公开(公告)号：US06304200B1

公开(公告)日：2001-10-16

申请号：US09382097

申请日：1999-08-24

申请人： Toshihiko Masuda

发明人： Toshihiko Masuda

IPC分类号： H03M166

CPC分类号： H03M3/398 ,  H03M1/822 ,  H03M3/506

摘要： A digital/analog conversion apparatus for converting an input digital signal into an analog signal. The digital/analog conversion apparatus is adapted for reproduction of a disk having layers in which signals sampled with different frequencies are recorded. The digital/analog conversion apparatus includes a circuit for converting digital signals read out from the layers of the disk into N-bit signals, and a PWM conversion circuit into which the N-bit signals are input. An analog circuit provided in a stage following the PWM conversion circuit is used commonly for the different signals reproduced from the disk.

摘要翻译： 一种用于将输入数字信号转换为模拟信号的数字/模拟转换装置。 数字/模拟转换装置适于再现具有以不同频率采样的信号被记录的层的盘。 数字/模拟转换装置包括用于将从盘的层读出的数字信号转换为N位信号的电路，以及输入N位信号的PWM转换电路。 在PWM转换电路之后的级中提供的模拟电路通常用于从盘再现的不同信号。

公开(公告)号：US6075473A

公开(公告)日：2000-06-13

申请号：US40368

申请日：1998-03-18

申请人： Toshihiko Masuda

发明人： Toshihiko Masuda

IPC分类号： H03M1/82 ,  H03K17/041 ,  H03K17/62 ,  H03M1/08 ,  H03M1/66 ,  H03M1/74 ,  H03M3/02 ,  H03M1/06 ,  H03K17/16 ,  H03K17/30

CPC分类号： H03M1/0872 ,  H03K17/04113 ,  H03K17/6264 ,  H03M1/747

摘要： A D/A converter of a multibit type has improved performance by reducing dispersion of the electric currents of plural electric current sources as much as possible, in which the D/A converter has a constant electric current source (10) constructed by 2.sup.N (N=2, 3, - - - and here, N=16) constant electric current sources having constant electric current values equal to each other; selectors (7, 8) for selecting Di constant electric current sources according to input data Di {here, Di=0, 1, 2, 3, - - - , (2.sup.N -1)} having N-bits in input word length so as to use these 2.sup.N constant electric current sources one by one until a sum of values of one input data or continuous plural input data among these 2.sup.N constant electric current sources exceeds 2.sup.N ; and an electric current adding means (9) for adding each of the constant electric currents from the Di constant electric current sources selected by the selectors to each other.

摘要翻译： 多位型AD / A转换器通过尽可能减少多个电流源的电流的分散而提高了性能，其中D / A转换器具有由2N构成的恒定电流源（10）（N = 2，3， - - - ，这里，N = 16）恒定电流源，其电流值彼此相等; 用于根据输入字长为N位的输入数据Di {这里，Di = 0,1,2,3，...，（2N-1）}选择Di恒定电流源的选择器（7,8） 一直使用这2N个恒定电流源，直到这2N个恒定电流源中的一个输入数据或连续的多个输入数据的值的和超过2N; 以及用于将由选择器选择的Di恒定电流源中的每个恒定电流彼此相加的电流添加装置（9）。

公开(公告)号：US5457255A

公开(公告)日：1995-10-10

申请号：US248530

申请日：1994-05-24

申请人： Fumio Kumata ,  Toshihiko Masuda ,  Iwao Ueda

发明人： Fumio Kumata ,  Toshihiko Masuda ,  Iwao Ueda

IPC分类号： B01J29/04 ,  B01J29/74 ,  B01J29/88 ,  C07B61/00 ,  C07C4/18 ,  C07C15/02 ,  C07C4/12

CPC分类号： C07C4/18 ,  C07C2529/44

摘要： A catalyst for hydrogenolytic dealkylation comprising rhodium on a crystalline metallo-silicate carrier and a process for hydrogenolytically dealkylating a hydrocarbon mixture mainly comprising alkyl aromatic hydrocarbons in the presence of such a catalyst are disclosed. The catalyst exhibits catalytic activity at low temperatures and high reaction selectivity and has a prolonged duration.

