发明名称 |
Optical transmission system. |
摘要 |
<p>A broad spectrum optical carrier from a source (l) is divided over at least two paths (4), and the carrier in at least one path (4) is modulated (M1-4) in accordance with information (I1-4). The paths are recombined (6) with delay multiplexing (t1-4). At a distribution point (7), the recombined paths (6) are divided and the modulated carrrier in at least one of the paths is combined in heterodyne detection (at D1-4) with a local oscillator signal (via path 5) having a frequency shifted with respect to the carrier. The local oscillator signal is delayed prior to combination by a delay (t1'-4') corresponding to a delay of the delay multiplexing.</p> |
申请公布号 |
EP0251748(A1) |
申请公布日期 |
1988.01.07 |
申请号 |
EP19870305737 |
申请日期 |
1987.06.26 |
申请人 |
BRITISH TELECOMMUNICATIONS PUBLIC LIMITED COMPANY |
发明人 |
SMITH, DAVID WILLIAM |
分类号 |
H04B10/04;H04B1/69;H04B10/06;H04B10/142;H04B10/152;H04B10/64;H04J14/00;H04J14/08 |
主分类号 |
H04B10/04 |
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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