Abstract: A soft decision detecting device in a multiple-input multiple-output (MIMO) receiving apparatus detects reception symbols from signals received through a plurality of reception antennas, calculates a variance of interference and noise of the detected reception symbols, and soft-decision-demaps the detected reception symbols by using the variance of interference and noise of the detected reception symbols to thus calculate a soft decision value.

Abstract: A digital demodulation system calculates an I channel value and a Q channel value of a received signal. The digital demodulation system then changes detection levels to obtain non-uniform detection levels. The digital demodulation system then demodulates the received signal bit by bit by using the changed detection levels and the I channel value and the Q channel value.

Abstract: Disclosed is a method of transmitting, by a transmission device, broadcast signals in a frequency-shared terrestrial broadcast system. The method includes generating the broadcast signals including pilot signals arranged at a physical layer frame based on a group identification (ID) defined according to a broadcast service, and transmitting the generated broadcast signals to a reception device, wherein the positions of the pilot signals arranged at the physical layer frame are different by group IDs.

Abstract: Provided are an on-channel repeater and an on-channel repeating method.

Abstract: Provided are an apparatus for addition data transmission includes: an IF broadcasting signal generating unit receiving the broadcast data, and FEC and modulation of the received broadcast data to generate a broadcasting signal in an intermediate frequency (IF) band; an IF addition signal generating unit receiving the addition data to generate an addition signal in the IF band by using direct sequence spread spectrum (DSSS); an average power controlling unit controlling average power of the addition signal in the IF band; a signal combining unit combining the broadcasting signal in the IF band and the addition signal in the IF band to generate a combination signal; an RF upward converting unit upwardly converting the combination signal in a signal in a radio frequency (RF) band to a combination signal in the RF band; and a transmitting unit transmitting the combination signal in the RF band.

Abstract: A method and an apparatus for transmitting additional data in a digital terrestrial broadcasting system are provided. The apparatus includes: a main signal generating unit channel-coding main data and converting the main data into a main signal; an additional signal generating unit channel-coding additional data and converting the additional data into an additional signal; a mixed signal generating unit generating a mixed signal by coupling the main signal and the additional signal to each other; and a mixed signal transmitting unit modulating the mixed signal and transmitting the modulated mixed signal to a receiver through a transmission antenna, wherein the additional data is additional data requested by a specific user possessing the receiver and the specific user provides information on an additional data transmitter.

Abstract: Provided is an apparatus and method for analyzing identification (ID) signals by converting radio frequency (RF) signals which are transmitted with an ID signal added thereto by a transmitting part, e.g., a plurality of transmitters or repeaters, into signals of a desired band; creating ID signals that are identical to the ID signals added to the RF signals; calculating correlation values between the converted signals and the created ID signals based on partial correlation; and extracting channel profile of multi-path signals caused by a channel between the transmitting part and the ID signal analyzing apparatus from the correlation value. The technology of the present research is applied to broadcasting and communication.

Abstract: Modulating method and apparatus in a broadcasting and communication system are provided. The modulating apparatus includes: a first quadrature phase shift keying (QPSK) modulating unit QPSK-modulating first data including in-phase (I) data and quadrature (Q) data to generate a first signal; a phase rotating unit rotating a phase of the first signal by ? to generate a phase rotated signal; a second QPSK modulating unit QPSK-modulating second data different from the first data and including I? data and Q? data to generate a second signal; and a layer modulating unit modulating the phase rotated signal and the second signal to output a final signal.

Abstract: An apparatus for transmitting broadcasting content including a control signal in a broadcasting network, the apparatus includes: a modulator configured to modulate broadcasting content by a predetermined modulation method; a control signal generator configured to generate a control signal for remote control of infrastructure; an adder configured to add the control signal to the modulated broadcasting content; and a DTV transmitter configured to convert the added signal to a DTV broadcasting signal and transmit the DTV broadcasting signal.

Abstract: Provided is an identification signal analyzing apparatus and method for compensating power of a channel profile occurring at a conventional identification signal analyzing apparatus by using a power compensation. The identification signal analyzing apparatus includes: an identification signal generator for generating an identification signal identical to a known identification signal inserted by a transmission device; a partial correlator for calculating a correlation value between a received signal including the known identification signal inserted by the transmission device and the identification signal generated by the identification signal generator through a partial correlation; a power compensator for compensating power of the correlation value calculated by the partial correlator; and a channel profile extractor for extracting a channel profile from the correlation value compensated by the power compensator.

Abstract: Provided is a channel equalizing apparatus and method for improving channel equalization performance in an Orthogonal Frequency Division Multiplexing (OFDM) reception system applied to digital broadcasting or a communication system. The apparatus, includes: a channel estimating unit for performing channel estimation by using a pilot signal of a frequency domain; a digital filtering unit for changing a characteristic of a channel in a time domain based on an estimated channel estimation result; and a channel equalizing unit for performing channel equalization of a frequency domain on the signal after changing the channel characteristic.

