Read channel apparatus for asynchronous sampling and synchronous equalization
    1.
    发明授权
    Read channel apparatus for asynchronous sampling and synchronous equalization 有权
    用于异步采样和同步均衡的通道设备

    公开(公告)号:US07394608B2

    公开(公告)日:2008-07-01

    申请号:US11213127

    申请日:2005-08-26

    IPC分类号: G11B5/09

    摘要: A read channel and method using that read channel are disclosed. The read channel comprises an analog to digital converter which asynchronously samples at a fixed rate an analog signal formed by reading a data track, where that data track was written to a data storage medium at a symbol rate and an interpolator interconnected with the analog to digital converter. The read channel further comprises a fractionally-spaced equalizer, where the interpolator provides an interpolated signal to the fractionally-spaced equalizer at an interpolation rate, where that interpolation rate is greater than the symbol rate. The fractionally-spaced equalizer forms a synchronous equalized signal. The read channel further comprises a gain control module interconnected with the fractionally-spaced equalizer, and a sequence detector interconnected with the gain control module.

    摘要翻译: 公开了使用该读通道的读通道和方法。 读通道包括模数转换器,其以固定速率异步采样通过读取数据轨道形成的模拟信号,其中数据轨道以符号速率写入数据存储介质,并且与模数转换器互连的内插器 转换器。 读通道还包括分数间隔的均衡器,其中内插器以内插速率向分数间隔的均衡器提供内插信号,其中该内插速率大于符号率。 分数间隔均衡器形成同步均衡信号。 读通道还包括与分数间隔均衡器互连的增益控制模块,以及与增益控制模块互连的序列检测器。

    Read channel apparatus for asynchronous sampling and synchronous equalization
    2.
    发明授权
    Read channel apparatus for asynchronous sampling and synchronous equalization 有权
    用于异步采样和同步均衡的通道设备

    公开(公告)号:US07684139B2

    公开(公告)日:2010-03-23

    申请号:US12166136

    申请日:2008-07-01

    IPC分类号: G11B5/035

    摘要: A read channel and method using that read channel are disclosed. The read channel comprises an analog to digital converter which asynchronously samples at a fixed rate an analog signal formed by reading a data track, where that data track was written to a data storage medium at a symbol rate and an interpolator interconnected with the analog to digital converter. The read channel further comprises a fractionally-spaced equalizer, where the interpolator provides an interpolated signal to the fractionally-spaced equalizer at an interpolation rate, where that interpolation rate is greater than the symbol rate. The fractionally-spaced equalizer forms a synchronous equalized signal. The read channel further comprises a gain control module interconnected with the fractionally-spaced equalizer, and a sequence detector interconnected with the gain control module.

    摘要翻译: 公开了使用该读通道的读通道和方法。 读通道包括模数转换器,其以固定速率异步采样通过读取数据轨道形成的模拟信号,其中数据轨道以符号速率写入数据存储介质,并且与模数转换器互连的内插器 转换器。 读通道还包括分数间隔的均衡器,其中内插器以内插速率向分数间隔的均衡器提供内插信号,其中该内插速率大于符号率。 分数间隔均衡器形成同步均衡信号。 读通道还包括与分数间隔均衡器互连的增益控制模块,以及与增益控制模块互连的序列检测器。

    Reading from record medium in either an inverted or non-inverted
signal-processing mode
    8.
    发明授权
    Reading from record medium in either an inverted or non-inverted signal-processing mode 失效
    以倒置或非反相信号处理模式从记录介质读取

