US5559920A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dispersion compensation in optical fiber communications
Assignee: Nokia of America Corp
•
Filing: 1995-03-01
•
Granted: 1996-09-24
•
Expires: 2015-03-01
Abstract
Abstract Critical placement and lengths of dispersion-compensating fiber maximize capacity in upgraded in-ground optical fiber communication systems. Higher per-channel bit rates in single-channel systems and in WDM systems are permitted.
Inventors
- 👤 Andrew R. Chraplyvy
- 👤 Fabrizio Forghieri
- 👤 Alan H. Gnauck
- 👤 Robert W. Tkach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:11
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/25; H04B10/2507; H04B10/2513; H04B10/2525; H04B10/25253
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
153 words
Optical fiber communication system for operation at a system wavelength, including a transmitter, a receiver, and a transmission line comprising successive amplified fiber spans of alternating sign of dispersion; in which the transmission line includes an initial fiber span following the transmitter, a terminal span before the receiver, and at least one intermediate span; in which length and dispersion magnitude of the terminal span is such as to compensate dispersion for a signal introduced into the receiver characterized in that the transmission line includes at least one pair of successive spans in addition to the terminal span, such that residual dispersion of the line is at least ±50 ps/nm at the commencement of the pair, and in that members of the pair are of lengths and dispersion magnitudes such that residual dispersion at their termini is at least ±50 ps/nm, whereby residual dispersion of the transmission line is compensated at the system wavelength.
Claim 2
Dependent Claim
153 words
Optical fiber communication system for operation at a system wavelength, including a transmitter, a receiver, and a transmission line comprising successive amplified fiber spans of alternating sign of dispersion; in which the transmission line includes an initial fiber span following the transmitter, a terminal span before the receiver, and at least one intermediate span; in which length and dispersion magnitude of the terminal span is such as to compensate dispersion for a signal introduced into the receiver characterized in that the transmission line includes at least one pair of successive spans in addition to the terminal span, such that residual dispersion of the line is at least ±50 ps/nm at the commencement of the pair, and in that members of the pair are of lengths and dispersion magnitudes such that residual dispersion at their termini is at least ±50 ps/nm, whereby residual dispersion of the transmission line is compensated at the system wavelength.
Claim 3
Dependent Claim
10 words
System of claim 1 including at least three intermediate spans.
Claim 4
Dependent Claim
22 words
System of claim 2 in which fiber of alternating spans is dispersion-compensating fiber of dispersion at least twice that of intervening spans.
Claim 5
Dependent Claim
14 words
System of claim 1 in which members of the pair consist of transmission fiber.
Claim 6
Dependent Claim
22 words
System of claim 4 in which members of the pair have absolute values of dispersion of from 1.5 ps/nm-km to 4.0 ps/nm-km.
Claim 7
Dependent Claim
23 words
System of claim 1 for operation at a nominal signal wavelength of nm and at a per-channel bit-rate of at least 10 Gbit/sec.
Claim 8
Dependent Claim
15 words
System of claim 6 for operation at a per-channel bit-rate of at least 20 Gbit/sec.
Claim 9
Dependent Claim
17 words
System of claim 1 with provision for WDM operation comprising a channel multiplexer and a channel demultiplexer.
Claim 10
Dependent Claim
79 words
Communication method for operation over a dispersion-compensated silica-based multiple span optical fiber communication transmission line including the steps of modulation and amplification characterized in that the line includes successive spans of alternating sign of dispersion with residual dispersion at the end of each span of at least ±50 ps/nm, whereby residual dispersion is compensated, in which effective fiber core size and signal power introduced into each span result in a power density of at least 0.05 mw/μm 2 .
Claim 11
Dependent Claim
79 words
Communication method for operation over a dispersion-compensated silica-based multiple span optical fiber communication transmission line including the steps of modulation and amplification characterized in that the line includes successive spans of alternating sign of dispersion with residual dispersion at the end of each span of at least ±50 ps/nm, whereby residual dispersion is compensated, in which effective fiber core size and signal power introduced into each span result in a power density of at least 0.05 mw/μm 2 .
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-09-24 | 2000-03-25 | 2000-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-09-24 | 2004-03-25 | 2004-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-09-24 | 2008-03-25 | 2008-09-24 | $7700.00 | Window Closed / Lapsed |