Abstract: An injection locked transmitter for an optical communication network includes a master seed laser source input substantially confined to a single longitudinal mode, an input data stream, and a laser injected modulator including at least one slave laser having a resonator frequency that is injection locked to a frequency of the single longitudinal mode of the master seed laser source. The laser injected modulator is configured to receive the master seed laser source input and the input data stream, and output a laser modulated data stream.

Abstract: A skew compensation system for a coherent optical communication network includes a transmitter modulator having a first driver input for receiving a first signal from a first channel, a second driver input for receiving a second signal from a second channel, a source input for receiving a continuous wave source signal, and a modulation output in communication with an optical transport medium of the network. The system further includes a tunable delay line disposed between the second channel and the second driver input for inserting a pre-determined training sequence onto the second signal prior to the second driver input, and a processor for determining a skew amount between the second signal at the second driver input and the first signal at the first driver input, calculating a pre-compensation value corresponding to the skew amount, and reducing the skew amount at the modulation output according to the pre-compensation value.

Abstract: A full duplex communication network includes an optical transmitter end having a first coherent optics transceiver, an optical receiver end having a second coherent optics transceiver, and an optical transport medium operably coupling the first coherent optics transceiver to the second coherent optics transceiver. The first coherent optics transceiver is configured to simultaneously transmit a downstream optical signal and receive an upstream optical signal. The second coherent optics transceiver is configured to simultaneously receive the downstream optical signal from the first coherent optics transceiver and transmit the upstream optical signal first coherent optics transceiver. At least one of the downstream optical signal and the upstream optical signal includes at least one coherent optical carrier and at least one non-coherent optical carrier.

Abstract: A full duplex communication network includes an optical transmitter end having a first coherent optics transceiver, an optical receiver end having a second coherent optics transceiver, and an optical transport medium operably coupling the first coherent optics transceiver to the second coherent optics transceiver. The first coherent optics transceiver is configured to simultaneously transmit a downstream optical signal and receive an upstream optical signal. The second coherent optics transceiver is configured to simultaneously receive the downstream optical signal from the first coherent optics transceiver and transmit the upstream optical signal first coherent optics transceiver. At least one of the downstream optical signal and the upstream optical signal includes at least one coherent optical carrier and at least one non-coherent optical carrier.

Abstract: An optical line terminal includes an optical comb generator, N downlink channels Dk, and N uplink-photodetectors PDk. The optical comb generator is configured to generate a carrier signal having an optical-frequency-comb spectrum and including N optical tones Tk and N optical tones Rk, k={1, 2, . . . , N}. Each of the N downlink channels Dk is optically coupled to the optical comb generator and is configured to generate a respective downlink signal DSk that includes optical tone Tk modulated by downlink data. Each of the N uplink-photodetectors PDk is configured to receive a respective one of a plurality of modulated uplink signals USk, having optical tone Rk as a carrier signal.

Abstract: An optical communication network includes a downstream optical transceiver. The downstream optical transceiver includes at least one coherent optical transmitter configured to transmit a downstream coherent dual-band optical signal having a left-side band portion, a right-side band portion, and a central optical carrier disposed within a guard band between the left-side band portion and the right-side band portion. The network further includes an optical transport medium configured to carry the downstream coherent dual-band optical signal from the downstream optical transceiver. The network further includes at least one modem device operably coupled to the optical transport medium and configured to receive the downstream coherent dual-band optical signal from the optical transport medium. The at least one modem device includes a downstream coherent optical receiver, and a first slave laser injection locked to a frequency of the central optical carrier.

Abstract: A carrier-phase recovery method includes: (i) applying a first carrier-phase recovery algorithm to complex-valued symbols of a signal received by a product detector, yielding coarse phase-estimates, the signal being modulated per an M-QAM scheme; (ii) modelling the coarse phase-estimates as a weighted sum of M probability-density functions of an M-component mixture model; (iii) optimizing the M probability-density functions with an expectation-maximization algorithm to yield M optimized probability-density functions; (iv) mapping, based on the M optimized probability-density functions, the coarse phase-estimates to one of M symbols corresponding to the QAM scheme, each coarse phase-estimate mapped to a same symbol belonging to a same one of M clusters; (v) applying a second carrier-phase recovery algorithm to each of the M clusters to generate refined phase-estimates each corresponding to a respective coarse phase-estimate; and (vi) mapping, based on the M optimized probability-density functions, each refined

Abstract: Methods, systems, and devices for a decision directed multi-modulus searching algorithm are described. A receiver may receive an optical signal including a set of data symbols. The receiver may iteratively determine a set of centroids for demodulating the set of data symbols (e.g., as part of a training procedure). The centroids may be used to demodulate the set of data symbols according to a modulation constellation associated with the set of data symbols. The training procedure may include, for each data symbol of a subset of data symbols, assigning a centroid of the set of centroids to each data symbol and updating the set of centroids based on assigning the centroid to each data symbol. The receiver may demodulate the set of data symbols based on the updated set of centroids.

