Abstract: A gas sensing system includes a signal generator including a wavelength tunable laser, the signal generator providing a first periodic signal and a second periodic signal, wherein the first periodic signal comprises a wavelength scanning signal and the second periodic signal comprises a modulation signal; an optical signal absorption path which is wavelength selective, wherein the generated signal covers at least one of the absorbance band; a signal detector that uses lock-in detection to detect a second harmonic of the second periodic signal after absorption, the signal detector further including a local reference generator, a multiplier, and a low pass filter; a local reference includes a first path (ref1) that outputs sinusoidal signal with frequency equals to that of the second signal in signal generator, and a second path (ref2) that outputs sinusoidal signal of two times ref1 frequency; and a local reference generator having a first phase shifter that is configurable from 0 to 2? and a second phase shif

Abstract: The invention uses a PRBS pattern generated by transmitter (serializer) as training. At the receiver side, following receiver outputs, a synchronous capturing module is used to capture multiple lanes simultaneously. The captured data is used to calculate the PRBS distance for different lanes. After the distances are obtained, the one with largest latency is used as a reference, to calculate the relative latency with each other lane. This relative latency is further used to calculate the number of shifts for Barrel Shifter and word shifter.

Abstract: A switching system includes one or more line card for input processing, forwarding, queuing, and scheduling data, the line card having a tunable laser to select a wavelength according to the packets' destination for a given burst of packets, so that the burst is switched to a desired destination and sent all-optically to a connected interface; an all-optical switch fabric coupled to the line card to perform wavelength switching; and a centralized arbitrator that resolves the contention from different input ports.

Abstract: A method is provided for traffic aggregation in a hitless protected packet switched network having source and destination nodes. The method includes enabling a working path and a protecting path between the source and destination nodes. The working path is non-overlapping with respect to the protecting path. The method includes generating, using a processor, internal marker packets at working and protecting input ports of the source nodes. Each market packet represents a respective marker time period. The method includes transmitting the marker packets to working and protecting output ports of the source nodes, by the working and protecting input ports of the source nodes. The method includes selectively aggregating, at each of the working and protecting output ports of the source nodes, hitless traffic sent from different working and protecting inputs ports of the source nodes to provide an aggregated flow there from, responsive to the marker packets.

Abstract: Methods and systems for variable rate control include determining a new communications rate in response to measured data traffic patterns. A receive change message is transmitted to a receiver that triggers the receiver to wait for an end of transmission (EoT) message and to set a new communications rate. A transmit change message is transmitted to a transmitter that triggers the transmitter to send the EoT message to the receiver, to set the new communications rate, and to send a start of transmission (SoT) message to the receiver before resuming data communications.

Abstract: A sensing platform includes a server; one or more remote sensing systems coupled to the central server, including: one or more local sensor(s) for target object monitoring; a wireless module coupled to a network through wireless a link; and a processor to read data from local sensor(s), and communicate information through the network using the wireless module, wherein the sensing system has a low power consumption mode where the processor puts the wireless module and the local sensor(s) in sleep mode or powered off, wherein the processor has a sleep or deep sleep mode, a power-off mode, and a wake up mode, wherein the local sensor(s) are accessed at a frequency 1/T1 and the wireless module is at lower frequency 1/Tw where Tw>T1, wherein the server receives monitored value from remote sensing systems and interacts with the remote sensing system.

Abstract: A gas sensing system includes a signal generator including a wavelength tunable laser, the signal generator providing a first periodic signal and a second periodic signal, wherein the first periodic signal comprises a wavelength scanning signal and the second periodic signal comprises a modulation signal; an optical signal absorption path which is wavelength selective, wherein the generated signal covers at least one of the absorbance band; a signal detector that uses lock-in detection to detect a second harmonic of the second periodic signal after absorption, the signal detector further including a local reference generator, a multiplier, and a low pass filter; a local reference includes a first path (ref1) that outputs sinusoidal signal with frequency equals to that of the second signal in signal generator, and a second path (ref2) that outputs sinusoidal signal of two times ref1 frequency; and a local reference generator having a first phase shifter that is configurable from 0 to 2? and a second phase shif

Abstract: A network switch is disclosed with each port having the function of: electrical processing and optical modulation; electrical processing has the ability to identify packet or frame destination; burst mode transmission and receiving capability; uses its pre-assigned time slot to send to the corresponding destination, or receive from the expected source.

Abstract: A method and system are provided. The method includes applying a quasi-cyclic matrix M to an input vector X? of encoded data to generate a vector Y. The method further includes applying a matrix Q to the vector Y to generate a vector Z. The method also includes recursively generating, using a processor, parity check bits P for the encoded data from the vector Z and an identity matrix variant I*. The encoded data includes quasi-cyclic low-density parity-check code. The identity matrix variant I* is composed of Toeplitz sub-matrices.

