Abstract: Provided are a control method and system for a cascade hybrid amplifier, in which respective hybrid amplifiers in the cascade hybrid amplifier simultaneously start to implement a pump-starting process comprising: when the hybrid amplifier receives a request to start pumping, determining whether conditions are satisfied, if yes, determining stability of power of an input light of a Raman, starting pumping of an EDFA so that the EDFA enters into an APC operation mode; starting pumping of the Raman, and calculating a gain deviation according to the calculated input light powers before and after pump-starting of the Raman when no reflection alarm exists; and adjusting gain of the Raman according to the gain deviation, and switching to an AGC (automatic gain control) operation mode after the adjustment; and switching the EDFA to the AGC operation mode.

Abstract: Disclosed is a gravity-adapted optical-fiber-connector comprising a gravity-adapted block and at least one gravity connector each including a fiber-stub; tail handle; rear seat being clamped and fixed by gravity-adapted block; elastic device being sleeved on a portion of excircle surface of tail handle and limited by an end face of rear seat and that of tail handle; outer sleeve and optical cable; gravity of gravity-adapted block is applied to elastic device through the end face of rear seat, after the elastic device is compressed, a spring having identical magnitude and direction with the gravity is generated and acted on the end face of tail handle, such that a physical butt-joint-surface of fiber-stub is always applied a preload about the gravity. The gravity-adapted optical-fiber-connector has stable optical-fiber coupling efficiency and coupling performance.

Abstract: A debugging method and device for an operating point voltage of a parallel MZI electro-optical modulator. The parallel MZI electro-optical modulator comprises a Parent MZI (2) formed by a parallel connection of a Child MZI (3) in an I path and a Child MZI (4) in a Q path.

Abstract: The present disclosure relates to a technical field of optical communication, and more particularly to a device and method for matching optical fiber connections for ROADM service side, wherein the device comprises a reference control optical channel transmitter, a downlink WSS, a plurality of emitting ports, a reference control optical channel receiver, an uplink WSS and a plurality of receiving ports; the reference control optical channel transmitter emitting a reference control optical channel signal, and the downlink WSS emitting the reference control optical channel through the respective emitting ports in a polling manner; the reference control optical channel receiver receiving the reference control optical channel signal, and the uplink WSS selectively receiving the reference control optical channel over the plurality of receiving ports in the polling manner; wherein the reference control optical channel operating within an operating wavelength range of WSSs in the ROADM but outside a wavelength range

Abstract: The present invention relates to the field of optical communication, and particularly to a balanced pumping L-band optical fiber amplifier comprising a first erbium-doped optical fiber, a second erbium-doped optical fiber, an absorbing erbium-doped optical fiber and at least two pumping lasers, the first erbium-doped optical fiber, the second erbium-doped optical fiber and the absorbing erbium-doped optical fiber being sequentially arranged in this order, and the at least two pumping lasers providing pumping light; wherein the first erbium-doped optical fiber and the second erbium-doped optical fiber both are injected with forward pumping light and backward pumping light, and the absorbing erbium-doped fiber is arranged downstream of the second erbium-doped optical fiber to absorb amplified spontaneous emission (ASE) generated in the amplifier.

Abstract: The present disclosure relates to a technical field of optical communication, and more particularly to a device and method for matching optical fiber connections for ROADM service side, wherein the device comprises a reference control optical channel transmitter, a downlink WSS, a plurality of emitting ports, a reference control optical channel receiver, an uplink WSS and a plurality of receiving ports; the reference control optical channel transmitter emitting a reference control optical channel signal, and the downlink WSS emitting the reference control optical channel through the respective emitting ports in a polling manner; the reference control optical channel receiver receiving the reference control optical channel signal, and the uplink WSS selectively receiving the reference control optical channel over the plurality of receiving ports in the polling manner; wherein the reference control optical channel operating within an operating wavelength range of WSSs in the ROADM but outside a wavelength range

Abstract: The present invention relates to a technical field of optical communications. It relates to a dual-rate DML device and module, and a calibration method, and in particular, to a dual-rate DML device and module having a built-in signal calibration circuit, and a calibration method. According to the present invention, the signal calibration circuit is added into the device; a PD is prepositioned by means of a novel light splitting structure; a control structure for a sequence-divided multi-channel serial signal is utilized to feed back a monitoring signal to an electric driver to adjust drive current; crosstalk between backlight monitoring is reduced; and high-quality signal output under dual modulation frequencies of 25 Gbps and 28 Gbps is realized.

