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:
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:
The inventive concept relates to a communication device comprising a DPD processor configured to output a plurality of pre-distorted signals by pre-distorting each of a plurality of input signals using an extracted feedback signal, a first signal combiner configured to combine a plurality of feedback signals corresponding to the plurality of pre-distorted signals and output a combined feedback signal, an analog-to-digital converter configured to convert the combined feedback signal into a digital signal and output a digital-converted combined feedback signal and a signal extractor configured to extract the digital-converted combined feedback signal and output the extracted feedback signal.
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 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.
Abstract:
According to an aspect of the inventive concept, there is provided an apparatus for processing an output signal of an analog-digital converter, includes: a first frequency conversion unit for converting a frequency of the output signal of the analog-digital converter so that a band where spurious components exist moves to a band where direct current components exist in the output signal of the analog-digital converter; a spurious component blocking unit for eliminating, from an output signal of the first frequency conversion unit, spurious components which have moved to the band where direct current components exist; and a second frequency conversion unit for restoring a frequency of an output signal of the spurious component blocking unit to the original frequency of the output signal of the analog-digital converter.
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:
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:
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 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.