROBLEM TO BE SOLVED: To attain analysis of 64 point QAM modulation. SOLUTION: A maximum amplitude and a minimum amplitude of base band I, Q input signals are retrieved (S5), a gain is decided so that the minimum amplitude is in matching with a minimum amplitude of 1st to 9th amplitudes taken in a 64 point QAM signal space (S6), the gain is multiplied with each symbol point string (S7), the symbol point string is phase-rotated by πi/256 rad each to produce an ideal symbol point string (S10). The correlation between this string and the original input symbol point string is obtained till an angle πi/256 reaches π/4, and the gain is decided so that the minimum amplitude is in matching with a 2nd standard amplitude (S15). Whether or not the product of the gain and the maximum amplitude is larger than a sum of a prescribed value to the standard maximum amplitude is discriminated (S17), and when larger, the phase rotation at that time is given to an input symbol to obtain a frequency error.
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公开(公告)号：JP2008107247A
公开(公告)日：2008-05-08
申请号：JP2006291724
申请日：2006-10-26
Applicant: Advantest Corp , 株式会社アドバンテスト
Inventor： ARAI MICHIAKI
IPC: G01D1/14
Abstract: PROBLEM TO BE SOLVED: To generate probability distribution with accuracy, even if the signal to be measured is a burst signal.
SOLUTION: An apparatus for measuring the probability distribution of the signal to be measured includes a sampling section for sequentially sampling the signal to be measured; a storage section having a plurality of addresses, corresponding to sample values of the signal to be measured, and storing storage values that represent the occurrence frequencies of the sample values to a plurality of the corresponding addresses; a storage value increase section for sequentially increasing the storage value stored at the address corresponding to the sampled sample value by a predetermined quantity, in response to the sequential sampling of the signal to be measured; a range setting section for setting address range in the storage section, corresponding to a range of the sample values estimated so as to be detected during the on-period of the burst signal, on the condition that the signal to be measured be a burst signal containing an on-period and an off-period; a probability distribution generating section for generating the probability distribution of the signal to be measured, based on the storage values stored in the address range.
COPYRIGHT: (C)2008,JPO&INPITAbstract translation: 要解决的问题：为了准确地产生概率分布，即使要测量的信号是突发信号。 解决方案：用于测量要测量的信号的概率分布的装置包括用于对要测量的信号进行顺序采样的采样部分; 存储部分，具有对应于要测量的信号的采样值的多个地址，并将表示采样值的出现频率的存储值存储到多个对应的地址; 存储值增加部分，用于响应于要测量的信号的顺序采样，将存储在与采样样本值相对应的地址上的存储值依次增加预定量; 一个范围设置部分，用于设置存储部分中的地址范围，对应于在脉冲信号的接通周期期间被检测的样本值的范围，在待测信号为突发信号的条件下 包含期间和期限; 概率分布生成部，其基于存储在地址范围中的存储值来生成待测信号的概率分布。 版权所有（C）2008，JPO＆INPIT
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公开(公告)号：JP2000307474A
公开(公告)日：2000-11-02
申请号：JP11251199
申请日：1999-04-20
Applicant: ADVANTEST CORP
Inventor： ARAI MICHIAKI , KAIZUMI KAZUHIRO
Abstract: PROBLEM TO BE SOLVED: To speedily measure and analyze an input signal in cycles shorter than the cycles of an external trigger signal when measuring the modulation precision of a CDMA(Code-Division Multiple Access) communication system. SOLUTION: The instrument is equipped with a PN offset measurement part 31 which correlates a pilot signal with an input over the entire range of the pilot signal and decides as a PN offset a group which is a set of the most correlative chips, a timer 24 which transmits a rigger having the same cycle as the pilot signal, and an analysis part 30 which analyzes modulation precision in synchronism with the trigger signal. The signal transmitted by the timer 24 has the same cycle with the pilot signal and the analysis part 30 examines correlations within a range of ±100 chips around the measured PN offset or previously inputted PN offset, so that the signal can be measured and analyzed with the same cycle with the pilot signal.
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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.
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