Abstract: Methods and systems for flexible-client, flexible-link optical transponders include electrical-to-optical transponders, which accept client data from a flow distributor, and a first multiplexing switch that connects modulated optical carriers from the transponders to line interfaces. The electrical-to-optical transponders each include a flexible optical transport unit (OTU) framer module that compresses multiple optical data units (ODUs) into a single ODU having a higher order than any of the input ODUs to form an optical transport network (OTN) frame. An electrical-to-optical modulator modulates OTN frames onto a carrier. The transponder includes a second multiplexing switch that accepts optical carriers from line interfaces and optical-to-electrical transponders that accept modulated optical carriers from the second multiplexing switch.

Abstract: There are provided an optical transponder having a first end and a second end, as well as an electric switch having the transponder. The transponder includes an optical interface, at the first end, having a variable rate optical transmitter and a variable rate optical receiver to respectively transmit and receive signals using at least one of different bandwidths and different bit rates. The transponder further includes an electrical interface, at the second end, having an electrical interface throughput matching an optical capacity of the optical interface. The transponder also includes a processor for controlling the optical capacity.

Abstract: A method and system are described for providing hitless protection in a packet switched network having source nodes and destination nodes. The method includes enabling a working path and a protecting path between the source and destination nodes. The working path is non-overlapping with respect to the protecting path. The method further includes replicating traffic in a given one of the source nodes to generate replicated traffic. The method also includes forwarding the traffic and the replicated traffic through a working path and a protecting path, respectively, from the given one of the source nodes to a particular one of the destination nodes. The method additionally includes delivering a hitless-protected service in the particular one of the destination nodes by selecting traffic packets received from either the working path or the protecting path.

Abstract: A method for reducing optical components at a receiver which include converting an input signal at a receiver to include an interleaving of alternate signal diversity components, the signal diversity components including phase diversity when the converting includes 0 and 90 degree interleaving and the signal diversity components include polarization diversity interleaving when the converting includes interleaved orthogonal polarizations, and combining the signal diversity components for enabling a single photo detection at the receiver to detect the alternative signal diversity components for subsequent analog-to-digital conversion.

Abstract: An optical amplifier that uses software-defined optical networking (SDON) technology, with a centralized controller and flexible physical hardware (the adaptive amplifier here) to optimize the power distribution among different WDM channels in the amplifier. It considers the detailed information for each channel through the information from centralized controller. It is suitable for both single line rate and mixed line rate system, and is suitable for a wavelength division multiplexing WDM system with the same signal type or different signal types.

Abstract: Methods and systems for flexible-client, flexible-link optical transponders include electrical-to-optical transponders, which accept client data from a flow distributor, and a first multiplexing switch that connects modulated optical carriers from the transponders to line interfaces. The electrical-to-optical transponders each include a flexible optical transport unit (OTU) framer module that compresses multiple optical data units (ODUs) into a single ODU having a higher order than any of the input ODUs to form an optical transport network (OTN) frame. An electrical-to-optical modulator modulates OTN frames onto a carrier. The transponder includes a second multiplexing switch that accepts optical carriers from line interfaces and optical-to-electrical transponders that accept modulated optical carriers from the second multiplexing switch.

Abstract: Systems and methods for packet switching in a network, including two or more hybrid packet/circuit switching network architectures configured to connect two or more core level switches in the network architectures, the network architectures being controlled and managed using a centralized software defined network (SDN) control plane. An optical ring network may be configured to interconnect the two or more hybrid network architectures, and one or more hybrid electrical/optical packet/circuit switches configured to perform switching and traffic aggregation. One or more high-speed optical interfaces and one or more low-speed electrical/optical interfaces may be configured to transmit data.

Abstract: A communication system includes a synchronous interface coupled to a switch fabric; cells for switching; and a 1+1 protection unit with a primary and back-up line cards.

Abstract: A switching system includes one or more line card for input processing, forwarding, queuing, and scheduling data, the line card having a tunable laser to select a wavelength according to the packets' destination for a given burst of packets, so that the burst is switched to a desired destination and sent all-optically to a connected interface; an all-optical switch fabric coupled to the line card to perform wavelength switching; and a centralized arbitrator that resolves the contention from different input ports.

Abstract: In an optical communication system containing a primary line and backup line card, a method includes providing interfaces for the primary and backup line card, each line card including a transmitter and receiver; and selecting output from the transmitter from either the primary or back up line card including selecting the backup line card when the primary line card encounters a failure.

Abstract: A packet switched communication system to support hitless protection includes a packet processor; a traffic manager with a buffer sized to compensate a maximum skew of each hitless path pair of a working path and a protecting path; and a hitless processor positioned between the packet processor and the traffic manager, wherein an interface between hitless processor and traffic manager has flow control to start or stop (XON/XOFF) traffic.