    公开(公告)号:US5568465A

    公开(公告)日:1996-10-22

    申请号:US416399

    申请日:1995-04-07

    CPC分类号: G11B20/10 G11B19/04 G11B7/005

    摘要: In a write-once read-many (WORM) optical disk device recorded unipolar pulse signals having a high lineal recorded densities are read back using an inverted analog signal processing channel that processes the read back signal after polarity inversion of the read back signal. Some fields in each sector of an optical disk are recorded at a specific maximal mark density pattern. Read back of such fields is signal processed using non-inverted read back analog signal processing, i.e. the read back unipolar pulse signal is processed without polarity inversion. In the non-inverted read back, automatic gain control of the read signal is turned off such that amplification of the read back signal is at a constant gain. Also during non-inverted read back, low read back signal amplitude results in degating the read back output. These signal processing techniques produce a pulse stream which can be further processed by a circuit which qualifies acceptable time intervals and a counter to robustly determine whether the field has been written. Digital signal processing provides signal detection with or without read back signal inversion while maintaining robust flag signal detection. Digital automatic gain control is effected to an acceptable range of signal amplitudes either continuously, on a sector basis, detected error basis or session basis.

    摘要翻译: 在一次写入多次(WORM)光盘装置中,记录具有高线性记录密度的单极性脉冲信号,使用反相模拟信号处理通道读回,该反相模拟信号处理通道在读回信号的极性反转之后处理回读信号。 以特定的最大标记密度图案记录光盘的每个扇区中的一些场。 使用非反相回读模拟信号处理对这些场的读回信号进行信号处理,即回读单极性脉冲信号在无极性反转的情况下进行处理。 在非反相读取中,读取信号的自动增益控制被关闭,使得读回信号的放大处于恒定的增益。 此外,在非反相读回时,低回读信号幅度导致读回输出脱磁。 这些信号处理技术产生脉冲流,该脉冲流可以由限定可接受的时间间隔的电路进一步处理,并且计数器可鲁棒地确定该场是否被写入。 数字信号处理提供具有或不具有回读信号反转的信号检测,同时保持鲁棒的标志信号检测。 数字自动增益控制可以连续地,以扇区为基础,以检测到的误差基础或会话为基础进行信号幅度的可接受范围。

    Apparatus and method to read information from a tape storage medium
    9.
    发明授权
    Apparatus and method to read information from a tape storage medium 有权
    从磁带存储介质读取信息的装置和方法

    公开(公告)号:US07019922B2

    公开(公告)日:2006-03-28

    申请号:US10426403

    申请日:2003-04-29

    IPC分类号: G11B20/10 G11B5/035

    摘要: A method to read information from a tape storage medium, where that tape includes a calibration region and a data region. The method uses a read channel having a first detection mode and a second detection mode. The method initializes the first detection mode and forms a calibration waveform comprising information read from the calibration region using the first detection mode. The method then defines a plurality of bit cell boundaries, initializes the second detection mode, and reads information from the data region using the second detection mode.

    摘要翻译: 从磁带存储介质读取信息的方法,其中该磁带包括校准区域和数据区域。 该方法使用具有第一检测模式和第二检测模式的读取通道。 该方法初始化第一检测模式并且形成包括使用第一检测模式从校准区域读取的信息的校准波形。 该方法然后定义多个位单元边界,初始化第二检测模式,并使用第二检测模式从数据区读取信息。

    Data-transition threshold following in optical recording

    公开(公告)号:US5629914A

    公开(公告)日:1997-05-13

    申请号:US407125

    申请日:1995-03-20

    IPC分类号: G11B7/0037 G11B20/10 G11B7/00

    摘要: In a pulse width modulated read signal channel for an optical disk drive, a data-transition threshold is maintained for data detection by a threshold tracking circuit that estimates the amplitude centerline data-transition threshold from the most recent maximum and minimum values of the read signal waveform. To improve the accuracy of the response of the centerline estimator, the threshold is increased or decreased based on the phase error at each read signal transition through the data-transition threshold. In addition, defects in the optical recording media are detected, and a defect present signal is used to inhibit the transition phase error input to the centerline estimator. This prevents the estimator from moving the threshold to an incorrect stable level. In addition, the defect present signal boosts the error feedback in the centerline estimator. The estimator then more quickly follows the read signal waveform. As a result, the estimator reacquires the centerline of the waveform after the read head moves past the defect without retriggering the defect detection circuit.