Patent US4593237A successfully refreshed from Google Patents.
Patent US5680490A successfully refreshed from Google Patents.
US5680490A
Expired / Lapsed
US
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Comb splitting system and method for a multichannel optical fiber communication network
Assignee: Qualcomm Inc
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Filing: 1995-09-08
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Granted: 1997-10-21
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Expires: 2015-09-08
Abstract
Abstract A comb splitting system demultiplexes and/or multiplexes a plurality of optical signal channels at various wavelengths. The comb splitting system has at least two interconnected successive stages of wavelength division multiplexers (WDMs). A WDM of a first stage communicates bands of channels to respective WDMs of the second stage via suitable optical paths. Each of the bands has a plurality of the individual channels that are separated by at least one other of the channels. Each second stage WDM, which is allocated to a particular band, is interconnected to optical paths, each for carrying one or more individual channels. Furthermore, in accordance with a significant feature of the present invention, the bandpasses and bandpass periodicity (free spectral range) associated with the first stage WDM are smaller than the bandpasses and bandpass periodicity associated with the second stage WDMs. The foregoing feature has numerous advantages. The second stage WDMs are less expensive and physically smaller than the first stage WDM. Crosstalk between channels is reduced. The alignment of the WDM passbands with the wavelengths of the transmitters/receivers in a central office is simplified. Later stages of WDMs can tolerate larger fabrication errors, do not require flat passbands and birefringence compensation, and can tolerate full environmental temperature variations without feedback control in the central office.
Inventors
- 👤 Leonard G. Cohen
- 👤 Yuan P. Li
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 03:37
CPC Classifications
H; H04; H04J; H04J14/00; H04J14/02; H04J14/03; H04J14/0307
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
101 words
A comb splitting system for demultiplexing an optical signal into a plurality of individual channels at various wavelengths, comprising: first stage wavelength division multiplexer (WDM) for receiving said optical signal having said plurality of individual channels at various wavelengths and for simultaneously demultiplexing said plurality into bands by utilizing first bandpasses, each of said bands having a plurality of said individual channels that are separated by at least one other of said channels; and a plurality of second stage WDMs for simultaneously demultiplexing said individual channels from each of said bands with second bandpasses that are wider than said first bandpasses.
Claim 2
Dependent Claim
101 words
A comb splitting system for demultiplexing an optical signal into a plurality of individual channels at various wavelengths, comprising: first stage wavelength division multiplexer (WDM) for receiving said optical signal having said plurality of individual channels at various wavelengths and for simultaneously demultiplexing said plurality into bands by utilizing first bandpasses, each of said bands having a plurality of said individual channels that are separated by at least one other of said channels; and a plurality of second stage WDMs for simultaneously demultiplexing said individual channels from each of said bands with second bandpasses that are wider than said first bandpasses.
Claim 3
Dependent Claim
41 words
The system of claim 1, wherein there are NM of said individual channels and M second stage WDMs, each Ith WDM of said M second stage WDMs receiving and demultiplexing a channel I and a channel (M+I) of said NM channels.
Claim 4
Dependent Claim
18 words
The system of claim 1, wherein said first and second stage WDMs reside on a single integrated circuit.
Claim 5
Dependent Claim
30 words
The system of claim 1, wherein said first and second stage WDMs reside within separate discrete electronic components that are connected locally at a node of an optical fiber network.
Claim 6
Dependent Claim
38 words
The system of claim 1, wherein said first and second stage WDMs are separated and reside at different nodes of an optical fiber network and are interconnected via a fiber cable so that a distribution network is formed.
Claim 7
Dependent Claim
22 words
The system of claim 1, wherein at least one of said first and second stage WDMs each further comprise a Dragone router.
Claim 8
Dependent Claim
24 words
The system of claim 1, further comprising optical fibers configured to transfer said bands from said first stage WDM to said second stage WDMs.
Claim 9
Dependent Claim
23 words
The system of claim 1, further comprising waveguides configured to transfer said bands from said first stage WDM to said second stage WDMs.
