Abstract: Proposed is a federated learning system. The federated learning system may comprise: a central server configured to transmit a first parameter of an extractor in a federated learning model including the extractor and a classifier to each of a plurality of client devices, and receive a plurality of first parameters learned from the plurality of client devices to update the federated learning model; and the plurality of client devices configured to train each of the plurality of the first parameters of the federated learning model using a training data set stored in each of the plurality of client devices while maintaining a value of a second parameter value of the classifier in the federated learning model, and to transmit each of the plurality of the trained first parameters to the central server.

Abstract: A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 16200 and a code rate of 2/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for 256-symbol mapping.

Abstract: An apparatus and method for generating a broadcast signal frame for signaling a time interleaving mode are disclosed. An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes a time interleaver configured to generate a time-interleaved signal by performing time interleaving on a BICM output signal; and a frame builder configured to generate a broadcast signal frame including a preamble for signaling a time interleaving mode corresponding to the time interleaver for each of physical layer pipes (PLPs).

Abstract: An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes a combiner configured to generate a multiplexed signal by combining a core layer signal and an enhanced layer signal at different power levels; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time -interleaved signal by performing interleaving that is applied to both the core layer signal and the enhanced layer signal; and a frame builder configured to generate a broadcast signal frame including a preamble for signaling time interleaver information corresponding to the time interleaver, the time interleaver uses one of time interleaver groups, and a boundary between the time interleaver groups is a boundary between Physical Layer Pipes (PLPs) of a core layer corresponding to the core layer signal.

Abstract: A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 64800 and a code rate of 3/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for 256-symbol mapping.

Abstract: An apparatus and method for transmitting broadcast signal to which channel bonding is applied are disclosed. The apparatus according to the present invention includes an input formatting unit configured to generate baseband packets corresponding to a plurality of packet types using data corresponding to a physical layer pipe; a stream partitioner configured to partition the baseband packets into a plurality of partitioned streams corresponding to the plurality of packet types; BICM units configured to perform error correction encoding, interleaving and modulation corresponding to the plurality of partitioned streams, respectively; and waveform generators configured to generate RF transmission signals corresponding to the plurality of partitioned streams, respectively.

Abstract: An apparatus and method for generating a broadcast signal frame corresponding to a time interleaver supporting a plurality of operation modes are disclosed. An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes a combiner configured to generate a multiplexed signal by combining a core layer signal and an enhanced layer signal; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving that is applied to both the core layer signal and the enhanced layer signal; and a frame builder configured to generate a broadcast signal frame including a preamble for signaling time interleaver information corresponding to the time interleaver, the preamble includes a field indicating a start position of a first complete FEC block corresponding to each of physical layer pipes.

Abstract: A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 16200 and a code rate of 4/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for 64-symbol mapping.

Abstract: A parity puncturing apparatus and method for variable length signaling information are disclosed. A parity puncturing apparatus according to an embodiment of the present invention includes memory configured to provide a parity bit string for parity puncturing for the parity bits of an LDPC codeword whose length is 16200 and whose code rate is 3/15, and a processor configured to puncture a number of bits corresponding to a final puncturing size from the rear side of the parity bit string.

Abstract: A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 16200 and a code rate of 3/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for quadrature phase shift keying (QPSK) modulation.

Abstract: The present specification relates to a film for compensating for a viewing angle, which comprises a base substrate; a pattern layer; and an optical layer, and in which the pattern layer has a first surface comprising a flat surface and a second surface facing the first surface, and the second surface comprises a plurality of protrusions comprising a curved surface, thereby improving a contrast ratio and a viewing angle and decreasing a color band phenomenon, and a polarizing plate comprising the same, and a display device comprising the same.

Abstract: An apparatus and method for generating a broadcast signal frame corresponding to a time interleaver supporting a plurality of operation modes are disclosed.

Abstract: Disclosed herein are a gateway-signaling method for frequency/timing offsets and an apparatus for the same. An apparatus for transmitting a broadcast signal according to an embodiment of the present invention includes a frequency/timing decision unit for determining a center frequency to which a frequency offset is applied using a carrier offset, which is identified using a timing and a management packet transmitted through a Studio-to-Transmitter Link (STL); and an RF signal generation unit for generating an RF signal to be transmitted, which corresponds to the center frequency.

Abstract: A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 16200 and a code rate of 10/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for 256-symbol mapping.

Abstract: A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 64800 and a code rate of 4/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for 1024-symbol mapping.

Abstract: A zero padding apparatus and method for fixed length signaling information are disclosed. A zero padding apparatus according to an embodiment of the present invention includes a processor configured to generate a LDPC information bit string by deciding a number of groups whose all bits are to be filled with 0 using a difference between a length of the LDPC information bit string and a length of a BCH-encoded bit string, selecting the groups using a shortening pattern order to fill all the bits of the groups with 0, and filling at least a part of remaining groups, which are not filled with 0, with the BCH-encoded bit string; and memory configured to provide the LDPC information bit string to an LDPC encoder.

Abstract: Disclosed herein are a gateway-signaling method for Multiple-Input Single-Output (MISO) operation and an apparatus for the same. An apparatus for transmitting a broadcast signal according to an embodiment of the present invention includes a predistortion unit for performing predistortion for decorrelating signals corresponding to transmitters using the number of transmitters used for MISO and a transmitter coefficient index that are identified using a timing and management packet transmitted through a Studio-to-Transmitter Link (STL), thereby generating a pre-distorted signal; and an RF signal generation unit for generating an RF transmission signal using the pre-distorted signal corresponding to the transmitter coefficient index.

Abstract: An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes a combiner configured to generate a multiplexed signal by combining a core layer signal and an enhanced layer signal; a power normalizer configured to reduce power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing time-interleaving that is applied to both the core layer signal and the enhanced layer signal; and a frame builder configured to generate a broadcast signal frame including a preamble for signaling start position information and size information for each of Physical Layer Pipes (PLPs). In this case, the Physical Layer Pipes include a core layer physical layer pipe corresponding to the core layer signal and an enhanced layer physical layer pipe corresponding to the enhanced layer signal.

Abstract: An apparatus and method for broadcast signal frame using layered division multiplexing are disclosed. An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes a combiner configured to generate a multiplexed signal by combining a core layer signal and an enhanced layer signal at different power levels; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving that is applied to both the core layer signal and the enhanced layer signal; and a frame builder configured to generate a broadcast signal frame including a preamble for signaling time interleaver information shared by the core layer signal and the enhanced layer signal, using the time-interleaved signal.

Abstract: An optical isolation element comprising, sequentially: a light control film; a first optical path changing element; and a second optical path changing element. The optical isolation element has an excellent optical isolation ratio, and can be manufactured simply and at low cost. Such an optical isolation element can be applied, for example, to the fields of optical communication or laser optics, security and privacy protection, and members for brightness enhancement in displays or military products requiring hiding and covering, and the like.