Abstract: A method for differentiator-based compression of digital data includes (a) using a subtraction module, subtracting a predicted signal from a sample of an original signal to obtain an error signal, (b) using a quantization module, quantizing the error signal to obtain a quantized error signal, and (c) generating the predicted signal using a least means square (LMS)-based filtering method.

Abstract: A full duplex communication network includes an optical transmitter end having a first coherent optics transceiver, an optical receiver end having a second coherent optics transceiver, and an optical transport medium operably coupling the first coherent optics transceiver to the second coherent optics transceiver. The first coherent optics transceiver is configured to (i) transmit a downstream optical signal at a first wavelength, and (ii) simultaneously receive an upstream optical signal at a second wavelength. The second coherent optics transceiver is configured to (i) receive the downstream optical signal, and (ii) simultaneously transmit the upstream optical signal. The first wavelength has a first center frequency separated from a second center frequency of the second wavelength.

Abstract: An optical network includes a transmitting portion configured to (i) encode an input digitized sequence of data samples into a quantized sequence of data samples having a first number of digits per sample, (ii) map the quantized sequence of data samples into a compressed sequence of data samples having a second number of digits per sample, the second number being lower than the first number, and (iii) modulate the compressed sequence of data samples and transmit the modulated sequence over a digital optical link. The optical network further includes a receiving portion configured to (i) receive and demodulate the modulated sequence from the digital optical link, (ii) map the demodulated sequence from the second number of digits per sample into a decompressed sequence having the first number of digits per sample, and (iii) decode the decompressed sequence.

Abstract: An optical network includes a transmitter portion configured to (i) precode an input digitized stream of symbols into a precoded symbol stream, (ii) pulse shape the precoded symbol stream with an eigenvalue channel matrix, and (iii) transmit the pulse shaped symbol stream over a digital optical link. The optical network further includes a receiver portion configured to (i) recover the pulse shaped symbol stream from the digital optical link, (ii) decompose eigenvalues of the eigenvalue channel matrix from the recovered symbol stream, and (iii) decode the decomposed symbol stream into an output symbol stream.

Abstract: In one aspect, the present disclosure relates to a communications system which, in one embodiment, includes a phase-correlated, orthogonally-polarized, light-stream generator (POLG) for preparing light into phase coherent light streams having defined states of polarization and spectral composition. In one embodiment, the POLG includes a light source configured to emit light having a predetermined wavelength and a polarization apparatus configured to prepare light from the light source into particular states of polarization. The POLG also includes a phase modulator configured to produce light having a plurality of wavelengths and configured to retard the phase of propagation of light with a first state of linear polarization while not retarding the phase of light with a state of linear polarization orthogonal to the first state of linear polarization when an external electric field is applied.

Abstract: In one aspect, the present disclosure relates to a communications system which, in one embodiment, includes a phase-correlated, orthogonally-polarized, light-stream generator (POLG) for preparing light into phase coherent light streams having defined states of polarization and spectral composition. In one embodiment, the POLG includes a light source configured to emit light having a predetermined wavelength and a polarization apparatus configured to prepare light from the light source into particular states of polarization. The POLG also includes a phase modulator configured to produce light having a plurality of wavelengths and configured to retard the phase of propagation of light with a first state of linear polarization while not retarding the phase of light with a state of linear polarization orthogonal to the first state of linear polarization when an external electric field is applied.

Abstract: The telephone plug and jack with transmission various signals, which involves the telephone plug, the telephone jack, and the connecting cable. The telephone jack/(or plug) is installing on the wall of the room or of the office; and the cable, which is connected with jack/(or plug), is connecting with the local telephone networking, this device is using as the client input terminal (access point) of the local telephone networking. It will be input and transmission with various signals at same time, such as audio signal, television signal, video signal, multimedia signal, the various analogue signals and digital signals. This device is a electric product. The telephone plug and jack are made up of plastic, and it's connecting cable is consisted of the twisted-pair cable, the shielded coaxial cable and the fibre-optic cable. Figure is the new improved telephone plug, the telephone jack and the connecting cable.

Abstract: Sometimes there might have mistakes during the surgical operation because of doctor carelessness. According the report of news paper, The accidents of surgical operation hurt patients about 1 million per year only in the U.S. and the number of death patients in surgical operation of doctor mistakes made through carelessness was about hundred thousands per year. The intention of this invention is looking for a way to protect patient from accident injury in surgical operation and to help doctor to avoid the accident happen in the surgical operation prior by observation to surgical operation, and make the appliance which is for specifically designed for use to observable to the process of surgical operation by doctor. This invention is in the field of optical device and electronic image storage device. This invention have observed that the doctor does surgical operate to patient and to record it.