Claim 10
Dependent Claim
16 words
The system of claim 1, wherein said channels are approximately equally spaced along a frequency spectrum.
Claim 11
Dependent Claim
34 words
The system of claim 1, further comprising a power splitter associated with each said WDM, said power splitters configured to collectively demultiplex a plurality of power channels that are multiplexed on said optical signal.
Claim 12
Dependent Claim
20 words
The system of claim 2, wherein at least one of said first and second stage WDMs comprises a Fourier filter.
Claim 13
Dependent Claim
102 words
A comb splitting system for multiplexing a plurality of individual channels at various wavelengths into an optical signal, comprising: a plurality of first stage wavelength division multiplexers (WDMs) for producing bands by simultaneously multiplexing said individual channels with first bandpasses, each of said bands having a plurality of said individual channels that are separated by at least one other of said channels; and a second stage wavelength division multiplexer (WDM) for providing said optical signal having said plurality of individual channels at various wavelengths by simultaneously multiplexing said bands by utilizing second bandpasses, said second bandpasses being narrower than said first bandpasses.
Claim 14
Dependent Claim
102 words
A comb splitting system for multiplexing a plurality of individual channels at various wavelengths into an optical signal, comprising: a plurality of first stage wavelength division multiplexers (WDMs) for producing bands by simultaneously multiplexing said individual channels with first bandpasses, each of said bands having a plurality of said individual channels that are separated by at least one other of said channels; and a second stage wavelength division multiplexer (WDM) for providing said optical signal having said plurality of individual channels at various wavelengths by simultaneously multiplexing said bands by utilizing second bandpasses, said second bandpasses being narrower than said first bandpasses.
Claim 15
Dependent Claim
39 words
The system of claim 12, wherein there are NM of said individual channels and M second stage WDMs, each Ith WDM of said M second stage WDMs multiplexing a channel I and a channel (M+I) of said NM channels.
Claim 16
Dependent Claim
15 words
The system of claim 12, wherein said first and second stage WDMs are passive elements.
Claim 17
Dependent Claim
22 words
The system of claim 12, wherein at least one of said first and second stage WDMs each further comprise a Dragone router.
Claim 18
Dependent Claim
24 words
The system of claim 12, further comprising optical fibers configured to transfer said bands from said first stage WDM to said second stage WDMs.
Claim 19
Dependent Claim
23 words
The system of claim 12, further comprising waveguides configured to transfer said bands from said second stage WDMs to said first stage WDM.
Claim 20
Dependent Claim
16 words
The system of claim 12, wherein said channels are approximately equally spaced along a frequency spectrum.
Claim 21
Dependent Claim
34 words
The system of claim 12, further comprising a power splitter associated with each said WDM, said power splitters configured to collectively multiplex a plurality of power channels that are multiplexed on said optical signal.
Claim 22
Dependent Claim
20 words
The system of claim 12, wherein at least one of said first and second stage WDMs comprises a Fourier filter.
Claim 23
Dependent Claim
13 words
The system of claim 13, wherein N is 2 and M is 2.
Claim 24
Dependent Claim
13 words
The system of claim 13, wherein N is 4 and M is 8.
Claim 25
Dependent Claim
118 words
A comb splitting system for demultiplexing an optical signal having a plurality of individual channels at respective wavelengths into the individual channels, comprising: (a) a first stage for receiving said optical signal that has NM channels, said first stage having a wavelength division multiplexer (WDM) configured to simultaneously demultiplex said NM channels into M bands; (b) a second stage having M WDMs configured to receive a respective band and to simultaneously demultiplex individual channels from said respective bands, each of said bands having channels I and (M+I) at each Ith WDM; and (c) wherein said M WDMs of said second stage have wider bandpasses for demultiplexing said channels than those bandpasses of said WDM of said first stage.
Claim 26
Dependent Claim
118 words
A comb splitting system for demultiplexing an optical signal having a plurality of individual channels at respective wavelengths into the individual channels, comprising: (a) a first stage for receiving said optical signal that has NM channels, said first stage having a wavelength division multiplexer (WDM) configured to simultaneously demultiplex said NM channels into M bands; (b) a second stage having M WDMs configured to receive a respective band and to simultaneously demultiplex individual channels from said respective bands, each of said bands having channels I and (M+I) at each Ith WDM; and (c) wherein said M WDMs of said second stage have wider bandpasses for demultiplexing said channels than those bandpasses of said WDM of said first stage.