Abstract: The present disclosure relates to a technical field of optical communication, and provides a method and an apparatus for determining maximum gain of Raman fiber amplifier. Wherein the method includes obtaining transmission performance parameters of a current optical fiber transmission line; respectively obtaining impact factors A1, A2, A4 according to a distance between a joint and a pump source, a fiber loss coefficient, and a fiber length included in the transmission performance parameters; calculating a joint loss value AttAeff according to a distance between a joint and a pump source, a fiber loss coefficient, and looking up impact factor A3 according to AttAeff; determining an actual maximum gain which may actually be achieved by the Raman fiber amplifier according to A1, A2, A3, A4.

Abstract: An optical power and gain detection apparatus including multiple optical power detection circuits, an FPGA device, and a temperature detection circuit. Various optical power detection circuits include a respective independent photoelectric converter, a trans-impedance amplifier, an analog signal conditioning circuit, a filter and an analog-digital conversion chip. By improving an analog circuit, digital detection and control in an optical amplifier, the property of the FPGA device may be used to realize the detection of optical signal and gain in a burst mode, avoid increasing complicated analogue circuits, and avoid the influence caused by element inconsistency in an analogue control solution. Whether the optical signal is in a stable mode or in a burst mode, the algorithm can detect the optical power accurately and stably, with a wide application range. By strictly controlling the synchronism of ADC sampling and the delay of calculation, the amplifier gain may be calculated more accurately.

Abstract: Disclosed is a gravity-adapted optical-fiber-connector comprising a gravity-adapted block and at least one gravity connector each including a fiber-stub; tail handle; rear seat being clamped and fixed by gravity-adapted block; elastic device being sleeved on a portion of excircle surface of tail handle and limited by an end face of rear seat and that of tail handle; outer sleeve and optical cable; gravity of gravity-adapted block is applied to elastic device through the end face of rear seat, after the elastic device is compressed, a spring having identical magnitude and direction with the gravity is generated and acted on the end face of tail handle, such that a physical butt-joint-surface of fiber-stub is always applied a preload about the gravity. The gravity-adapted optical-fiber-connector has stable optical-fiber coupling efficiency and coupling performance.

Abstract: A method and device for controlling a wavelength of a light emitting assembly. The device comprises a microcontroller, a light emitting assembly temperature control unit, an analog-to-digital converter, a digital-to-analog converter, a storage unit, a thermistor of a negative temperature coefficient in a TOSA component, and a TEC assembly. The microcontroller comprises an ADC input interface, a DAC output interface, a GPIO output interface, an external communication interface, and a memory interface. The light emitting assembly temperature control unit comprises a turn-off enable control circuit, a temperature detecting circuit, an error amplification-comparison-compensation unit, a TEC voltage/current limitation circuit, a TEC voltage/current detecting circuit, and a TEC differential voltage driver. The method and device are simple and flexible, implements a precise control of the wavelength, and also considers an adjustment function of the wavelength.

Abstract: A narrow linewidth external cavity semiconductor laser comprises semiconductor optical amplifier chip, comb-shaped optical filter, bandpass optical filter, partial reflection sheet, and collimated light beam coupling output assembly Collimated light beam coupling output assembly is composed of isolator, coupling lens, and output optical fiber. Laser resonant cavity is formed by partial reflection sheet and rear end face of semiconductor optical amplifier chip. Comb-shaped optical filter and bandpass optical filter form single-channel narrowband optical filtering assembly. Bandwidth enables laser to perform single-mode lasing and effectively restrain any other mode lasing. Longitudinal mode's relative position over whole filtering band may be controlled by adjusting laser temperature. Output wavelength and laser power are controlled and in best working state. Etalon is used as comb-shaped optical filter to easily realize narrow linewidth output.

