摘要:
An information system according to the invention comprises a record carrier and a playback apparatus. The record carrier has information marks along a track thereof and exhibits first variations caused by existence and nonexistence of the information marks along the track. The first variations represent an information signal recorded on said record carrier. The record carrier further exhibits second variations caused by variations associated with the information marks. The phase of the second variations is coupled to the phase of the first variations.
摘要:
In order to create a record carrier having a side-channel which cannot be copied with a channel-bit recorder, the record carrier (1) has a modulated spiral. By modulating one or more of the spiral parameters, like the channel bit length or the track pitch, a side-channel is created. If a record carrier having such a side-channel is copied using a channel-bit recorder, the information present in the side-channel is lost. The number of bits to be stored in the modulated spiral can be selected as desired; also the way in which the bits are present can be selected; the bits can e.g. can be stored in different bands (A,B,C,D) present on the record carrier, in which band the spiral parameter modulated can be kept constant.
摘要:
The invention relates to a method for generating a primary binary signal having a predetermined spectral shape in a predetermined frequency range, in particular having a notch in the power spectrum in a predetermined frequency range. In order to avoid crosstalk between a primary binary signal and a secondary binary signal it is proposed according to the invention that data-words are modulated into channel-words forming the channel bitstream of the primary binary signal and that the modulation of the data-words is chosen such that the predetermined spectral shape of the channel bitstream of the primary binary signal is achieved by using an evaluation criterion based on a spectral weight function the shape of which is tailored to the spectral extent of the channel bitstream of a secondary binary signal. The invention is in particular useful for generating a primary binary signal which is used in the lead-in area of an optical record carrier where a wobble is used in the secondary binary signal for storing a wobble key. The invention relates further to a device for generating the channel bitstream of a primary binary signal, to a primary binary signal and to a record carrier for storing such a binary signal.
摘要:
The invention relates to a method for generating a primary binary signal having a predetermined spectral shape in a predetermined frequency range, in particular having a notch in the power spectrum in a predetermined frequency range. In order to avoid crosstalk between a primary binary signal and a secondary binary signal it is proposed according to the invention that data-words are modulated into channel-words forming the channel bitstream of the primary binary signal and that the modulation of the data-words is chosen such that the predetermined spectral shape of the channel bitstream of the primary binary signal is achieved by using an evaluation criterion based on a spectral weight function the shape of which is tailored to the spectral extent of the channel bitstream of a secondary binary signal. The invention is in particular useful for generating a primary binary signal which is used in the lead-in area of an optical record carrier where a wobble is used in the secondary binary signal for storing a wobble key. The invention relates further to a device for generating the channel bitstream of a primary binary signal, to a primary binary signal and to a record carrier for storing such a binary signal.