Abstract: A distributed antenna system includes a headend device for generating a downlink transmission signal by combining a plurality of downlink RF signals in different frequency bands, received from a plurality of base stations, and converting the downlink transmission signal into a downlink optical signal, a main remote device for receiving the downlink optical signal from the headend device, converting the downlink optical signal into the downlink transmission signal, and amplifying the plurality of downlink RF signals included in the downlink transmission signal, and a sub-remote device for receiving the downlink transmission signal distributed from the main remote device, and amplifying the plurality of downlink RF signals included in the received downlink transmission signal.

Abstract: A node unit of distributed antenna system, the node unit comprises a delay measuring part configured to transmit a first test signal for delay measurement to an upper adjacent node unit and detect the first test signal looped back via the upper adjacent node unit and measure a round trip delay between the node unit and the upper adjacent node unit, and a delay providing part disposed on a signal transmission path through which a second test signal for delay measurement, to be transmitted from a lower adjacent node unit, is to be looped back to the lower adjacent node unit, and configured to provide a delay corresponding to the round trip delay.

Abstract: The inventive concept relates to a distributed antenna system (DAS), and more particularly, to an uplink signal transmission operation of each of node units constituting a DAS. A node unit of a DAS includes a signal input/output unit configured to receive m uplink signals from m lower node units and output the m uplink signals, and a multiplexer configured to generate a single uplink signal by selectively outputting any one of the m uplink signals at an interval of a predetermined output time. Accordingly, it is possible to provide a DAS capable of processing and outputting, as one signal, uplink signals received from a plurality of remote units, without any error.

Abstract: A master unit configured to manage a plurality of remote units connected in a ring topology, the master unit comprising: a network management section configured to transmit at least one of a path-state monitoring control signal and a delay measurement control signal to the plurality of remote units in a first direction and a second direction which is a reverse direction of the first direction, and receives an acknowledgement signal in response to the at least one of a path-state monitoring control signal and a delay measurement control signal; and switching control means for transmitting a forward signal received from a base station in the first direction, and transmitting a switching control signal in the second direction when a defect is detected in any remote unit among the plurality of remote units by the network management section.

Abstract: A base station signal matching device is a base station signal matching device mounted in a distributed antenna system for amplifying a received base station signal and transmitting the amplified base station signal to a user terminal. The base station signal matching device includes a first unit for generating first and second branch base station signals by using a power division function based on the base station signal, and transmitting the second branch base station signal to a third unit, and a second unit for matching the first branch base station signal to be suitable for signal processing of the distributed antenna system.

Abstract: The present invention relates to a communication module assembly. The present invention is a communication module assembly which is electrically connected to a communication device and is supplied with power and signal, and can include a connection port unit that is supplied with the power and the signal from the communication device; a cable connection portion which is provided in the connection port unit, and to which cables electrically connected to the communication device is connected; a plurality of communication modules that is stacked on and connected to the connection port unit in a plug-in type; and a guide means for guiding the communication module such that the communication modules are connected to the connection port unit in a central direction.

Abstract: Provided is an interference cancellation relay device. The interference cancellation relay device includes: an interference cancellation unit cancelling an interference signal from an input signal and outputting the input signal from which the interference signal is removed; a gain control unit controlling a gain of an output signal of the interference cancellation unit; and a pre-distortion unit distorting the output signal of the interference cancellation unit, of which the gain is controlled by the gain control unit.

Abstract: The present invention relates to an optical time domain reflectometer using, as a optical source, a polymer wavelength tunable laser which tunes the wavelength of an optical signal by using polymer grating. The optical time domain reflectometer of the present invention tunes the wavelength of a polymer wavelength tunable laser that outputs a constant optical signal and inspects cutting, reflection, and damage of an optical line by separating an optical signal returning from the optical line by an optical filter having a specific central wavelength. Since a optical source having a constant light intensity is used, the present invention has an effect of reducing the nonlinear effect generated in an optical line.

Abstract: Provided are an optical relay system and a method for setting identification information of a remote device in an optical relay system. In particular, provided are an optical relay system and a method for setting identification information of a remote device in an optical relay system in which a donor device generates unique identification information of a remote device based on temporary identification information and characteristic information received from the remote device to automatically set identification information of the remote device, and as a result, the optical relay system can be normally implemented rapidly in initial installation of the optical relay system or a change of an optical relay system environment and convenience of a manager and reliability of a mobile communication service can be improved.

Abstract: There is provided a device for detecting LTE frame synchronization, including: a CP correlator calculating a correlation of a cyclic prefix (CP) included in each orthogonal frequency division multiplexing (OFDM) symbol of an LTE signal processed digital conversion; a frequency offset compensation unit compensating a frequency offset for a synchronization signal in the LTE signal by using a symbol frequency offset calculated based on the CP correlation; a synchronization signal correlation calculation unit performing a correlation calculation in a time domain with respect to the synchronization signal, of which the frequency offset is compensated, by considering a symbol start timing obtained based on the CP correlation; and a frame synchronization detection unit detecting the frame synchronization of the LTE signal based on a result of the correlation calculation for the synchronization signal.

