The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 03, 2006
Filed:
Jun. 26, 2002
Yutaka Miyamoto, Yokohama, JP;
Akira Hirano, Yokohama, JP;
Shoichiro Kuwahara, Yokosuka, JP;
Masahito Tomizawa, Yokosuka, JP;
Yutaka Miyamoto, Yokohama, JP;
Akira Hirano, Yokohama, JP;
Shoichiro Kuwahara, Yokosuka, JP;
Masahito Tomizawa, Yokosuka, JP;
Nippon Telegraph and Telephone Coproration, Tokyo, JP;
Abstract
The present invention suppresses to a minimum the degradation of the transmission quality caused by chromatic dispersion characteristic of an optical transmission medium, and the interplay between the chromatic dispersion and non-linear optical effects in dense WDM transport systems. A baseband input data signal is pre-coded in advance by a pre-coding unit, phase modulation is carried out using a pre-coded signal by the optical phase modulating unit, and the phase modulated optical signal is converted to an RZ intensity modulated signal by the optical filter unit that performs phase-shift-keying to amplitude-shift-keying conversion. For example, an optical phase modulating unit generates an encoded DPSK phase modulated signal using a differential phase shirt keying (DPSK) format, and a phase modulated signal is converted to an RZ intensity modulated signal by the optical filter unit disposed downstream of the optical phase modulating unit.