Abstract: A method and device for transmitting and receiving a video stream are provided. The transmitting method includes receiving auxiliary information and one or more video streams, and distributing them as one or more pieces of lane data; transmitting the lane data to a receiving device; and receiving a result value that indicates whether a video processing unit for processing one of the one or more video streams works normally. The receiving method includes receiving one or more pieces of lane data that include auxiliary information and one or more video streams; merging the lane data into one or more video streams; selecting a video processing unit based on the auxiliary information, where one or more video processing units process the video streams; generating a result value for the selected video processing unit that indicates whether the video processing unit works normally; and transmitting the result value to a transmitting device.

Abstract: A method and an apparatus for mapping a quadrature amplitude modulation (QAM) symbol. The QAM symbol mapping apparatus includes a frequency checker, which checks frequencies of sub-carriers in an orthogonal frequency division multiplexing (OFDM) symbol; and a data categorizer, which maps data coded for error correction and uncoded data to the sub-carriers based on the checked frequencies, wherein the data categorizer maps a combination of the coded data and the uncoded data with respect to sub-carriers having frequencies lower than a reference frequency.

Abstract: A method and an apparatus for mapping a quadrature amplitude modulation (QAM) symbol. The QAM symbol mapping apparatus includes a frequency checker, which checks frequencies of sub-carriers in an orthogonal frequency division multiplexing (OFDM) symbol; and a data categorizer, which maps data coded for error correction and uncoded data to the sub-carriers based on the checked frequencies, wherein the data categorizer maps a combination of the coded data and the uncoded data with respect to sub-carriers having frequencies lower than a reference frequency.

Abstract: A method and device for transmitting and receiving a video stream are provided. The transmitting method includes receiving auxiliary information and one or more video streams, and distributing them as one or more pieces of lane data; transmitting the lane data to a receiving device; and receiving a result value that indicates whether a video processing unit for processing one of the one or more video streams works normally. The receiving method includes receiving one or more pieces of lane data that include auxiliary information and one or more video streams; merging the lane data into one or more video streams; selecting a video processing unit based on the auxiliary information, where one or more video processing units process the video streams; generating a result value for the selected video processing unit that indicates whether the video processing unit works normally; and transmitting the result value to a transmitting device.

Abstract: Provided are a method and apparatus for generating a preamble of a data packet. The method includes operations of generating a first field, a second field, and a third field; generating a synchronization sequence for synchronization between a data packet transmitter and a data packet receiver, generating a channel estimation sequence (CES) for estimation of a property of a channel in which the data packet is transmitted, and generating an additional sequence indicating an end position of the synchronization sequence in the preamble, and an additional sequence indicating information about a structure of the CES; and respectively recording the synchronization sequence, the additional sequences, and the CES in the first field, the second field, and the third field, thereby generating the preamble.

Abstract: A method of transmitting frequency channel information by a device to which a frequency band is allocated so as to implement frequency sharing without affecting primary services. The method includes: modulating a stream having content into a main signal; generating a channel information signal related to the frequency band allocated to the device; and combining and transmitting the modulated main signal and the channel information signal. Accordingly, frequency sharing can be used for various primary services by enabling a terminal device to obtain information on a used frequency band without increasing the complexity of the terminal device.

Abstract: Provided are a method and apparatus for generating a preamble of a data packet. The method includes operations of generating a first field, a second field, and a third field; generating a synchronization sequence for synchronization between a data packet transmitter and a data packet receiver, generating a channel estimation sequence (CES) for estimation of a property of a channel in which the data packet is transmitted, and generating an additional sequence indicating an end position of the synchronization sequence in the preamble, and an additional sequence indicating information about a structure of the CES; and respectively recording the synchronization sequence, the additional sequences, and the CES in the first field, the second field, and the third field, thereby generating the preamble.