Abstract: Disclosed herein is a synchronization method for transmitting a DOCSIS upstream signal, which is performed by an RoIP terminal, the synchronization method including receiving a synchronization (SYNC) message periodically sent by a Cable Modem Termination System (CMTS) and thereby synchronizing a clock and generating a reference time; receiving a ranging request signal from a Cable Modem (CM); including information about a start time of an allocated ranging interval in the ranging request signal, converting the ranging request signal into an IP packet, and transmitting the IP packet to an RoIP headend device over an IP network in order to enable the RoIP headend device to convert the ranging request signal, delivered via the IP network, into an RF signal and transmit the RF signal to the CMTS; and converting a ranging response message delivered from the CMTS into an electric signal and transmitting the electric signal to the CM.

Abstract: Disclosed herein are a method for simultaneously transmitting/receiving upstream and downstream signals using a remote PHY architecture and an apparatus for the same. The method determines whether to divide frequencies depending on whether signal interference occurs among multiple cable modems connected to a cable network, if it is determined to divide the frequencies, categorize the multiple cable modems into multiple groups so that signal interference occurs in each group, but signal interference does not occur between groups, set transmission bands for the multiple groups so that an upstream band and a downstream band of one group alternate with upstream bands and downstream bands of remaining groups by dividing the frequencies in accordance with a number of groups, and cancels, by a remote physical layer (PHY) device located at an optical network terminal of the cable network, self-interference signals for respective groups based on the transmission bands.

Abstract: Disclosed is a method of transmitting broadcasting data and apparatus for the same. According to an embodiment of the present disclosure, the method of transmitting broadcasting data includes: determining at least one IP-based data packet provided in different lengths received from a higher layer; generating a media transport packet having a fixed length by converting the at least one IP-based data packet; and generating broadcasting data by modulating the generated media transport packet on the basis of a broadcasting data modulation scheme and transmitting the broadcasting data.

Abstract: A device for distributing a load and managing power of a virtual server cluster includes a monitoring unit configured to monitor a load distribution condition on server nodes included in a server cluster and a dynamic state of each of the server nodes, a server node information storage unit configured to store static state information of each of the server nodes, a policy determination unit configured to determine a load distribution policy and a power management policy for each of the server nodes using monitoring information and the static state information stored in the server node information storage unit, and a controller configured to control conversion of each of the server nodes into an active state or an inactive state according to the power management policy, and distribution of a load of a service request requested by a service client to activated server nodes according to the load distribution policy.

Abstract: A method of estimating an integer frequency offset and compensating for the integer frequency offset by an estimated error is provided. A frequency offset estimation method may include receiving a reception signal including PLC data and a physical layer link channel (PLC) preamble, detecting first position information on a position of a subcarrier of the PLC preamble in a frequency axis from the reception signal through a cross-correlation between the PLC preamble and the reception signal, detecting second position information on the position of the subcarrier of the PLC preamble defined in a transmission end by restoring the PLC data, and calculating a frequency offset by comparing the first position information with the second position information.

Abstract: Disclosed are a roll-off period detection method, a symbol starting point detection method, a fractional frequency offset estimating method, and an OFDM downstream system using the same. A method of detecting a roll-off period in an OFDM downstream system according to an embodiment of the present disclosure may include: generating a temporary roll-off period by applying a windowing function to a signal having a preset length; and detecting a roll-off period based on any one of a cross correlation and a sum of differences between a detection target signal included in a range of two OFDM symbol signals based on a detection starting point, and the temporary roll-off period.

Abstract: Provided are an apparatus for retransmitting an advanced television systems committee (ATSC) 3.0 digital TV broadcast and methods of the same, the apparatus including a receiver configured to selectively receive at least one of an ATSC 3.0 based digital broadcast signal and an ATSC 3.0 based Internet Protocol (IP) packet input through a first network, a controller configured to generate a moving picture experts group-2 transport stream (MPEG-2 TS) packet by converting audio/video (A/V) packets and signaling information to be received at a second network based on an output signal of the receiver, and extract and provide broadcast program information for a system information (SI) system of a digital broadcast headend to generate an SI table related to a broadcast program converted to MPEG-2 TS, and a transmitter configured to transmit broadcast data to which the MPEG-2 TS packet is converted and the broadcast program information through the second network.

Abstract: Disclosed herein are an apparatus and method for detecting an upstream RF signal based on a preamble. The apparatus for detecting an upstream RF signal based on a preamble includes an analog-to-digital converter unit for receiving an RF analog signal and converting the same into an RF digital signal; a down-converter unit for converting the RF digital signal into a baseband digital signal; a packet detection unit for performing packet detection by performing an operation on the baseband digital signal and preset differential preamble signals; and a timing calculation unit for generating timing information of a terminal device based on the baseband digital signal and time information generated through the packet detection.

Abstract: Disclosed herein are an apparatus and method for converting a broadcast signal. The apparatus for converting a broadcast signal includes a demultiplexer unit for receiving a terrestrial broadcast signal and generating a terrestrial signaling signal, a signaling conversion unit for converting the terrestrial signaling signal into a cable signaling signal by parsing the terrestrial signaling signal, a cable multiplexer unit for generating a cable broadcast signal by multiplexing the cable signaling signal, and a cable modulation unit for modulating the cable broadcast signal and transmitting the cable broadcast signal over a cable network.

