Digital signal magnetic recording/reproducing apparatus using
multi-level QAM modulation and maximum likelihood decoding
    2.
    发明授权
    Digital signal magnetic recording/reproducing apparatus using multi-level QAM modulation and maximum likelihood decoding 失效
    使用多级QAM调制和最大似然解码的数字信号磁记录/再现装置

    公开(公告)号:US5095392A

    公开(公告)日:1992-03-10

    申请号:US302325

    申请日:1989-01-27

    摘要: A digital signal magnetic recording/reproducing apparatus converts a digital signal into multi-value digital signals and performs recording/reproducing of a multi-value quadrature amplitude-modulated signal. By using the multi-value quadrature amplitude modulation, it is possible to remove the DC component in the recording signal and improve the utilization efficiency of the recording frequency band. Further, using a system to memorize the frequency characteristic of the magnetic recording/reproducing unit and effect Viterbi decoding regarding the intersymbol interference caused by the frequency as a convolutional coding, it is possible to detect the level without necessitating frequency equalization. Accordingly, there arises no deterioration of the S/N ratio by frequency equalization. Furthermore, by providing an encoder for error control coding by increasing the number of multi-values and a corresponding decoder, the error rate can be improved against the deterioration of the S/N ratio. Further, by bias recording the multi-value quadrature amplitude modulated signal, non-linearity of the electromagnetic conversion system is relaxed, and deterioration of the S/N ratio by distortion is improved.

    摘要翻译: 数字信号磁记录/再现装置将数字信号转换为多值数字信号,并执行多值正交幅度调制信号的记录/再现。 通过使用多值正交幅度调制,可以去除记录信号中的DC分量并提高记录频带的利用效率。 此外,使用系统来存储磁记录/再现单元的频率特性,并且将由频率引起的码间干扰作为卷积编码进行维特比解码,可以在不需要频率均衡的情况下检测电平。 因此,通过频率均衡不会导致S / N比的恶化。 此外,通过提供用于通过增加多值的数量的差错控制编码的编码器和相应的解码器,可以相对于S / N比的劣化来提高错误率。 此外,通过偏置记录多值正交幅度调制信号,电磁转换系统的非线性松弛,并且通过失真降低S / N比。

    Digital signal magnetic recording/reproducing apparatus
    3.
    发明授权
    Digital signal magnetic recording/reproducing apparatus 失效
    数字信号磁记录/重放装置

    公开(公告)号:US5062007A

    公开(公告)日:1991-10-29

    申请号:US450997

    申请日:1989-12-15

    IPC分类号: G11B5/09 G11B20/10

    CPC分类号: G11B20/10

    摘要: A digital signal magnetic recording/reproducing apparatus converts a digital signal into a multi-value digital signal, followed by recording/reproducing the quadrature biphase modulated multi-value quadrature amplitude modulated signal. By using a multi-value quadrature amplitude modulation, a direct current component in the recorded signal can be eliminated, and the utilization efficiency of the recording frequency band of the digital signal magnetic recording/reproducing apparatus can be improved. Also, with respect to the amplitude non-linear characteristic which occurs in the magnetic recording/reproducing process, by providing a compensating circuit during the mapping before recording or after reproducing and demodulating, the deterioration of the S/N ratio of the reproduced and demodulated signal can be reduced to decrease the errors in the decoded data. Furthermore by bias-recording the multi-value quadrature amplitude modulation signal, the non-linearity of the electromagnetic conversion system is alleviated to decrease the deterioration of the S/N ratio due to distortion, thereby making the application of the modulation scheme more reliable.

    摘要翻译: 数字信号磁记录/再现装置将数字信号转换为多值数字信号,随后记录/再现正交双相调制多值正交幅度调制信号。 通过使用多值正交幅度调制,可以消除记录信号中的直流分量,并且可以提高数字信号磁记录/再现装置的记录频带的利用效率。 此外,关于在磁记录/再现处理中发生的振幅非线性特性,通过在记录之前或再现和解调之后的映射期间提供补偿电路,再现和解调的S / N比的恶化 可以减少信号以减少解码数据中的误差。 此外,通过对多值正交幅度调制信号进行偏置记录,可以减轻电磁转换系统的非线性,以减少由于失真引起的S / N比的恶化,从而使得调制方案的应用更可靠。

    Digital signal magnetic recording/reproducing apparatus
    4.
    发明授权
    Digital signal magnetic recording/reproducing apparatus 失效
    数字信号磁记录/重放装置

    公开(公告)号:US5119243A

    公开(公告)日:1992-06-02

    申请号:US452380

    申请日:1989-12-19

    摘要: A digital signal magnetic recording/reproducing apparatus modulates a digital signal with a carrier and performs recording/reproducing of the modulated signal. The carrier frequency is made equal to the clock frequency multiplied by a factor (N/M), where N and M are integers. The carrier and clock are reproduced using only one phase locked loop. When the carrier-modulated signal is recorded/reproduced using a magnetic recording medium, the phase of the modulated signal is shifted relative to the phase of the carrier. Shifting the clock phase before using the clock for decoding the demodulated signal prevents a degradation of error rate. By periodically inserting a clock phase reference signal in the recording signal, accuracy of adjustment of clock phase is improved.

