Abstract: An optical receiver is disclosed, including an optoelectronic detector, a transimpedance amplification (TIA) circuit, a single-ended-to-differential converter, an I/O interface, and a controller. The optoelectronic detector, having bandwidth lower than required system transmission bandwidth, converts an optical signal into a current signal. The TIA circuit compensate gain for the received current signal based on a received control signal, to obtain a voltage signal, where a frequency response value of the current signal within first bandwidth is greater than that within the bandwidth of the optoelectronic detector, and any frequency in the first bandwidth is not lower than an upper cut-off frequency of the optoelectronic detector. The single-ended-to-differential converter converts the voltage signal into a differential voltage signal. The I/O interface outputs the differential voltage signal. The controller generates the control signal based on the differential voltage signal.

Abstract: A data transmission method includes receiving, by an optical line terminal (OLT) from an optical network unit (ONU), uplink burst data that includes a synchronization data block and a payload, where the synchronization data block includes first synchronization data, wherein the first synchronization data includes a first preamble and an ONU identifier, and a first bandwidth occupied by the first frequency distribution of the first synchronization data is narrower than a second bandwidth occupied by the second frequency distribution of the payload, and obtaining, by the OLT from the first synchronization data, the ONU identifier.

Abstract: Optical time domain reflectometers and optical subassemblies haying optical tine domain reflectometry functions are provided. In one aspect, an optical time domain reflectometer includes a base and a light splitting film disposed on the base, and the light splitting film includes a first side corresponding to a transmission region and a second, opposite side corresponding to a reflection region. The optical time domain reflectometer further includes a laser and a detector that are respectively located on the transmission region and the reflection region. The light splitting film is configured to: reflect or transmit laser light emitted by the laser out of the base, and reflect or transmit a part of the laser light reflected or scattered by an optical fiber to the detector.

Abstract: An optical receiver is disclosed, including an optoelectronic detector, a transimpedance amplification (TIA) circuit, a single-ended-to-differential converter, an I/O interface, and a controller. The optoelectronic detector, having bandwidth lower than required system transmission bandwidth, converts an optical signal into a current signal. The TIA circuit compensate gain for the received current signal based on a received control signal, to obtain a voltage signal, where a frequency response value of the current signal within first bandwidth is greater than that within the bandwidth of the optoelectronic detector, and any frequency in the first bandwidth is not lower than an upper cut-off frequency of the optoelectronic detector. The single-ended-to-differential converter converts the voltage signal into a differential voltage signal. The I/O interface outputs the differential voltage signal. The controller generates the control signal based on the differential voltage signal.

Abstract: The present disclosure relates to optical receivers. One example optical receiver includes an optoelectronic detector, a transimpedance amplification (TIA) circuit, a single-ended-to-differential converter, an I/O interface, and a controller. The optoelectronic detector, having bandwidth lower than required system transmission bandwidth, converts an optical signal into a current signal. The TIA circuit compensates gain for the received current signal based on a received control signal to obtain a voltage signal, where a frequency response value of the current signal within first bandwidth is greater than that within the bandwidth of the optoelectronic detector, and any frequency in the first bandwidth is not lower than an upper cut-off frequency of the optoelectronic detector. The single-ended-to-differential converter converts the voltage signal into a differential voltage signal. The I/O interface outputs the differential voltage signal.

Abstract: The present disclosure relates to passive optical network (PON) systems, an optical line terminal (OLT), and an optical network unit (ONU). One example PON system includes an OLT and at least two ONUs, and the OLT and the ONUs exchange data on one downstream channel and two upstream channels. The OLT sends downstream data to each ONU on the downstream channel, where the downstream data includes an upstream bandwidth grant which is used to control the ONU to send upstream data. Each ONU receives the downstream data on the downstream channel, and sends the upstream data on a first upstream channel or a second upstream channel based on the upstream bandwidth grant included in the downstream data. The OLT receives, on the first upstream channel and the second upstream channel, the upstream data sent by each ONU.