Claim 27
Dependent Claim
14 words
The system of claim 23, wherein said first and second stages are passive networks.
Claim 28
Dependent Claim
19 words
The system of claim 23, wherein said WDMs of said first and second stages each comprise a Dragone router.
Claim 29
Dependent Claim
22 words
The system of claim 23, further comprising optical fibers configured to transfer said bands from said first stage to said second stage.
Claim 30
Dependent Claim
21 words
The system of claim 23, further comprising waveguides configured to transfer said bands from said first stage to said second stage.
Claim 31
Dependent Claim
16 words
The system of claim 23, wherein said channels are approximately equally spaced along a frequency spectrum.
Claim 32
Dependent Claim
21 words
The system of claim 23, wherein said WDMs each comprise a Fourier filter and wherein M and N both equal 2.
Claim 33
Dependent Claim
34 words
The system of claim 23, further comprising a power splitter associated with each said WDM, said power splitters configured to collectively demultiplex a plurality of power channels that are multiplexed on said optical signal.
Claim 34
Dependent Claim
13 words
The system of claim 23, wherein N is 2 and M is 2.
Claim 35
Dependent Claim
13 words
The system of claim 23, wherein N is 4 and M is 8.
Claim 36
Dependent Claim
90 words
A comb splitting method for demultiplexing an optical signal into a plurality of individual channels at respective wavelengths, comprising the steps of: receiving said optical signal having said plurality of individual channels at various wavelengths; simultaneously demultiplexing bands of individual channels from said plurality by utilizing first bandpasses in a first WDM, said channels in each of said bands being separated by at least one other channel; and simultaneously demultiplexing individual channels from each of said bands with second bandpasses in second WDMs that are wider than said first bandpasses.
Claim 37
Dependent Claim
90 words
A comb splitting method for demultiplexing an optical signal into a plurality of individual channels at respective wavelengths, comprising the steps of: receiving said optical signal having said plurality of individual channels at various wavelengths; simultaneously demultiplexing bands of individual channels from said plurality by utilizing first bandpasses in a first WDM, said channels in each of said bands being separated by at least one other channel; and simultaneously demultiplexing individual channels from each of said bands with second bandpasses in second WDMs that are wider than said first bandpasses.
Claim 38
Dependent Claim
88 words
A comb splitting method for multiplexing a plurality of individual channels at respective wavelengths to form an optical signal, comprising the steps of: receiving said plurality of individual channels at various wavelengths; simultaneously multiplexing said individual channels from said plurality into bands by utilizing first bandpasses in a first WDM, said channels in each of said bands being separated by at least one other channel; and producing said optical signal by simultaneously multiplexing said bands with second bandpasses in second WDMs that are narrower than said first bandpasses.
Claim 39
Dependent Claim
88 words
A comb splitting method for multiplexing a plurality of individual channels at respective wavelengths to form an optical signal, comprising the steps of: receiving said plurality of individual channels at various wavelengths; simultaneously multiplexing said individual channels from said plurality into bands by utilizing first bandpasses in a first WDM, said channels in each of said bands being separated by at least one other channel; and producing said optical signal by simultaneously multiplexing said bands with second bandpasses in second WDMs that are narrower than said first bandpasses.
References Cited (Backward Citations)
US5002350A
Cited
US5243672A
Cited
US5339157A
Cited
US5373516A
Cited
US5542010A
Cited
US5341444A
Cited
US5461685A
Cited
US5473719A
Cited
US5493625A
Cited
US5412744A
Cited
US5488680A
Cited
US5488500A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-10-20 | 2001-04-21 | 2001-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-10-20 | 2005-04-21 | 2005-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-10-20 | 2009-04-21 | 2009-10-21 | $7700.00 | Window Closed / Lapsed |