摘要:
Provided is an apparatus for transmitting/receiving communication and broadcasting data. The transmitting apparatus includes: a mapper for mapping inputted broadcasting data into a transport stream according to a predetermined standard; a broadcasting buffer for temporarily storing the mapped transport stream for multiplexing; a communication buffer for temporarily storing a communication data stream for multiplexing; a counter for measuring data rate information of a broadcasting stream inputted between two SYNC signals and outputting the measured data rate; an SYNC signal generator for generating an SYNC signal for synchronization between the transmitting apparatus and a receiving part and periodically transmitting the generated SYNC signal; and a multiplexer for multiplexing a communication stream, a broadcasting stream, and an SYNC signal.
摘要:
Provided is an automatic gain control (AGC) apparatus of a cable modem. The apparatus includes: a gain controller for measuring a power level of digital input signals transmitted from outside, accumulating the measured values of the digital input signals for a predetermined period, acquiring an average size of the signals, and calculating an error value between the average signal size and a predetermined signal size; an amplitude control unit for receiving error values adjusted by the gain controller and controlling an amplitude of the signal; a low pass filter for receiving the signal outputted from the amplitude control unit and performing low pass filtering on the signal; and a signal size control unit for receiving the signal obtained from filtering of the low pass filter and controlling the signal size.
摘要:
Provided is a scheduling apparatus and method in a channel bonding transmission system. The apparatus includes: a downstream service identifier storing unit for storing information related to a downstream service identifier (DSID); a packet transmitting unit for transmitting a packet inputted from outside; a packet classifying unit for analyzing the packet and distributing the downstream service identifier; a virtual storing unit for storing the packets by the packet classifying unit; a monitoring unit for checking downstream service identifier information of the packet stored in the virtual storing unit and requesting channel distributing and channel holding; a channel checking unit for checking the status of channels; a scheduling control unit for acquiring channel information from the downstream service identifier storing unit and controlling packet forwarding; a scheduling unit for forwarding the packets; and an output unit for outputting the forwarded packets.
摘要:
Provided is a digital broadcasting conditional access system and method using an Authorization Revocation List (ARL) for preventing an illegal pay broadcasting viewing after a secession time by promptly revoking an entitlement of pay service seceders through a periodical transmission of ARL that is daily or monthly prepared and updated to subscribers. The invention system comprises an ARL providing unit for creating daily and monthly ARLs separately and updating the ARLs based on service secession information of subscribers, a Subscriber Management System (SMS) for receiving service secession requests from subscribers and delivering the requests to the ARL providing unit, a Subscriber Authorization System (SAS) for producing an Entitlement Control Message (ECM) and an Entitlement Management Message (EMM) for subscriber authorization at a receiving end by using the daily and the monthly ARLs managed by the ARL providing unit, and a transmitting unit for periodically transmitting the ECM to subscribers via an in-band channel and the EMM via an out-of-band channel.
摘要:
An apparatus for determining a downstream topology in a hybrid-fiber-coaxial network includes: a signal branching unit for branching a signal received from a cable modem termination system into a plurality of branched signals; a plurality of signal selecting units for selectively receiving a frequency band signal corresponding to a specific downstream channel among the plurality of branched signals; a downstream topology determining unit for analyzing a downstream ambiguity resolution frequency list contained in a channel information message of a downstream primary channel received from the cable modem termination system, collecting in parallel channel information messages with respect to a plurality of downstream channels, and determining a downstream topology at a high speed using the collected channel information messages; and a plurality of packet generating units for setting downstream channel frequency bands of the signal selecting units under control of the downstream topology determining unit, and sending the channel information messages of the collected downstream channels to the downstream topology determining unit.
摘要:
Provided is an automatic gain control (AGC) apparatus of a cable modem. The apparatus includes: a gain controller for measuring a power level of digital input signals transmitted from outside, accumulating the measured values of the digital input signals for a predetermined period, acquiring an average size of the signals, and calculating an error value between the average signal size and a predetermined signal size; an amplitude control unit for receiving error values adjusted by the gain controller and controlling an amplitude of the signal; a low pass filter for receiving the signal outputted from the amplitude control unit and performing low pass filtering on the signal; and a signal size control unit for receiving the signal obtained from filtering of the low pass filter and controlling the signal size.
摘要:
An apparatus for determining a downstream topology in a hybrid-fiber-coaxial network includes: a signal branching unit for branching a signal received from a cable modem termination system into a plurality of branched signals; a plurality of signal selecting units for selectively receiving a frequency band signal corresponding to a specific downstream channel among the plurality of branched signals; a downstream topology determining unit for analyzing a downstream ambiguity resolution frequency list contained in a channel information message of a downstream primary channel received from the cable modem termination system, collecting in parallel channel information messages with respect to a plurality of downstream channels, and determining a downstream topology at a high speed using the collected channel information messages; and a plurality of packet generating units for setting downstream channel frequency bands of the signal selecting units under control of the downstream topology determining unit, and sending the channel information messages of the collected downstream channels to the downstream topology determining unit.
摘要:
A timing lock detection apparatus and method for digital broadcasting receiver are provided. The apparatus includes: a discrete value generator for cyclically selecting a discrete signal value from a continuous timing error signal; a differential calculator for obtaining a difference between the currently selected timing error signal value and a previously selected timing error signal that is a timing jitter signal; a sign variation detector for detecting variation in a sign of the timing jitter signal; a lock control signal generator for discriminating a period based on the detected sign changing time, and controlling a lock step of the loop filter according to a convergence mode of the timing jitter signal at each period; and a lock detection signal generator for generating a lock signal or an unlock signal according to whether the timing jitter signal reaches a steady state and using the current lock step signal.
摘要:
Provided are an apparatus and a method for multimedia data transmission in a cable network using a broadband and physical layer frame structure. The apparatus includes an external network matching module for transmitting data inputted/outputted from/to an external network to a Data Over Cable Service Interface Specification (DOCSIS) Media Access Control (MAC) layer, a DOCSIS MAC processor for transmitting the data from the external network matching module to a corresponding destination, a first downstream physical layer processor for handling an existing standard transmission in the data from the DOCSIS MAC processor, a second downstream physical layer processor for dealing with a new broadband transmission in the data from the DOCSIS MAC processor, and an upstream physical layer processor for providing received data to the DOCSIS MAC processor.
摘要:
A decision feedback equalizing apparatus selectively using a feedback filter and a method thereof are provided. The apparatus includes: an equalizing unit including a feed forward filter (FFF) for correcting a distorted transmission channel by receiving a match-filtered signal and a feedback filter (FBF) for reducing inter symbol interference ISI of the corrected transmission channel for driving only the FFF in a blind mode and driving the FFF and the FBF in a decision directed mode; a diverge/converge determining unit for determining whether the decision feedback equalizing apparatus is diverged or converged using a unit square error obtained through a least unit square algorithm; and a filter controlling unit for controlling the equalizing unit in a blind mode if the decision feedback equalizing apparatus is determined as divergence, and for controlling the equalizing unit in a decision directed mode if the decision feedback equalizing apparatus is determined as convergence.