Abstract: An analog distributed antenna system having a set of small cells as a signal source is provided. A proposed cellular communication system includes an upper small cell unit including upper protocol processors configured to process an upper first part of a protocol stack of a small cell, a lower small cell unit including lower protocol processors configured to process a remaining second part of the protocol stack of the small cell, and a first matching switch configured to respectively match the lower protocol processors to a plurality of remote units. According to one aspect, the cellular communication system includes a common controller configured to control activation of the plurality of upper protocol processors of the upper small cell unit and the plurality of lower protocol processors of the lower small cell unit according to a required service capacity and appropriately control an operation of the first matching switch.

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: According to an aspect of the present disclosure, a method of processing a data stream in a node unit included in a distributed antenna system includes: receiving frame layout information; changing a frame layout of a predetermined transmission frame based on the received frame layout information; and framing a plurality of data streams based on the changed frame layout.

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

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: 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: Provided is a node unit which is branch-connected to another communication node via a transport medium, the node unit comprising: a delay measurement unit which transmits a test signal for measuring a delay to an adjacent node unit of the branch-connected upper stage via the transport medium and detects a loopback signal to which the test signal is looped back via the adjacent node unit of the upper stage, thereby measuring an upper stage transmission delay between the adjacent node unit of the upper stage and the node unit; a delay summation unit which, when an adjacent node unit of the branch-connected lower stage exists, receives a lower stage transmission delay transmitted from the adjacent node unit of the lower stage, and calculates a summed transmission delay by summing the upper stage transmission delay and the lower stage transmission delay; and a control unit which transmits the summed transmission delay to the adjacent node unit of the upper stage.

Abstract: A synchronization detection method of a repeater comprises receiving a communication signal comprising a plurality of synchronization signal blocks respectively belonging to different frequency ranges, determining a priority of a frequency range in which the plurality of synchronization signal blocks are to be detected based on signal level for each frequency range and detecting a synchronization signal block included in each frequency range according to the determined priority.

Abstract: There is provided a first unit which constitutes a point-to-multipoint communication system and is connected to communicate with each of a plurality of second units. The first unit includes a control signal extraction unit, a signal switching unit and a controller. The control signal extraction unit extracts first control signals respectively transmitted from the plurality of second units. The signal switching unit includes a switching circuit, and selects any one of the first control signals respectively received through individual signal transmission lines. The controller receives the first control signal selected by the signal switching unit, determines an allocation ID to be allocated to a second unit corresponding to the selected first control signal based on the initial identification information of the selected first control signal, and controls the determined allocation ID to be transmitted to the corresponding second unit.

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.

Abstract: The present invention provides a method of optical transmission delay compensation of a system including a main unit and a remote unit, wherein the main unit and the remote unit are connected to each other through an optical transmission line, including: receiving a reference signal, by the remote unit, generated by the main unit through the optical transmission line; analog converting the reference signal and performing analog processing on the reference signal; converting the analog-processed reference signal into an RF signal and radiating the RF signal; and measuring a delay time until the reference signal is generated and radiated as the RF signal. Accordingly, it is possible to obtain an effect of preventing degradation of service quality due to interference by synchronizing remote units and improving the service quality.

Abstract: The present invention, which relates to a multi-path communication device for sharing a feedback path for digital pre-distortion, includes: a DPD processing unit configured to output a plurality of pre-distorted signals by respectively pre-distorting a plurality of input signals, to output an nth control signal when an nth input signal is input, and to output an nth pre-distorted signal using an nth feedback signal input in response to the nth control signal; a power amplifying unit configured to amplify each of the plurality of pre-distorted signals and output a plurality of amplified signals; a signal combining unit configured to combine some of each of the plurality of amplified signals and output combined feedback signal; and a signal selection unit configured to select and output only the nth feedback signal from the combined feedback signal according to the input nth control signal, thereby preventing an increase in the size of a device and manufacturing cost thereof caused by a plurality of DPD feedbac

Abstract: A TSN-based distributed antenna system including a headend unit, one or more TSN switches, and one or more remote units and a fronthaul transport network constituted by the headend unit, the TSN switch, and the remote unit is provided. The packet-based fronthaul network constituted by the headend unit, the TSN switch, and the remote unit transmits traffic in a time-deterministic manner while minimizing packet loss through Ethernet to which TSN standards are applied.

Abstract: The present invention provides a method of optical transmission delay compensation of a system including a main unit and a remote unit, wherein the main unit and the remote unit are connected to each other through an optical transmission line, including: receiving a reference signal, by the remote unit, generated by the main unit through the optical transmission line; analog converting the reference signal and performing analog processing on the reference signal; converting the analog-processed reference signal into an RF signal and radiating the RF signal; and measuring a delay time until the reference signal is generated and radiated as the RF signal. Accordingly, it is possible to obtain an effect of preventing degradation of service quality due to interference by synchronizing remote units and improving the service quality.

Abstract: A head-end device according to an embodiment includes: a plurality of base station interfacing units configured to interface each of transmission/reception signals that are exchanged between the head-end device and a plurality of base stations; and a head-end control unit configured to receive an upper interfacing unit signal transmitted from an upper base station interfacing unit from among the plurality of base station interfacing units, and sequentially transmit the received upper interfacing unit signal to a lower base station interfacing unit.

Abstract: A base station interface device including an interface board, which is located in a housing and determines an upper portion of a first surface as a first mounting location and an upper portion of a second surface opposite to the first surface as a second mounting location, including a relay connector wherein one end is exposed to the upper portion of the first surface and the other end is exposed to the upper portion of the second surface; a base station signal matching unit mounted on the first mounting location and including a first connector coupled to the one end of the relay connector; and a base station signal processing unit mounted on the second mounting location and including a second connector coupled to the other end of the relay connector.

Abstract: Disclosed is an optical network system including a upper network equipment, a lower network equipment, and a plurality of transfer network equipments connecting the upper network equipment and the lower network equipment through independent optical links, wherein the lower network equipment performs switching such that transmission and reception of an optical signal are performed through an optical link of a standby line when a failure occurs in at least one of an optical link used as a working line, an optical interface device associated with the working line in the upper network equipment, and a transfer network equipment associated with the working line.

Abstract: According to an aspect of the inventive concept, there is provided a headend apparatus, including: a spectrum analysis unit analyzing frequency spectrums of a plurality of base station signals to detect characteristic information of the plurality of base station signals; a control unit transmitting the characteristic information to a network management server connected to the headend apparatus and outputting power control information, generated based on the characteristic information, received from the network management server; and a plurality of RF units receiving at least one of the plurality of base station signals and controlling power of the plurality of base station signals based on the power control information and outputting the plurality of base station signals.