It is desirable to provide a technology capable of improving reliability in light transmission and convenience at the time of connecting a transmission device to a cable with a simple circuit configuration. A transmitting device is provided which includes a connector receptacle unit connected to an optical-electrical composite cable, in which the connector receptacle unit includes a first electrode group, a second electrode group provided at a position rotated from the first electrode group by 180 degrees about a center of a main body of the connector receptacle unit as a reference, a first connection unit group for transmitting optical signals, and a second connection unit group for transmitting optical signals provided at a position rotated from the first connection unit group for transmitting optical signals by 180 degrees about the center of the main body of the connector receptacle unit as a reference.

A network test instrument is operable to generate an interference profile for a bursty channel of a cable television network. Frequency spectrum data of a received signal is cross-correlated with predetermined frequency spectrum data to identify traces representative of noise. The interference profile may be built from the traces.

Circuitry of a fiber node which is configured to couple to an optical link and an electrical link may comprise an electrical-to-optical conversion circuit for transmitting on the optical link. The circuitry may be operable to receive signals via the optical link. The circuitry may select between or among different configurations of the electrical-to-optical conversion circuit based on the signals received via the optical link. The signals received via the optical link may be intended for one or more gateways served by the fiber node or may be dedicated signals intended for configuration of the circuitry. The circuitry may be operable to generate feedback and insert the feedback into a datastream received from one or more gateways via the electrical link prior to transmitting the datastream onto the optical link.

The present invention relates generally to a passive optical network (PON)-based video overlay pluggable type optical network device that is easily connected and detached from an indoor optical network terminal (ONT) at a subscriber side, which transmits and receives an optical signal in which a video RF optical signal and a PON optical signal are overlaid, wherein a PON board for receiving and processing the PON optical signals and a video RF board for receiving and processing the video RF optical signals are easily removed for replacement from a housing including an optical sub-assembly (OSA), which separates the PON optical signal and the video RF optical signal, and the PON board and the video RF board are individually designed and configured in a removable manner so that interference between the signals is minimized and selective combinations and production are possible according to various types of PONs and video services.

Systems and methods for optical modulation index calibration in a CATV network.

A cable distribution system that includes a headend connected to a plurality of customer devices through a transmission network that includes a remote fiber node that converts digital data to analog data suitable for the plurality of customer devices. The remote fiber node receiving a downstream external protocol interface packet that includes a header portion and a data portion in memory. The remote fiber node encoding and transmitting the data portion to at least one of the plurality of customer devices, wherein the data portion is transferred from the memory using direct memory access based upon a buffer descriptor for the encoding.

A host device uses an intermediate frequency determined based on frequencies of a second-order nonlinear intermodulation distortion component and a harmonic component which are generated in an analog optical link connected to the host device, for example, an analog optical link of a distributed antenna system (DAS), and precompensates for the second-order nonlinear intermodulation distortion component and the harmonic component generated in the analog optical link.

Digital information can be carried on the fiber leg of an access network using binary modulation. Binary modulated data received at an O/E node can then be modulated onto an analog waveform using quadrature amplitude modulation or some other technique for modulating an analog waveform and transmitted over, for example, the coaxial leg of the network. The O/E node may also receive an analog signal, over the coaxial leg, modulated to carry upstream data from subscriber devices. The O/E node may demodulate the upstream signal to recover the upstream data and forward that upstream data over the fiber leg using a binary modulated optical signal.

A half duplex amplifier for a cable network.

Conventional HDMI optical cables are structured to be unable to normally transmit connection detection between HDMI transmission device and reception device, and unable to avoid a communication failure. Therefore, a phenomenon in which an image is distorted or does not appear occurs. By using an HDMI optical cable and an

HDMI optical conversion device in which an electronic circuit switch having a device connection detection function, a voltage converter, a detection sensor, and a detection signal transmission-only wire are embedded in a connector and a cable, respectively, it becomes possible to stably perform connection detection and communication between HDMI transmission device and reception device, and show an image.