发明名称 |
KOHÄRENTES OPTISCHES SYSTEM MIT MEHREREN EBENEN. |
摘要 |
PCT No. PCT/IT91/00036 Sec. 371 Date Nov. 9, 1992 Sec. 102(e) Date Nov. 9, 1992 PCT Filed May 6, 1991 PCT Pub. No. WO91/18455 PCT Pub. Date Nov. 28, 1991.A multilevel coherent optical system, including a heterodyne transmitter and receiver, in which a multilevel signal with a coherent optical carrier is provided by modulating the phase and the polarization of the electromagnetic field propagating through a single-mode optical fiber. The transmitter comprises a coherent light source providing the optical carrier, a phase modulator modulating the phase of the carrier, a polarization modulator, and a modulation signal generator providing control signals to the phase modulator and the polarization modulator. The receiver comprises a first stage carrying out the heterodyne detection of the phase component and the phase quadrature component of the polarization of the signal received through an optical fiber, a second stage demodulating the received signal to provide the multilevel signal, and a processing circuit comparing the received multilevel signal with predetermined reference signals. Such a system exploits the four degrees of freedom of the electromagnetic field propagating through the optical fiber so as to more closely approach the theoretical Shannon limit compared with conventional systems. |
申请公布号 |
DE69104199(D1) |
申请公布日期 |
1994.10.27 |
申请号 |
DE1991604199 |
申请日期 |
1991.05.06 |
申请人 |
FONDAZIONE UGO BORDONI, ROM/ROMA, IT |
发明人 |
BETTI, SILVELLO, I-00158 ROMA, IT;CURTI, FRANCO, I-00149 ROMA, IT;DE MARCHIS, GIANCARLO, I-00159 ROMA, IT;IANNONE, EUGENIO, I-00165 ROMA, IT |
分类号 |
H04B10/135;H04B10/142;H04B10/148;H04L27/32;(IPC1-7):H04B10/12;H04B10/14 |
主分类号 |
H04B10/135 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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