Abstract: A cascade control system of an optical fiber amplifier includes a target setting parameter module, a primary controller, at least one controlled module and a secondary controller corresponding to the controlled module. The control system adopts two or more cascade control loops so that disturbance entering into the secondary loop can be overcome quickly, thereby the dynamic characteristics of the system may be improved. The primary controller aims to coarse adjustment and overall target control, and the secondary controller aims to fine adjustment and quick convergence of a short-term target, so that the control quality of the cascade control system may be further improved. The cascade control system may define the overall control target directly in the primary loop and avoid impact of aging characteristics of some special parameters on the application.

Abstract: An arrayed waveguide grating based hybrid integrated laser has an adjustable external cavity. The waveguide includes a semiconductor gain die and an optical waveguide chip. The optical waveguide chip includes an arrayed waveguide grating and an arrayed waveguide reflection-controllable component. A resonant cavity is formed by the output end reflection-controllable arrayed waveguide grating chip and the semiconductor gain die. An output wavelength of the laser can be adjusted by changing a driving condition of the reflection-controllable component. The output wavelength is determined by a center wavelength of each channel of the arrayed waveguide grating.

Abstract: A debugging method and device for an operating point voltage of a parallel MZI electro-optical modulator. The parallel MZI electro-optical modulator comprises a Parent MZI (2) formed by a parallel connection of a Child MZI (3) in an I path and a Child MZI (4) in a Q path.

Abstract: A wavelength selective switch includes an attenuation liquid crystal cell array and a switching liquid crystal cell array, the attenuation liquid crystal cell array is configured to select a region where a light is incident on the switching liquid crystal cell array; the switching liquid crystal cell array includes a first ECB liquid crystal cell array, which is divided into a plurality of pixel units, a phase of each pixel unit is adjusted by setting different voltages so that a phase pattern formed by the pixel units exhibits a lens property, and the light passing through the switching liquid crystal cell array is deflected by changing a center of the lens formed by the phase pattern, so as to select an outgoing port.

Abstract: Disclosed are an optical multiplexing and demultiplexing module having an automatic discovery function, comprising a signal transmission portion and a signal reception portion. The signal transmission portion transmits information about the optical multiplexing and demultiplexing module by modulating transmission power of a laser. The signal reception portion samples and decodes the received optical power signal to acquire information about the other optical multiplexing and demultiplexing modules borne thereon. In configuring a wavelength division multiplexing transmission system, the device of the present disclosure may simplify the complexity of manual configuration, improve the accuracy of configuration, reduce the cost and failure rate in a solution in which an individual transceiver is used as an automatic discovery function, and adapt to different connection modes.

Abstract: The technology relates to a converged passive optical local access network. The converged passive optical local access network may include a network switch, one or more passive optical splitters, one or more optical network terminals, one or more user devices, and a converged optical line terminal. The converged optical line terminal is integrated into a server and comprised of one or more fiber-optic network interface cards. The converged optical line terminal is configured to manage the transmission of data between the converged passive optical local access network and an external network.

Abstract: A system and method for automatic discovery of an optical cable route. The method comprises: a light source power meter automatically monitoring an attenuation value of an optical cable fiber core, the optical cable fiber core being configured in an optical cable route; when the power meter generates an alarm, determining a level of the optical power alarm and reporting the alarm condition of the optical cable route in real time; and a drive automatically searching for available optical cable routes to provide options of available optical cable routes for real-time allocation of services.

Abstract: A method for realizing precise gain control for a hybrid fibre amplifier, and a hybrid fibre amplifier, in which by an erbium-doped fibre amplifier firstly outputting a constant power, a comparable source signal optical power is provided for a raman fibre amplifier of a next stage. A feedback for the gain control may be formed by comparing a source signal optical power calculated after starting pumping of the Raman fibre amplifier and a source signal optical power detected after pumping stops, thereby greatly improving gain control precision of the Raman fibre amplifier. Moreover, the erbium-doped fibre amplifier parts of all the hybrid fibre amplifiers may simultaneously output a constant optical power, and the Raman amplifier parts of all the hybrid fibre amplifiers may simultaneously start calibration, so that the time for starting operation of the entire system may be improved greatly.