Abstract: The present disclosure relates to passive optical network (PON) systems, optical line terminals (OTLs), and optical network units (ONUs). One example PON system includes an OLT and at least two ONUs. The OLT and the ONUs exchange data on one downstream channel and two upstream channels. The OLT sends downstream data to each ONU on the downstream channel, where the downstream data includes an upstream bandwidth grant used to control each ONU to send upstream data. Each ONU receives the downstream data on the downstream channel, and sends the upstream data on a first upstream channel or a second upstream channel based on the upstream bandwidth grant included in the downstream data. The OLT receives, on the first upstream channel and the second upstream channel, the upstream data sent by each ONU, where a registration function is disabled on the first upstream channel, and enabled on the second upstream channel.

Abstract: The present disclosure relates to optical receivers. One example optical receiver includes an optoelectronic detector, a transimpedance amplification (TIA) circuit, a single-ended-to-differential converter, an I/O interface, and a controller. The optoelectronic detector, having bandwidth lower than required system transmission bandwidth, converts an optical signal into a current signal. The TIA circuit compensates gain for the received current signal based on a received control signal to obtain a voltage signal, where a frequency response value of the current signal within first bandwidth is greater than that within the bandwidth of the optoelectronic detector, and any frequency in the first bandwidth is not lower than an upper cut-off frequency of the optoelectronic detector. The single-ended-to-differential converter converts the voltage signal into a differential voltage signal. The I/O interface outputs the differential voltage signal.

Abstract: The present disclosure relates to passive optical network (PON) systems, optical line terminals (OTLs), and optical network units (ONUs). One example PON system includes an OLT and at least two ONUs. The OLT and the ONUs exchange data on one downstream channel and two upstream channels. The OLT sends downstream data to each ONU on the downstream channel, where the downstream data includes an upstream bandwidth grant used to control each ONU to send upstream data. Each ONU receives the downstream data on the downstream channel, and sends the upstream data on a first upstream channel or a second upstream channel based on the upstream bandwidth grant included in the downstream data. The OLT receives, on the first upstream channel and the second upstream channel, the upstream data sent by each ONU, where a registration function is disabled on the first upstream channel, and enabled on the second upstream channel.

Abstract: A method for detecting an optical network unit (ONU) in a passive optical network (PON), an ONU, a PON and an optical line terminal (OLT) are disclosed. In an embodiment the method include detecting an ONU identity code in an open uplink empty window or an empty timeslot, wherein the ONU identity code is a specific code stream sequence of the ONU that identifies a single ONU of the plurality of ONUs included in the PON system during the open uplink empty window or the empty timeslot and determining that the single ONU corresponding to the ONU identity code is a rogue ONU according to the ONU identity code.

Abstract: The present invention is related to a method for preparing VIB Group metal oxide particles or dispersions, wherein the VIB Group metal is tungsten or molybdenum. The methods include: 1) providing precursors of VIB Group metal oxide, reductants and supercritical fluids. 2) said VIB Group metal oxide particles, or dispersions are obtained by the reaction between said metal oxide precursors, and reductants are under supercritical state in said supercritical fluids. Especially, said VIB Group metal oxide can be tungsten bronze, molybdenum bronze, or tungsten and molybdenum bronze which can be present by the formula AxByMOz. Wherein, A represents element exists in the form of dopant cation; and B represents element exists in the form of dopant anion; O represents oxygen; 0?x?1, 0?y?1, 0<x+y?1, and 2?z?3.

Abstract: Disclosed is a transparent, flame-retardant thermally-insulating, UV-blocking polymer composite film, comprising sequentially from the top: a flame retardant layer, a base layer, a thermal insulation layer, and a UV-blocking layer, having a total film thickness of 1 ?m to 500 ?m, visible light transmittance greater than 80%, UV light transmittance less than 1%, and near-infrared transmittance less than 10%. Also disclosed is a preparation method for the present transparent, flame retardant thermally-insulating, UV-blocking polymer composite film, the technical processes whereof are simple and easy to execute, involve low production costs, and are suitable for industrial mass production.