摘要翻译： 公开了一种用于在结晶金属 - 硅酸盐载体上包含铑的氢解脱烷基化催化剂和在这种催化剂存在下主要包含烷基芳族烃的烃混合物氢解脱烷基化的方法。 该催化剂在低温下表现出催化活性，反应选择性高，持续时间长。

公开(公告)号：US5148168A

公开(公告)日：1992-09-15

申请号：US693373

申请日：1991-04-30

申请人： Toshihiko Masuda ,  Masaaki Ueki

发明人： Toshihiko Masuda ,  Masaaki Ueki

IPC分类号： H03M1/08 ,  H03M1/82

CPC分类号： H03M1/822

摘要： A digital-to-analog converter utilizing a PWM system for converting input digital data to PWM signals and finally to an analog signal divides the sampling period of the input digital data into an even number of sampling periods and produces PWM signals with equal pulse widths corresponding to the input digital data each divided sampling period, whereby a simple structure is provided to reduce harmonic distortion and obtain a high quality analog signal.

公开(公告)号：US5073778A

公开(公告)日：1991-12-17

申请号：US428958

申请日：1989-10-30

申请人： Masaaki Ueki ,  Nobuyuki Yasuda ,  Toshihiko Masuda

发明人： Masaaki Ueki ,  Nobuyuki Yasuda ,  Toshihiko Masuda

IPC分类号： H03M1/08 ,  H03H17/02 ,  H04B14/04

CPC分类号： H04B14/046

摘要： A signal processing apparatus reduces the quantization noise by using so-called noise shaping circuits. The input signal may be audio or video signals. One of the noise shaping circuits is supplied with a signal which is the relative addition of the input signal and a dither while the other noise shaping circuit is supplied with a signal which is the relative subtraction of the input signal and the dither. The signal components of the outputs of the noise shaping circuits are effectively combined to cancel the dither components to produce an output with an improved S/N ratio. A plurality of such signal processing apparatus may be arranged in parallel, in which case different dithers are used in the respective signal processing apparatus and the outputs of the respective signal processing apparatus are combined to further improve the S/N ratio.

摘要翻译： 信号处理装置通过使用所谓的噪声整形电路来降低量化噪声。 输入信号可以是音频或视频信号。 其中一个噪声整形电路被提供有信号，该信号是输入信号的相对相加和抖动，而另一个噪声整形电路被提供有作为输入信号和抖动的相对减法的信号。 噪声整形电路的输出的信号分量被有效地组合以抵消抖动分量以产生具有改善的S / N比的输出。 可以并行地布置多个这样的信号处理装置，在这种情况下，在各个信号处理装置中使用不同的抖动，并且组合各个信号处理装置的输出以进一步提高S / N比。

公开(公告)号：US5021788A

公开(公告)日：1991-06-04

申请号：US479163

申请日：1990-02-13

申请人： Massaaki Ueki ,  Toshihiko Masuda ,  Takashi Kanai

发明人： Massaaki Ueki ,  Toshihiko Masuda ,  Takashi Kanai

IPC分类号： H03M1/82 ,  H03M1/06 ,  H03M1/08 ,  H03M3/04

CPC分类号： H03M1/0682 ,  H03M1/0614 ,  H03M1/822 ,  H03M3/506

摘要： A PWM digital-to-analog converter is disclosed in which a value representing a differential between a first pulse width modulated waveform based upon input digital data and a second pulse width modulated waveform representing a 2's complement version of the input digital data is produced by a differential amplifier and high frequency components thereof are attenuated to produce an analog output signal and with an improved distortion factor.