Invalidity dossier
US 11973579
Add/drop multiplexer, network system, transmission method, non-transitory computer readable medium, and management device
Current assignee: Radiant Patents LLC
Added 9/23/2026, 10:51:00 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 11,973,579 B2
Title: Add/drop multiplexer, network system, transmission method, non-transitory computer readable medium, and management device
Patent number: US11973579B2 | Application: US17/871,382 | Filed: 2022-07-22 | Granted/Published: 2024-04-30
Priority date (listed as an assumption): 2015-01-27 | Anticipated expiration (listed): 2036-01-25
Inventor: Yurie Matsuyama | Original assignee: NEC Corp | Current assignee (per listing): Radiant Patents LLC
Classifications: H04J14/02, H04J14/0212 (ROADM/WSS arrangements), H04B10/27, H04B10/572
Purpose (per the excerpt): The invention relates to an add/drop multiplexer for optical communication networks using wavelength division multiplexing/demultiplexing. Its stated object is "to provide an add/drop multiplexer capable of arbitrarily changing a device to be connected to the add/drop multiplexer."
Plain-language scope (per the excerpt's summary and definitions): An add/drop multiplexer includes a communication unit that can selectively transfer a received wavelength-multiplexed optical signal, per wavelength, to at least one client device or at least one network; and a control unit that indicates a transfer destination for an optical signal at a given wavelength based on that signal's attribute. The control unit also indicates an attenuation amount corresponding to the transfer destination, and the communication unit attenuates the signal accordingly before transferring it. Corresponding subject matter is described for a network system (add/drop multiplexer plus control device), a transmission method, a control program (receiving change information on a connected device and changing attenuation amount when the connected device changes), and a management device with an interface and control unit. Embodiments illustrated include a network system (FIG. 1), add/drop multiplexer (FIG. 2), communication unit (FIG. 4), wavelength selective switch configurations (FIGs. 5–8), a wavelength path communication node (FIG. 9), and a management device (FIGs. 10–11). The excerpt notes related ROADM technology in "Patent Literature 1 to 4."
Not established by the excerpt: The actual claims, dependent-claim scope, full description, and drawings are omitted, as are the prior-art references' identities. The excerpt is partial ("[Excerpt only; consult the source for omitted text.]"). Dates are described in the source as assumptions. No litigation, ownership-transfer details, validity, or prior-art analysis is provided here.
Generated 10/1/2026, 9:33:07 PM
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Litigation summary
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Proceedings on file (0)
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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