Abstract: Provided are a clock synchronization method performed between communication nodes included in a communication network, the clock synchronization method comprises receiving a synchronization source signal through any one of remaining communication nodes except for an uppermost communication node included in the communication network, generating a reference clock for clock synchronization from the received synchronization source signal and transmitting the generated reference clock through a first path including at least a portion reverse to a second path through which a downlink signal is transmitted in the communication network.

Abstract: Provided are an interference cancellation repeater capable of selecting one of a plurality of adaptive filters based on a synchronization signal and canceling interference included in a received signal using the selected adaptive filter and a method of operation thereof.

Abstract: According to one aspect of the disclosure, there is provided a mount bracket for installation of communication device in a structure, the mount bracket including: a bracket body coupled to the structure; a bracket base, to which the communication device is fixed, coupled to the bracket body and rotates to cover the bracket body; and a connection member provided at one end of the bracket body to rotatably connect the bracket base to the bracket body, wherein the bracket base includes an anti-detachment structure for preventing separation from the bracket body during rotation.

Abstract: A communication node included in a multi-antenna multi-carrier system, when precoding matrices corresponding to some subcarriers from among subcarriers allocated to another communication node connected to the communication node are input, obtains precoding matrices for at least some subcarriers from among the allocated subcarriers by performing spherical interpolation on the input precoding matrices, maps the obtained precoding matrices for the at least some subcarriers to the subcarriers allocated to the other communication node, and performs precoding on the plurality of vector signals using the mapped precoding matrices.

Abstract: Provided are a communication node which comprises a signal monitoring device configured to receive a plurality of communication signals transmitted from two or more base stations, and to monitor a bandwidth of each of the received communication signals, a frame setter configured to reset a frame structure by merging at least some of blocks in a preset frame structure according to a result of the monitoring, and a framer configured to frame the plurality of communication signals into one frame by including the plurality of communication signals in a block corresponding to a bandwidth of each of the plurality of communication signals according to the reset frame structure.

Abstract: A communication signal processing method comprises obtaining transmission delay value difference data relating to a difference in transmission delay values in a communication network that varies depending on whether or not a redundant path is used, obtaining redundancy status data relating to whether the redundant path is used, and controlling a parameter of a communication signal transmitted by the communication network based on the transmission delay value difference data when the redundant path is used as a result of determination according to the redundancy status data.

Abstract: A fronthaul multiplexer according to one aspect of the present invention combines uplink packets in a compressed state that is received from two or more radio units so that the uplink packets are accumulated and combined immediately when received or the uplink packets are recompressed using a compressing method with high compression efficiency when stored in a memory in order to reduce a use amount of memory.

Abstract: Provided are a laser diode driver for a multilevel optical signal and a multilevel optical signal transmission device including the same, wherein the laser diode driver includes: a clock generator configured to generate and output a clock signal; a first latch configured to delay output of data corresponding to a first timing of the clock signal from among data sequentially input at each data input period; a second latch configured to delay output of data corresponding to a second timing of the clock signal from among data sequentially input at each data input period; a first synchronization processor configured to output a signal corresponding to the data input by the first latch according to the clock signal; and a second synchronization processor configured to output a signal corresponding to the data input by the second latch according to the clock signal.

Abstract: The present disclosure relates to a method of reducing a Peak to Average Power Ratio (PAPR) in a communication device, and more particularly, to a method of Crest Factor Reduction (CFR) processing of a signal in order to reduce a PAPR in a communication device such as a repeater. The communication device includes: a first CFR module configured generate a first processed signal by CFR processing an original signal; and a second CFR module configured generate a second processed signal by CFR processing the first processed signal, wherein the first processed signal is generated using a first sampling rate, and the second processed signal is generated using a second sampling rate. According to the disclosure, even a communication device with a low sampling rate may effectively remove a peak component of an input signal.

Abstract: Provided is a method of operating a repeater operating in a time division duplex (TDD) mode which comprises detecting a synchronization signal from a received signal, determining a type of a communication period based on the detected synchronization signal and controlling an operation of a signal linearizer based on the determined type of the communication period.