Abstract: A base station signal matching device is a base station signal matching device mounted in a distributed antenna system for amplifying a received base station signal and transmitting the amplified base station signal to a user terminal. The base station signal matching device includes a first unit for generating first and second branch base station signals by using a power division function based on the base station signal, and transmitting the second branch base station signal to a third unit, and a second unit for matching the first branch base station signal to be suitable for signal processing of the distributed antenna system.

Abstract: A distributed antenna system includes a headend device for generating a downlink transmission signal by combining a plurality of downlink RF signals in different frequency bands, received from a plurality of base stations, and converting the downlink transmission signal into a downlink optical signal, a main remote device for receiving the downlink optical signal from the headend device, converting the downlink optical signal into the downlink transmission signal, and amplifying the plurality of downlink RF signals included in the downlink transmission signal, and a sub-remote device for receiving the downlink transmission signal distributed from the main remote device, and amplifying the plurality of downlink RF signals included in the received downlink transmission signal.

Abstract: A communication device for power saving and a method for controlling power thereof are provided. The communication device includes a power amplifying unit and a control unit. The power amplifying unit generates an output signal obtained by amplifying a downlink signal, using a supply voltage, and outputs the output signal. The control unit determines a current state by comparing predetermined downlink reference information with output signal information on the output signal, and, if the current state is an active state as a comparison result, controls the supply voltage to correspond to the output signal information. Accordingly, power for amplifying a signal can be controlled according to communication traffic, thereby preventing consumption of unnecessary power.

Abstract: A remote device of an optical relay system includes first and second remote driving units each extracting transmission signals of different frequency bands from downlink Radio Frequency (RF) signals provided from an optical conversion unit and outputting the transmission signals; and a downlink path control unit receiving the downlink RF signals from the optical conversion unit and transmitting the downlink RF signals to the second remote driving unit through the first remote driving unit, or transmitting the downlink RF signals to the second remote driving unit by bypassing the first remote driving unit.

Abstract: A monitoring device for a distributed antenna system including at least two node units communicatively coupled to each other transmits, to at least one target node unit among the node units, a data dump command for a first target signal passing through a first signal path in the target node unit. The monitoring device receives, from the target node unit, response data corresponding to the data dump command. The monitoring device generates first quality information indicative of the quality of the first target signal by using the response data.

Abstract: A device included in an analog distributed antenna system includes a first analog signal processing unit for receiving an analog communication signal, a first modulation/demodulation unit for converting a digital Ethernet signal received from an Ethernet network into an analog Ethernet signal, a multiplexing unit for multiplexing the analog communication signal signal-processed by the analog signal processing unit and the analog Ethernet signal converted by the modulation/demodulation unit, and a transmission unit for transmitting, to other devices included in the analog distributed antenna system, the analog communication signal and the analog Ethernet signal, which are multiplexed by the multiplexing unit.

Abstract: A distributed antenna system (DAS) according to an aspect of the inventive concept includes a first node unit for receiving first digital data in accordance with a digital interface standard from a base station, converting the first digital data into second digital data in accordance with a DAS frame standard, and a second node unit for receiving the second digital data from the first node unit, and restoring the first digital data based on the second digital data.

Abstract: A distributed antenna system includes a plurality of head-end units for each receiving mobile communication signals from at least one corresponding base station, a hub unit communicatively coupled to the plurality of head-end units, and a plurality of remote units communicatively coupled to the hub unit, wherein the hub unit configured to distribute the mobile communication signals received from each of the plurality of head-end units to the plurality of remote units, wherein each of the plurality of remote units is remotely disposed to transmit the distributed mobile communication signals to a terminal in service coverage, and wherein the hub unit includes a mixing processing stage configured to perform digital mixing processing on the mobile communication signals respectively received from the plurality of head-end units, and a crest factor reduction (CFR) module disposed posterior to the mixing processing stage, with respect to a signal transmission direction.

Abstract: There is provided a distributed antenna system includes a plurality of head-end units configured to receive mobile communication signals from at least one base station, a hub unit connected to each of the plurality of head-end units through a first transport medium, the hub unit distributing the mobile communication signals respectively received from the plurality of head-end units to a plurality of remote units connected thereto through a second transport medium, and the plurality of remote units remotely disposed to transmit the mobile communication signals to a terminal in a service coverage, wherein the hub unit includes a signal summer configured to digitally sum sub-band signals in a same mobile communication service band based on the mobile communication signals.

Abstract: A node unit of a distributed antenna system includes a power supply unit for supplying power for operating the node unit, a digital part operated by the power supplied from the power supply unit, the digital part performing digital processing on input relay signals and outputting the digital-processed relay signals, and a controller for disabling an output of the digital part in response to a first control command for instructing a reset of the power supply unit or a second control command for instructing a reset of the digital part.