摘要:
An asynchronous transport stream receiver of a digital broadcasting receiving system connected to MPEG-2 (Moving Picture Experts Group-2) equipment, such as a VOD (Video On Demand) server is disclosed. The inventive receiver includes an FIFO section for storing MPEG-2 data generated from DVB-ASI (Digital Video Broadcasting Asynchronous Serial Interface) signals, an oscillator for generating clock signals for producing the MPEG-2 data from the DVB-ASI signals, and a read controller for reading and outputting the MPEG-2 data stored at the FIFO section in synchronization with clock signals of the oscillator. Accordingly, the MPEG-2 data can be processed and outputted regardless of the SD or HD leveled compression condition (bit rate) of the MPEG-2 data transmitted according to the DVB-ASI standard.
摘要:
A system for performing transmission and reception operations based on broadcast/communication convergence. A transmitter adapted for the broadcast/communication convergence converts input broadcast data into a parallel format, inserts port identification (Port ID) information into each of the broadcast data converted into the parallel format and input communication data, multiplexes the broadcast data and the communication data, and transmits a broadcast/communication convergence signal based on a result of the multiplexing through a single transmission channel. A receiver adapted for the broadcast/communication convergence demultiplexes the broadcast/communication convergence signal using the Port ID information to be separated into the broadcast data and the communication data when the broadcast/communication convergence signal is received, and outputs data to a corresponding destination.
摘要:
An optical transmission network is disclosed that classifies digital broadcast channel data according to virtual channel connection (VCC) before transmission. In the optical transmission network, an optical signal receiver converts an optical signal from an optical line terminal (OLT) into an ATM cell that is classified according to the VCC. A VCC-based ATM cell classifier detects header information and a payload part from the classified ATM cell of each VCC. PID analyzers receive a payload part of an ATM cell corresponding to one VCC from the VCC-based ATM cell classifier, extract PID of each broadcast channel from digital broadcast channel data included in the payload part, and output specific broadcast channel data in the broadcast channel data included in the payload part. A switch receives broadcast channel data output from the PID analyzers and switches the received broadcast channel data to a broadcast channel desired by each subscriber. The controller updates broadcast channel information by receiving header information of the classified ATM cell of each VCC from the VCC-based ATM cell classifier, receives the broadcast channel desired by the subscriber, and controls the PID analyzers to output the desired broadcast channel according to VCC information with the desired broadcast channel included therein so that the output broadcast channel is matched to the subscriber.
摘要:
The provided forward error correction (FEC) apparatus for a transmission system includes a low pass filter (LPF) passing only a low frequency component of an input signal having a predetermined transmission rate; an AC power meter converting an energy value of an signal output from the LPF into a DC voltage value; a logarithm amplifier converting the exponentially varying DC voltage value from the AC power meter into a linear logarithmically varying DC voltage value; a digital signal processor (DSP) determining the transmission rate of the input signal according to a magnitude of the linear DC voltage value and outputting a control signal according to the transmission rate; a clock generator receiving the control signal and generating a clock signal according to the control signal; and a FEC module receiving the clock signal and performing FEC operation on the received signal. A method for FEC is also provided.
摘要:
Disclosed is a device for filtering out a null packet in a data stream for example an MPEG-2 TS (Transport Stream) to avoid bandwidth waste when it is transmitted to a backbone network. The device includes a plurality of receiving interfaces, a filter unit, and a controller. The receiving interfaces receive parallel data, such as DVB-ASI (Digital Video Broadcasting-Asynchronous Serial Interface) inputs as channel-by-channel MPEG-2 data. The filter unit counts the respective numbers of data packets and non-data packets of the data input from the receiving interfaces and filters a null packet in the data. A network transmission unit transmits the filtered data to a backbone network. The controller calculates a bit rate based on both of the count numbers received from the filter unit.
摘要:
Disclosed is a device for filtering out a null packet in a data stream for example an MPEG-2 TS (Transport Stream) to avoid bandwidth waste when it is transmitted to a backbone network. The device includes a plurality of receiving interfaces, a filter unit, and a controller. The receiving interfaces receive parallel data, such as DVB-ASI (Digital Video Broadcasting-Asynchronous Serial Interface) inputs as channel-by-channel MPEG-2 data. The filter unit counts the respective numbers of data packets and non-data packets of the data input from the receiving interfaces and filters a null packet in the data. A network transmission unit transmits the filtered data to a backbone network. The controller calculates a bit rate based on both of the count numbers received from the filter unit.
摘要:
An MPTS-SPTS (Multiple Program Transport Stream-Single Program Transport Stream) separation device in a digital broadcasting system includes a receiving interface, an MPTS-SPTS separator, and a transmitting interface. The separator detects a PAT (Program Association Table) packet from among MPEG-2 MPTS packets from a digital broadcast program provider, analyzes PIDs (Program IDs) that correspond respectively to a plurality of programs in an MPEG-2 MPTS packet, receives information of a single program selected by a user, removes packets associated with programs other than the selected program, deletes from the PAT PIDs associated with the other programs, and inserts the changed PAT into a stream corresponding to the selected program.
摘要:
A packet type retransmission system for DMB services includes a DMB device for receiving multimedia data from a content provider, for converting the multimedia data to DMB data for DMB transmission, and for transmitting the DMB data. A broadcasting transfer medium transfers the DMB data transmitted through the DMB device. A DMB-IP converter receives the DMB data transferred through the broadcasting transfer media and converts the DMB data to packet based data. An IP based multimedia transmitting device outputs the packet based multimedia data converted through the DMB-IP converter to user devices.
摘要:
A field programmable gate array (FPGA) for multiplexing data and enable signals input from a plurality of input ports and outputting the multiplexed signal to one output port is disclosed. The FPGA includes a plurality of memories, which are connected to the input ports, for storing the input data and enable signals, respectively, and outputting one-shot signals at trailing edges of the enable signals; and a finite state machine (FSM) for sequentially reading the data signals stored in the memories in an order of the one-shot signals input from the memories.
摘要:
Disclosed is a method of performing a periodical synchronization at a predetermined transmission link for ensuring a start of a super frame in a residential Ethernet system. The method includes the steps of ensuring a start of a first predetermined super frame at the predetermined transmission link, transmitting Sync frames and Async frames through a predetermined number (N-1) of super frames, in which N is a total number of the super frames, and controlling an Async frame to be transmitted at an end point of the (N-1) super frames in such a manner that a start of a next super frame (Nth super frame) is strictly ensured, thereby maintaining a synchronization for the start of the super frame.