公开(公告)号：US5825735A

公开(公告)日：1998-10-20

申请号：US935321

申请日：1997-09-22

申请人： Ayataka Nishio ,  Yasuhiro Ogura

发明人： Ayataka Nishio ,  Yasuhiro Ogura

IPC分类号： G11B7/0037 ,  G11B19/12 ,  G11B19/26 ,  G11B20/10 ,  G11B20/24 ,  G11B3/90

CPC分类号： G11B20/10037 ,  G11B19/12 ,  G11B19/26 ,  G11B20/10009 ,  G11B20/10527 ,  G11B20/24 ,  G11B7/0037

摘要： A second generation CD provides improved sound quality over that provided by a first generation CD while remaining compatible with it has a higher sampling rate and has a data format of 1-bit .DELTA..SIGMA. modulation. The higher sampling frequency is an integer multiple of the standard sampling frequency of 44.1 kHz used in the first generation CD to thereby simplify the clock signal generation circuitry. The recording system uses decimation filters to lower the sampling frequency of the 1-bit .DELTA..SIGMA. modulation signal so that the same signal can be used to manufacture both a first generation CD and a second generation CD. The playback apparatus is compatible and the kind of disk is determined based on the table of contents information, so that the appropriate clock signals can be provided to the decoders. In the case of the first generation CD being played back, the data is converted by an oversampling filter and a .DELTA..SIGMA. modulator before being digital to analog converted.

摘要翻译： 第二代CD提供比第一代CD提供的更好的声音质量，同时与其兼容，具有较高的采样率并具有1位DELTA SIGMA调制的数据格式。 较高的采样频率是第一代CD中使用的标准采样频率为44.1 kHz的整数倍，从而简化了时钟信号产生电路。 记录系统使用抽取滤波器来降低1位DELTA SIGMA调制信号的采样频率，使得可以使用相同的信号来制造第一代CD和第二代CD。 播放装置是兼容的，并且基于目录信息确定盘的种类，从而可以向解码器提供适当的时钟信号。 在第一代CD被播放的情况下，在进行数字到模拟转换之前，数据由过采样滤波器和DELTA SIGMA调制器转换。

公开(公告)号：US5177699A

公开(公告)日：1993-01-05

申请号：US838316

申请日：1992-02-20

申请人： Ayataka Nishio

发明人： Ayataka Nishio

IPC分类号： H03M1/12 ,  H03H17/02 ,  H03M3/02

CPC分类号： H03M3/35 ,  H03M3/462

摘要： In an apparatus for converting an analogue signal to a digital signal, the analogue signal is sampled by a sampling pulse having a multiple frequency (N fs, N is an integer) of a nominal sampling frequency (fs) so as to generate an M bit (M is an integer) digital signal, first and second decimate filter circuits receive the M bit digital signal and provide a multiple M (P M, P is an integer) bit digital signal having the nominal sampling frequency fs, the first decimate filter circuit receives the M bit digital signal at upper M input terminals and the second decimate filter circuit receives the M bit digital signal by bit shift down, and the multiple M bit digital signals output from the first and second decimate filter circuits are added to provide a digital output signal. Therefore, when an analogue audio signal is converted into a digital audio signal, the disturbance of lower bit data by higher bit data can be reduced so that the quality of a reproduced sound can be improved.

摘要翻译： 在用于将模拟信号转换为数字信号的装置中，通过具有标称采样频率（fs）的多频（N fs，N是整数）的采样脉冲对模拟信号进行采样，以产生M位 （M是整数）数字信号，第一和第二抽取滤波器电路接收M位数字信号，并提供具有标称采样频率fs的多M（PM，P是整数）位数字信号，第一抽取滤波电路接收 上M个输入端的M位数字信号和第二抽取滤波电路通过位移向下接收M位数字信号，并且相加从第一和第二抽取滤波器电路输出的多个M位数字信号以提供数字输出 信号。 因此，当模拟音频信号被转换为数字音频信号时，可以减少较高位数据对较低位数据的干扰，从而可以提高再生声音的质量。