Abstract: An IEEE 1394-based unidirectional ring system for an indoor backbone network is disclosed. In the ring system, an RG is used for connection to an external large-capacity network, and an SG is connected to the RG. The SG functions as a clock master to synchronize whole clock signals in the system, manages traffic in the indoor backbone network, manages buses in the indoor backbone network, and monitors the physical states of transmission lines in indoor backbone network. The SG and the SPs form a unidirectional ring structure. A plurality of SPs is configured to load the user data over the indoor backbone network or extract user-desired data from the indoor backbone network to provide user-desired services to a user.

Abstract: Disclosed is a duobinary optical transmitter, which includes a laser source for outputting light with a predetermined wavelength; a Mach-Zehnder interferometer-type optical intensity modulator for modulating the intensity of the light according to a three-level data signal inputted through a modulation terminal; a low-pass filter for converting an inputted two-level binary data signal into a three-level data signal through an interference among codes; and, a modulator driver/amplifier for amplifying the three-level data signal and then outputting it to the modulation terminal, wherein the overall bandwidth of the low-pass filter, the modulator driver/amplifier, and the optical intensity modulator corresponds to approximately ¼ of the clock frequency of the two-level binary data signal.

Abstract: An assembly for an optical home network includes a socket having input and output optical fibers, for transmitting optical signals, installed at corresponding positions of both sides of a connection hole. The assembly further includes a plug connected to a device and including input and output optical transmission lines respectively connected to the input and output optical fibers when the plug is inserted into the connection hole of the socket so as to be connected to the socket. The optical signals transmitted through the input and output optical fibers pass through the socket when the plug is not connected to the passive socket, and are transmitted to the device through the plug when the plug is connected to the socket.

Abstract: Disclosed is a temperature-compensating device for an APD optical-receiver system using an APD (Avalanche Photo Diode). The device includes a temperature-compensating circuit which employs a digital potentiometer capable of linear compensation through data look-up in compensating the decrease in gain caused by the temperature change of the APD.

Abstract: An assembly for an optical home network includes a socket having input and output optical fibers, for transmitting optical signals, installed at corresponding positions of both sides of a connection hole. The assembly further includes a plug connected to a device and including input and output optical transmission lines respectively connected to the input and output optical fibers when the plug is inserted into the connection hole of the socket so as to be connected to the socket. The optical signals transmitted through the input and output optical fibers pass through the socket when the plug is not connected to the passive socket, and are transmitted to the device through the plug when the plug is connected to the socket.

Abstract: A network service platform apparatus employing an IEEE 1394 protocol is disclosed. The network service platform apparatus includes a first optical transceiver connected to an external service gateway to receive downstream data from the external service gateway and transfer upstream data to the external service gateway, a first IEEE 1394 physical unit connected to the first optical transceiver to perform a physical layer operation of an IEEE 1394 protocol with respect to the downstream data, and to transfer the upstream data to the first optical transceiver, and an IEEE 1394 link unit connected to the first IEEE 1394 physical unit to deliver isochronous data of the downstream data by performing a link layer operation of the IEEE 1394 protocol, and to send asynchronous data to be delivered to the service gate to the first IEEE 1394 physical unit as upstream data by performing the link layer operation of the IEEE 1394 protocol with respect to the asynchronous data.

Abstract: An IEEE 1394-based unidirectional ring system for an indoor backbone network is disclosed. In the ring system, an RG is used for connection to an external large-capacity network, and an SG is connected to the RG. The SG functions as a clock master to synchronize whole clock signals in the system, manages traffic in the indoor backbone network, manages buses in the indoor backbone network, and monitors the physical states of transmission lines in indoor backbone network. The SG and the SPs form a unidirectional ring structure. A plurality of SPs is configured to load the user data over the indoor backbone network or extract user-desired data from the indoor backbone network to provide user-desired services to a user.

Abstract: Disclosed is a temperature-compensating device for an APD optical-receiver system using an APD (Avalanche Photo Diode). The device includes a temperature-compensating circuit which employs a digital potentiometer capable of linear compensation through data look-up in compensating the decrease in gain caused by the temperature change of the APD.

Abstract: Disclosed is a duobinary optical transmitter, which includes a laser source for outputting light with a predetermined wavelength; a Mach-Zehnder interferometer-type optical intensity modulator for modulating the intensity of the light according to a three-level data signal inputted through a modulation terminal; a low-pass filter for converting an inputted two-level binary data signal into a three-level data signal through an interference among codes; and, a modulator driver/amplifier for amplifying the three-level data signal and then outputting it to the modulation terminal, wherein the overall bandwidth of the low-pass filter, the modulator driver/amplifier, and the optical intensity modulator corresponds to approximately ¼ of the clock frequency of the two-level binary data signal.