Ciena Corporation

Steve W Chaddick

Stephen B Alexander

Cecil D Smith

Roy C Litz

David R Huber

Michael Y Frankel

Victor Mizrahi

The present disclosure provides high-speed wavelength division multiplexing (WDM) transponders (e.g., 10 Gb/s, 40 Gb/s, 100 Gb/s, and beyond) that receive one or more optical signals and convert and/or remodulate the received optical signals onto a newly generated optical channel along with overhead processing/addition, forward error correction, and the like. In general, the transponders of the present invention include a client-side and a line-side, each with bi-directional optical transmission. The transponders provide an effective mechanism to support WDM networks that are transparent to the client-side.

High-speed optical transponder systems

The present invention provides a remodulating channel selector for a wavelength division multiplexed optical communication system. The remodulating selector receives a WDM input signal, selects a particular optical channel from the WDM signal and places the information from the selected signal onto a newly-generated optical output signal. The wavelength of the output optical signal can be the same as or different from one of the optical channels which comprises the WDM input signal. When used in a WDM optical communication system with remodulators at the transmission input, the remodulating selectors provide complete control over the interfaces with optical transmitters and receivers, permitting use with a broad range of optical equipment.

Remodulating channel selectors for WDM optical communication systems

The present invention provides a wavelength division multiplexed optical communication system which includes an optical monitoring channel which is capable of surviving the failure of an optical amplifier. The optical communication system comprises a plurality of optical transmitters which optically communicate with an optical waveguide which carries the multiplexed optical transmission signal. At least one multiple-stage optical amplifier having at least first and second stages is positioned along said optical waveguide. The optical amplifier includes a first and second stages comprising doped fibers having a first gain wavelength band. An optical connecting element having a plurality of ports is positioned between the first and second stages. At least one of an optical monitoring signal transmitter and an optical monitoring signal receiver optical communicates with at least one port of the optical connecting element such that the optical monitoring signal passes through at least one of the first and second stages of the optical amplifier. The optical monitoring signal wavelength is selected to be greater than the longest wavelength of the first gain wavelength band such that the optical monitoring signal is not substantially attenuated by an unpumped optical amplifier. Therefore, in the event of a pump failure to at least a portion of an optical amplifier, the optical monitoring signal will still be transmitted through the that portion of the amplifier without substantial attenuation. In this manner, a wavelength division multiplexed optical communication system is provided with optical monitoring channels which do not occupy a portion of the amplifier gain spectrum and which can survive the failure of an optical amplifier.

Optical monitoring channel for wavelength division multiplexed optical

The present invention provides a WDM optical communication system with remodulators at the transmission input and remodulating channel selectors adjacent the optical receivers, providing complete control over the interfaces with optical transmission equipment. In an exemplary embodiment, the WDM system includes optical transmitters which input transmitted optical signals into optical remodulators. The optical remodulators place the information from each of the transmitted signals onto separate optical channels in the WDM system channel plan. The optical channels are multiplexed onto an optical waveguide. At the receive end, remodulating channel selectors each receive a portion of the WDM optical signal, select a particular optical channel, and place the information from the selected channel onto a newly-generated optical signal. This newly-generated optical signal is output to a receiver or to a further WDM optical system.

WDM Optical communication systems with remodulators and remodulating

A WDM optical communication system is described which is capable of placing information from incoming information-bearing optical signals onto N optical signal channels for conveyance over an optical waveguide. The optical system includes a first set of one or more optical transmitters, each of which emits an information-bearing optical signal at one or more transmission wavelengths, .lambda..sub.Ti. At least M optical receiving systems are provided, each receiving system configured to receive an information-bearing optical signal at a particular reception wavelength .lambda..sub.j, where M is a whole number greater than or equal to N and j is from 1 to M. Each receiving system includes at least one Bragg grating member for selecting the particular reception wavelength .lambda..sub.j. An optical waveguide optically communicates with each of the M receiving systems for transmitting a plurality of optical signals. A plurality of optical remodulators is further included for communicating with the first set of optical transmitters and the optical waveguide. Each optical remodulator is configured to receive an information-bearing optical signal at a transmission wavelength .lambda..sub.Ti and output an information-bearing optical signal at a reception wavelength .lambda..sub.j. A second set of one or more optical transmitters is also provided, each of which emitting a

WDM optical communication system with remodulators and diverse optical

The present invention provides wavelength division multiplexed optical communication systems configured for expansion with additional optical signal channels. In one embodiment, the WDM system comprises N source lasers for producing N optical signal channels, each channel having a unique wavelength where N is a whole number greater than or equal to 2. An optical multiplexer module having N+x inputs, where x is a whole number greater than or equal to 1, optically communicates with each of the N source lasers. The N+x input ports of the multiplexer are configured such that the N input ports are optically coupled to the N source lasers and the x input ports are supplemental ports not optically coupled to the N source lasers. An optical transmission path optically communicates with the multiplexer for carrying a multiplexed optical signal comprising the N optical signal channels. N optical channel selecting modules are provided, each selecting module including a Bragg grating configured to select a unique optical channel wavelength. An optical splitter module optically communicates with the optical transmission path and the optical channel selecting modules. The optical splitter includes N+y output ports, where y is a whole number greater than or equal to 1. The N+y output ports are configured such that each of the N output ports is optically coupled to one of the N optical channel selecting modules and the y output ports are supplemental ports not optically coupled to the N optical channel selecting modules.

Expandable wavelength division multiplexed optical communications systems

The present invention provides an optical communication system capable of placing incoming information-bearing optical signals onto plural optical signal channels for transmission over an optical waveguide. The optical system includes plural optical transmission elements, each transmission element emitting an information-bearing optical signal at a first transmission wavelength. Plural optical receiving systems are provided, each receiving system configured to receive an information-bearing optical signal at a particular reception wavelength. Each receiving system includes an optical filtering member comprising at least one Bragg grating member for selecting the particular reception wavelength. An optical waveguide optically communicates with each of the receiving systems for transmitting a plurality of optical signals. A plurality of optical amplifiers are positioned along the optical waveguide for amplifying plural optical signals simultaneously. A plurality of optical remodulators optically communicates with the optical transmission elements and the optical waveguide. Each optical remodulator is configured to receive an information-bearing optical signal at a transmission wavelength and output an information-bearing optical signal at a reception wavelength corresponding to a channel wavelength of the optical communication system. Each optical remodulator includes an optoelectronic element for receiving an information-bearing optical signal at a transmission wavelength and outputting a corresponding electrical signal which includes the information from the transmission information-bearing optical signal. The remodulator further includes an optical carrier emitting element comprising a light source for transmitting a non-information-bearing carrier optical signal at a reception wavelength. The remodulator additionally comprises an external modulator for imparting information directly onto the carrier optical signal from the electrical Signal. In this manner, incoming transmission signals are placed on the particular optical signal channels employed in the WDM system.

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Annapolis, MD, United States of America

Steve W Chaddick