Abstract: Provided are a method of operating a communication system, the method comprises mapping some antennas selected from among a plurality of antennas of each of a plurality of first communication nodes and reception ports of a second communication node, combining uplink signals mapped to an identical reception port of the second communication node from among uplink signals received through the plurality of antennas, and transmitting the combined signals to the mapped reception ports of the second communication node, respectively.

Abstract: There is provided a method of processing uplink Ethernet packets of an aggregation node included in a distributed antenna system, the method includes: receiving a plurality of uplink Ethernet packets; summing the plurality of received uplink Ethernet packets; and transmitting the summed uplink Ethernet packets in an uplink direction.

Abstract: Provided is an optical transceiver including: a receiver configured to receive an optical transmission signal including wavelength information from another optical transceiver through a multiplexer/demultiplexer connected to the receiver; and a controller configured to identify a reception wavelength for communication with the other optical transceiver and to determine a wavelength corresponding to the reception wavelength as a transmission wavelength for communication with the other optical transceiver, based on the wavelength information included in the optical transmission signal.

Abstract: An optical communication device includes: a first multiplexer including a first transmitting port and a second transmitting port; a downstream wavelength analyzer configured to analyze first transmission light to recognize a first downstream wavelength corresponding to the first transmission light and analyze second transmission light to recognize a second downstream wavelength corresponding to the second transmission light; and a controller configured to generate a first control signal for allowing the first transmitting port to pass light corresponding to the first downstream wavelength and allowing the second transmitting port to pass light corresponding to the second downstream wavelength, and output the first control signal to the first multiplexer, wherein the first multiplexer, according to the first control signal, controls the first transmitting port to correspond to the first downstream wavelength and controls the second transmitting port to correspond to the second downstream wavelength.

Abstract: There is provided a method of processing uplink Ethernet packets of an aggregation node included in a distributed antenna system, the method includes: receiving a plurality of uplink Ethernet packets; summing the plurality of received uplink Ethernet packets; and transmitting the summed uplink Ethernet packets in an uplink direction.

Abstract: A distributed antenna system of the present invention implements duplication by a method of configuring a first headend unit and a second headend unit in an active state or in a standby state and connecting a hub unit or a remote unit to the first headend unit and the second headend unit and by a method of connecting, through a redundancy link, a hub unit or remote units of a branch group branched from and connected to each headend unit, activating the redundancy link according to the control of an active headend unit when an error occurs in a frame transmission path, and changing logical port states of a hub unit or remote units that cannot transmit frames due to the error in order to change the frame transmission path so that frame transmission is possible through the activated redundancy link.

Abstract: The disclosure provides a method of operating a distributed antenna system (DAS) interworking with a spectrum sharing system (SSS) including: transmitting, by a node unit of the DAS, DAS information to a management system entity (MSE); generating, by the MSE, linkage information based on the DAS information and radio service device (RSD) information received from at least one RSD of the SSS; transmitting, by the MSE, the interworking information to a system controller of the SSS; receiving, by the MSE, allocation information including a result of allocating shared radio resources to the DAS and the at least one RSD, respectively, according to the interworking information from the system controller; transmitting, by the MSE, the allocation information to the node unit; and operating, by the node unit, according to the allocation information.

Abstract: The present disclosure provides a method of allocating shared radio resources in a spectrum shared system (SSS), the method including: obtaining, by a system controller of the SSS, identification information from at least one radio service device of the SSS and a node unit of a distributed antenna system (DAS); determining, by the system controller of the SSS, whether the at least one radio service device interoperates with the DAS based on the identification information; and allocating, by the system controller of the SSS, the shared radio resources to the at least one radio service device and the DAS, respectively, based on a result of the determining of interoperating.

Abstract: A synchronization method of a communication network, the synchronization method comprises monitoring a connection state of second communication nodes that are synchronized using a synchronization signal provided through a first communication node to which a synchronization source is connected, determining whether the number of the connected second communication nodes exceeds a reference value according to a result of the monitoring and switching a synchronization mode of at least one second communication node when the number of the second communication nodes exceeds a reference value.

Abstract: A communication system comprises a clock generator configured to generate a plurality of system clock signals used to synchronize components included in each of communication nodes in the communication system based on an external clock signal provided by an external clock source located outside the communication system and a physical layer configured to transmit any one of the generated system clock signals to a small cell communicatively connected to an end communication node of the communication system.