Abstract: Disclosed herein is a synchronization method for transmitting a DOCSIS upstream signal, which is performed by an RoIP terminal, the synchronization method including receiving a synchronization (SYNC) message periodically sent by a Cable Modem Termination System (CMTS) and thereby synchronizing a clock and generating a reference time; receiving a ranging request signal from a Cable Modem (CM); including information about a start time of an allocated ranging interval in the ranging request signal, converting the ranging request signal into an IP packet, and transmitting the IP packet to an RoIP headend device over an IP network in order to enable the RoIP headend device to convert the ranging request signal, delivered via the IP network, into an RF signal and transmit the RF signal to the CMTS; and converting a ranging response message delivered from the CMTS into an electric signal and transmitting the electric signal to the CM.

Abstract: Disclosed are a smart learning system using a device social relation and a method thereof. The smart learning system includes a first device that generates a device social relation and shares learning content, and at least one second device that executes an event related to the learning content by acquiring the shared learning content when is included in the device social relation.

Abstract: A method of estimating an integer frequency offset and compensating for the integer frequency offset by an estimated error is provided. A frequency offset estimation method may include receiving a reception signal including PLC data and a physical layer link channel (PLC) preamble, detecting first position information on a position of a subcarrier of the PLC preamble in a frequency axis from the reception signal through a cross-correlation between the PLC preamble and the reception signal, detecting second position information on the position of the subcarrier of the PLC preamble defined in a transmission end by restoring the PLC data, and calculating a frequency offset by comparing the first position information with the second position information.

Abstract: Disclosed herein is technology for controlling transmission of a switched digital video service through which an operator management and control system for efficiently managing and controlling a switched digital video transmission system, which may improve utilization of frequency resources, may be simply constructed and managed. To this end, a method for controlling transmission of a switched digital video service includes configuring a multicast session based on information about a request to transmit a video, which is transmitted from a user end; forming and controlling a service flow to be transmitted through the multicast session; allocating and managing a frequency channel resource through which the service flow is to be transmitted; and sharing information about the frequency channel resource and allocation thereof with a switched digital video control module and managing and controlling the switched digital video control module.

Abstract: The preset invention is directed to a building energy management system and method, more specifically to a building energy management system and method that can quickly detect and control an abnormal situation or an emergency situation that may occur within a building.

Abstract: Disclosed are an apparatus and a method for soft-decision demodulating in non-square quadrature amplitude modulation. The apparatus includes: a signal receiving unit receiving a quadrature amplitude modulation (QAM) modulated signal at an m modulation degree at a transmitting side; a soft-decision bit calculating unit determining a soft-decision bit value by calculating log likelihood ratios (LLRs) for m bits of the received QAM modulated signal; and a signal decoding unit restoring the received QAM modulated signal based on the determined soft-decision bit value, in which the soft-decision bit calculating unit defines a log likelihood ratio calculation equation by approximating soft-decision boundary points of constellation points for m bits of non-square QAM having odd bits, respectively.

Abstract: An apparatus and method for transmitting moving picture experts group (MPEG)-2 transport stream (TS) broadcasting data for a broadcasting service based on a physical layer transmission standard defined in a Data over Cable Service Interface Specification (DOCSIS) 3.1. The apparatus includes a converter configured to receive an input of broadcasting data including a plurality of MPEG-2 TS packets and to convert the broadcasting data to a first file with a forward error correction (FEC) codeword structure, and an encoder configured to encode the first file.

Abstract: Provided are an apparatus and method for broadcasting-communications convergence in a hybrid fiber coax (HFC) network. The apparatus includes an optical connector configured to receive broadcast data and communication data from a cable broadcasting station through an optical cable, a channel switch configured to receive the broadcast data from the optical connector and select a piece of broadcast data to be transmitted to a subscriber from among pieces of the broadcast data, and a convergence processor configured to receive the communication data from the optical io connector, receive the selected piece of broadcast data from the channel switch, generate broadcasting-communications convergence data by multiplexing the received communication data and the selected piece of broadcast data, and transmit the broadcasting-communications convergence data.

Abstract: A device for distributing a load and managing power of a virtual server cluster includes a monitoring unit configured to monitor a load distribution condition on server nodes included in a server cluster and a dynamic state of each of the server nodes, a server node information storage unit configured to store static state information of each of the server nodes, a policy determination unit configured to determine a load distribution policy and a power management policy for each of the server nodes using monitoring information and the static state information stored in the server node information storage unit, and a controller configured to control conversion of each of the server nodes into an active state or an inactive state according to the power management policy, and distribution of a load of a service request requested by a service client to activated server nodes according to the load distribution policy.

Abstract: A smart device includes a storage unit storing identity information of a counterpart device, a sensing unit sensing an approach by the counterpart device, a control unit determining whether the counterpart device sensed by the sensing unit corresponds to the identity information stored in the storage unit, and a combining processing unit combining a resource of the counterpart device if the counterpart device is determined by the control unit to correspond to the identity information.

Abstract: Disclosed are an apparatus and a method for soft-decision demodulating in non-square quadrature amplitude modulation. The apparatus includes: a signal receiving unit receiving a quadrature amplitude modulation (QAM) modulated signal at an m modulation degree at a transmitting side; a soft-decision bit calculating unit determining a soft-decision bit value by calculating log likelihood ratios (LLRs) for m bits of the received QAM modulated signal; and a signal decoding unit restoring the received QAM modulated signal based on the determined soft-decision bit value, in which the soft-decision bit calculating unit defines a log likelihood ratio calculation equation by approximating soft-decision boundary points of constellation points for m bits of non-square QAM having odd bits, respectively.