Kabushiki Kaisha Toshiba

Nec Corporation

Hiroharu Sato

Chosaku Noda

Kazuo Watabe

Hideaki Ohsawa

Hideo Ando

Yuji Nagai

Akihito Ogawa

Tadashi Kojima

Hisashi Yamada

Naomasa Nakamura

Naoki Morishita

Yutaka Yamanaka

Kazuto Kuroda

Toshihiro Sugaya

Toshihiko Kaneshige

Toshiaki Iwanaga

Nobuhisa Yoshida

Kinji Kayanuma

Nobumasa Naito

According to one embodiment, a first encoder encodes main information, a second encoder encodes sub-information, a first modulator modulates a carrier based on an output of the first encoder, a duplicating module duplicates an output of the second encoder to generate encoded sub-information units, and a second modulator amplitude-modulates an output of the first modulator based on the encoded sub-information units. The second modulator amplitude-modulates with &#x3c3;/(&#x3bc;&#xd7;(2)) being 0.4 or less, wherein a noise power of a transmission path or a storage medium is &#x3c3;, a number of the encoded sub-information units is N, signal levels after amplitude modulation, which correspond to bitand bitof the encoded sub-information units, are A and B, and a level difference A&#x2212;B is &#x3bc;.

Signal processing system and information storage medium

A recording data string is composed of a plurality of synchronous frames each of which has synchronous data and coding data. Data items in the coding data contributed to creation of the same column of the error correction code are arranged at regular intervals of E in the recording data string. A data segment length L is obtained by adding an additional synchronous frame to the recording data string. Wherein, a physical segment length A satisfies the equation L=mA, m is a natural number. And A is set indivisible by E.

Optical disk medium and optical disk recording and reproducing apparatus

User data recording areas and intermediate areas are alternately arranged on a disk. The intermediate area records at least information for synchronization.

Optical recording medium, information reproduction apparatus, and information recording/reproduction apparatus

As pit patterns a pattern A and a pattern B are prepared. The adjacent tracks are made to have different embossed pit patterns.

Recording medium, signal recording method and apparatus and signal reproducing apparatus

Growing community of inventors

Tokyo, Japan

Hiroharu Sato