    摘要翻译: 数字信号磁记录/再现装置用载波调制数字信号并执行调制信号的记录/再现。 载波频率等于时钟频率乘以因子(N / M),其中N和M是整数。 载波和时钟仅使用一个锁相环进行复制。 当使用磁记录介质记录/再现载波调制信号时,调制信号的相位相对于载波的相位移位。 在使用时钟解码解调信号之前切换时钟相位可防止错误率的降低。 通过在记录信号中周期性地插入时钟相位参考信号,提高了时钟相位的调整精度。

    Digital signal magnetic recording/reproducing apparatus
    5.
    发明授权
    Digital signal magnetic recording/reproducing apparatus 失效
    数字信号磁记录/重放装置

    公开(公告)号:US4979052A

    公开(公告)日:1990-12-18

    申请号:US251094

    申请日:1988-09-29

    IPC分类号: G11B5/09 G11B20/10

    CPC分类号: G11B20/10 G11B5/09

    摘要: A digital signal magnetic recording/reproducing apparatus converts a digital signal into a multi-value quadrature amplitude modulated signal, and records and reproduces the multi-value quadrature amplitude modulated signal. By using the multi-value quadrture amplitude modulation, any DC component in the recording signal is removed and utilization efficiency of the recording frequency band can be improved. By bias recording of the multi-value quadrature amplitude modulated signal, non-linearity of the electromagnetic of conversion system is reduced, and deterioration of SN ratio due to distortion is improved.

    摘要翻译: 数字信号磁记录/再现装置将数字信号转换为多值正交幅度调制信号,并记录和再现多值正交幅度调制信号。 通过使用多值二次振幅调制,去除记录信号中的任何DC分量,并且可以提高记录频带的利用效率。 通过多值正交幅度调制信号的偏置记录,转换系统的电磁场的非线性减小,并且由于失真引起的SN比的恶化得到改善。

    Video signals recorder and player including interframe calculating means
    7.
    发明授权
    Video signals recorder and player including interframe calculating means 失效
    视频信号记录器和播放器包括帧间计算装置

    公开(公告)号:US5418620A

    公开(公告)日:1995-05-23

    申请号:US983758

    申请日:1992-12-01

    摘要: When a standard TV signal of digital format is a first video signal and another digitized TV signal having a bandwidth wider than that of the first video signal is a second video signal, every two frames of the second video signal are calculated to produce a pixel value sum of the two frames and a pixel value difference between the same and either a resultant interframe calculated output or the first video signal is compressed through two-dimensional orthogonal transformation for ease of storage.

    摘要翻译: 当数字格式的标准TV信号是第一视频信号,并且具有比第一视频信号宽的带宽的另一数字化TV信号是第二视频信号时,计算第二视频信号的每两帧以产生像素值 通过二维正交变换来压​​缩两帧的和,并且通过二维正交变换来压​​缩相位和所得到的帧间计算输出或第一视频信号之间的像素值差,便于存储。

    Video signal encoding and decoding apparatus
    8.
    发明授权
    Video signal encoding and decoding apparatus 失效
    视讯信号编解码装置

    公开(公告)号:US5367334A

    公开(公告)日:1994-11-22

    申请号:US882927

    申请日:1992-05-14

    摘要: An encoding and decoding apparatus for a video signal and a high-definition television signal is disclosed. For the picture A having the horizontal to vertical screen frame ratio of 4:3, the picture B having the horizontal to vertical screen frame ratio of 16:9 and the picture C having the horizontal to vertical screen frame ratio of 16:9 and having a larger number of vertical pixels than that of the picture A and picture B, the apparatus limits the band of the picture C to obtain the picture D having the same numbers of horizontal and vertical pixels respectively as those of the picture B, and high-efficiency encodes the picture A, picture B or picture D in the same method. The apparatus obtains the additional picture E which is a difference between the picture D and the picture C, or a difference between the picture D' which is a result of decoding a signal that has been obtained by high-efficiency encoding the picture D and the picture C, and then high-efficiency encodes the additional picture E obtained.

    摘要翻译: 公开了一种用于视频信号和高清晰度电视信号的编码和解码装置。 对于水平至垂直屏幕帧比为4:3的图像A,图像B的水平垂直屏幕帧比为16:9,图像C的水平垂直屏幕帧比为16:9,并具有 垂直像素数量大于图像A和图像B的垂直像素数量,该装置限制图像C的频带以获得具有与图像B相同数量的水平和垂直像素数量的图像D, 以相同的方法对图像A,图像B或图像D进行高效编码。 该装置获得作为图像D和图像C之间的差的附加图像E,或作为通过对图像D进行高效编码获得的信号的解码结果的图像D'与 图片C,然后对所获得的附加图片E进行高效编码。

    Receiver
    9.
    发明授权
    Receiver 失效
    接收器

    公开(公告)号:US06577349B1

    公开(公告)日:2003-06-10

    申请号:US09027389

    申请日:1998-02-20

    IPC分类号: H04N546

    CPC分类号: H04N7/012 H04N5/46

    摘要: A receiver to receive a mixture of progressive and interlace video broadcast signals without being conscious of switching between the broadcasting systems. The receiver receives the mixed video broadcast signals having different formats, converts received video signals to video signals having a different signal format from the signal format of the received video signals. The receiver simultaneously outputs the received video signals and the converted video signals. This allows the user to be unaware of any switching when the video input changes between the different broadcasting systems, by connecting a television set to either the interlace scanning system output or the progressive scanning system output of the receiver.

    摘要翻译: 接收器,用于接收渐进和隔行扫描视频广播信号的混合,而不意识到在广播系统之间切换。 接收机接收具有不同格式的混合视频广播信号,将接收到的视频信号转换为具有不同信号格式的视频信号与接收到的视频信号的信号格式。 接收机同时输出接收到的视频信号和转换的视频信号。 这允许用户通过将电视机连接到接收机的隔行扫描系统输出或逐行扫描系统输出而在视频输入在不同的广播系统之间变化时,不知道任何切换。