Abstract:
In a terrestrial DMB, a transmitting apparatus multiplexes a plurality of service streams generated for any service to a plurality of ensembles. In this case, the same sending time data is constructed in a time stamp field of each frame for each of a plurality of ensembles. With this configuration, a plurality of transmitting apparatuses can send a plurality of transmission frames including service streams for the same service at the same point of time, and thus receiving apparatuses can actually receive a plurality of transmission frames at the same point of time.
Abstract:
An apparatus for transmitting digital multimedia broadcasting includes: a base layer processor that outputs a base layer stream; an enhancement layer processor that outputs an enhancement layer stream; and a transmitter that modulates the enhancement layer stream based on one of a first and second hierarchical modulation modes using different modulation schemes and maps a symbol of the modulated enhancement layer stream based on a symbol position of the base layer stream to generate a transmission frame.
Abstract:
A transmission apparatus for a broadcast service according to the present invention comprises: a sync layer (SL) packetizer which receives a basic layer elementary stream and an enhanced layer elementary stream and generates SL packets for each stream; a packetized elementary stream (PES) packetizer which converts each of the SL packets into PES packets; a first TS multiplexer unit which multiplexes the PES packets and outputs a basic layer transport stream; and a second TS multiplexer unit which multiplexes the PES packets, and outputs an enhanced layer transport stream, wherein said second TS multiplexer unit inserts, into the enhanced layer transport stream, a descriptor containing information on whether or not the enhanced layer transport stream is dependent on the basic layer transport stream.
Abstract:
A method and apparatus for processing enhanced media data in a Digital Multimedia Broadcasting (DMB) system is provided. The apparatus for processing enhanced media data includes: a base layer processing unit configured to multiplex an elementary stream of a base layer and perform channel encoding for the multiplexed elementary stream of the base layer; an enhancement layer processing unit configured to synchronize an elementary stream of an enhancement layer with the elementary stream of the base layer and thereby multiplex the elementary stream of the enhancement layer and process the elementary stream of the enhancement layer to be transmittable via at least one of a plurality of transmission channels; and a synchronizer configured to provide the enhancement layer processing unit with synchronization information that is used for synchronizing the elementary stream of the enhancement layer with the elementary stream of the base layer.
Abstract:
In order to achieve synchronization of ensemble transport interface (ETI) signals of a first network and a second network, a synchronization device receives a first ETI signal from the first network and a second ETI signal from the second network, generates delay times between the same frames, compares frames of the first ETI signal and frames of the second ETI signal, and then synchronizes the first ETI signal and the second ETI signal according to the delay time.
Abstract:
The present invention relates to a method and apparatus for transmitting digital broadcasting signals and a method and apparatus for receiving digital broadcasting signals that divide a stream into a plurality of layers according to characteristics of the stream, that independently process the layers, and that dynamically allocate frequencies on the basis of the processed signals. A method of transmitting digital broadcasting signals includes dividing a single stream into a plurality of layers according to characteristics of the stream; performing encoding and mapping on each of the layers; and dynamically allocating a frequency to each of the layers on the basis of the number of symbols for each layer.
Abstract:
A data transmitting apparatus generates a plurality of pilot signals to be used in channel estimation in a data receiving apparatus, performs symbol mapping of a plurality of input data signals and a plurality of pilot signals to generate a plurality of data symbols and a plurality of pilot symbols, converts input symbols of a frequency domain including the plurality of data symbols and the plurality of pilot symbols, into real signals of a time domain and performs angle modulation of the real signals. The data transmitting apparatus controls the sizes of sine signals for the angle-modulated real signals by a variable gain in accordance with a control signal, and transmits the real signals.
Abstract:
Provided is a data transmission system using a vertical layer optimisation technique. A data transmission device predicts the buffer state of a data receiving device by using feedback information of a physical layer, and controls data transmission by referring to the predicted buffer state. The data transmission device can control the transmission of first data and second data such that the buffer state of the receiving device is within a preset range.
Abstract:
Provided is a transmitting/receiving method and device for providing a conditional access broadcasting service. A transmitting method for providing a conditional access broadcasting service includes generating a control word (SI 10) for scrambling by- encoding a conditional access subscriber's, and changing the encoded data into an entitlement control message and an entitlement management message including the data generated by classifying the conditional access subscriber and a non-subscriber by activating the data (S120). Also, the method includes generating a final stream by multiplexing (S130) the entitlement control message, the entitlement management message, and a base stream for a first broadcasting service (SI 40), generating a base layer frame and an enhancement layer frame (SI 50) based on the final stream and an enhancement layer stream for a second broadcasting service, generating a broadcasting signal by hierarchically modulating (SI 60) the base layer frame and the enhancement layer frame, and transmitting the broadcasting signal.
Abstract:
A digital multimedia broadcasting transmitting apparatus includes: a variable spreader (120) that spreads a pilot signal to a frequency domain and outputs a signal having a format where the pilot signal is partially inserted to the entire subcarriers; a modulator (130) that modulates the output of the variable spreader (120); and an antenna (140) that transmits the signal modulated by the modulator (130).