Abstract: Embodiments disclose a method and an apparatus for detecting power of an uplink optical signal, an optical line terminal, and an optical network system. The method includes: separately generating a triggering signal that is used for detecting optical power for each uplink optical signal among multiple uplink optical signals to be detected, where the triggering signal of each uplink optical signal has same duration. The method also includes separately detecting power of each uplink optical signal in the duration of the triggering signal of each uplink optical signal.

Abstract: An apparatus and a method for detecting an uplink optical signal. The apparatus includes a memory and a processor, where the processor is configured to determine a remaining bandwidth in a target uplink frame as a test window, where the remaining bandwidth in the target uplink frame indicates an unallocated bandwidth in the target uplink frame, and detect an uplink optical signal in the determined test window. Therefore, a remaining bandwidth obtained after bandwidth allocation in a target uplink frame is used to detect an uplink optical signal, which can effectively use a resource without the need of independently opening a test window and using an extra resource to detect the uplink optical signal, thereby avoiding waste of a resource and improving test efficiency.

Abstract: Embodiments of the present invention disclose a method and an apparatus for detecting an ONU, and a passive optical network system. The method includes detecting an identity code of an ONU in an open uplink empty window or an empty timeslot, and determining that an ONU corresponding to the identity code of the ONU is a rogue ONU according to the identity code of the ONU. A corresponding apparatus and passive optical network system are also provided in the embodiments of the present invention. In the passive optical network system, a rogue ONU is detected and determined quickly and efficiently, and an effect on an uplink service is reduced.

Abstract: A method for detecting an optical network unit (ONU) in a passive optical network (PON), an ONU, a PON and an optical line terminal (OLT) are disclosed. In an embodiment the method include detecting an ONU identity code in an open uplink empty window or an empty timeslot, wherein the ONU identity code is a specific code stream sequence of the ONU that identifies a single ONU of the plurality of ONUs included in the PON system during the open uplink empty window or the empty timeslot and determining that the single ONU corresponding to the ONU identity code is a rogue ONU according to the ONU identity code.

Abstract: Embodiments of the present invention disclose a method and an apparatus for detecting an ONU, and a passive optical network system. The method includes detecting an identity code of an ONU in an open uplink empty window or an empty timeslot, and determining that an ONU corresponding to the identity code of the ONU is a rogue ONU according to the identity code of the ONU. A corresponding apparatus and passive optical network system are also provided in the embodiments of the present invention. In the passive optical network system, a rogue ONU is detected and determined quickly and efficiently, and an effect on an uplink service is reduced.

Abstract: Embodiments disclose a method and an apparatus for detecting power of an uplink optical signal, an optical line terminal, and an optical network system. The method includes: separately generating a triggering signal that is used for detecting optical power for each uplink optical signal among multiple uplink optical signals to be detected, where the triggering signal of each uplink optical signal has same duration. The method also includes separately detecting power of each uplink optical signal in the duration of the triggering signal of each uplink optical signal.

Abstract: An apparatus and a method for detecting an uplink optical signal. The apparatus includes a memory and a processor, where the processor is configured to determine a remaining bandwidth in a target uplink frame as a test window, where the remaining bandwidth in the target uplink frame indicates an unallocated bandwidth in the target uplink frame, and detect an uplink optical signal in the determined test window. Therefore, a remaining bandwidth obtained after bandwidth allocation in a target uplink frame is used to detect an uplink optical signal, which can effectively use a resource without the need of independently opening a test window and using an extra resource to detect the uplink optical signal, thereby avoiding waste of a resource and improving test efficiency.

Abstract: Disclosed is a transparent, flame-retardant thermally-insulating, UV-blocking polymer composite film, comprising sequentially from the top: a flame retardant layer, a base layer, a thermal insulation layer, and a UV-blocking layer, having a total film thickness of 1 ?m to 500 ?m, visible light transmittance greater than 80%, UV light transmittance less than 1%, and near-infrared transmittance less than 10%. Also disclosed is a preparation method for the present transparent, flame retardant thermally-insulating, UV-blocking polymer composite film, the technical processes whereof are simple and easy to execute, involve low production costs, and are suitable for industrial mass production.