Abstract: In a digital broadcasting signal transmission system, a transmission frame includes a frame body and a frame header, and the frame body is divided into a plurality of sub-bands in the frequency domain and is divided into a plurality of symbols in the time domain. The frame header is provided in the former part of the transmission frame and is transmitted with a signal in the time domain. The frame body includes a plurality of services, and the services respectively receive at least one sub-band and at least one symbol. The frame header includes information on the plurality of services, and information on the plurality of services includes information on the sub-band and the symbol to which the services are allocated, information on channel encoding levels of the services, and information on digital modulation levels of the services.

Abstract: Disclosed are a method and an apparatus for transmitting and receiving broadcast data in a digital broadcasting system. The method for transmitting and receiving broadcast data in a digital broadcasting system includes receiving the main data encoded with symbols having a plurality of levels; deciding whether levels of main data symbols encoded with symbols having the plurality of levels belong to a first group; and mapping the main data symbols to extended levels by using modulation values of the additional data if it is decided that the levels of the main data symbols belong to the first group.

Abstract: In a digital broadcasting signal transmission system, a transmission frame includes a frame body and a frame header, and the frame body is divided into a plurality of sub-bands in the frequency domain and is divided into a plurality of symbols in the time domain. The frame header is provided in the former part of the transmission frame and is transmitted with a signal in the time domain. The frame body includes a plurality of services, and the services respectively receive at least one sub-band and at least one symbol. The frame header includes information on the plurality of services, and information on the plurality of services includes information on the sub-band and the symbol to which the services are allocated, information on channel encoding levels of the services, and information on digital modulation levels of the services.

Abstract: An apparatus for transmitting data in a communication system includes: a first repeater configured to repeat information bits of data to be transmitted a first repetition number of times; an interleaver configured to interleave the information bits repeated the first repetition number of times; an accumulator configured to accumulate-code the interleaved information bits; a second repeater configured to repeat the accumulate-coded information bits a second repetition number of times; a puncturer configured to puncture the information bits repeated the second repetition number of times; and a P/S converter configured to convert the punctured information bits and the information bits of the data and output RA-coded information bits.

Abstract: Provided are an apparatus and method for compensating a feedback path distortion in a digital broadcasting signal. The apparatus for improving a performance of a pre-equalizer in a transmitter of a digital broadcasting system having a feedback path for adaptively generating a filter coefficient of the pre-equalizer, includes a reference signal generator for generating a reference radio frequency (RF) signal, a feedback path estimator for estimating transmission band characteristic information for the feedback path based on the reference RF signal generated from the reference signal generator, and a feedback path compensator for compensating a demodulated signal transferred through the feedback path based on the estimated transmission band characteristic information from the feedback path estimator and generating a filter coefficient of the pre-equalizer.

Abstract: The present invention relates to a method and apparatus for transceiving a broadcast signal in a digital broadcast system. The method for transmitting a broadcast signal according to one embodiment of the present invention comprises the following steps: generating a main signal using main data; generating an additional signal, the power of which is lower than that of the main signal, using a plurality of additional data; generating an additional signal frame using the additional signal and a frame header; and generating a broadcast signal using the main signal and an additional signal frame. The frame header is used in selectively extracting the plurality of additional data from the additional signal frame. According to the present invention, additional data can be efficiently transmitted while maintaining compatibility with existing digital broadcasting systems.

Abstract: Provided are a distributed repeater for repeating output signals identical to input signals through a channel different from that of main transmitter signals but identical to channels of other distributed repeaters, and a distributed repeating method thereof. The distributed repeater includes: a pre-processing unit configured to receive a radio frequency (RF) signal transmitted from an external device and demodulate the RF signal into a baseband signal; an equalizer configured to equalize the baseband signal to correct a distortion occurring on a transmission channel; an identification signal generation and insertion unit configured to generate an identification signal for identification of the distributed repeater and network conditioning, and insert the identification signal in the equalized baseband signal; and a post-processing unit configured to convert the baseband signal from the identification signal generation and insertion unit into an RF signal, and send the RF signal.

Abstract: An apparatus and method for calculating a correlation value using a first channel impulse response estimated from a received signal, determining a weight value based on the correlation value, applying the weight value to the first channel impulse response, and estimating a second channel impulse response is provided.

Abstract: Provided is a terrestrial digital broadcasting transmitter. The terrestrial digital broadcasting transmitter may include a Reed-Solomon (RS) encoder to RS-encode an inputted broadcast signal, a forward error correction (FEC) encoder to channel-encode an inputted additional signal associated with the broadcast signal, a selector to select the RS-encoded broadcast signal or the channel-encoded additional signal, and a vestigial side band (VSB) transmitting part to transmit, to a receiver via a transmitting antenna, the selected signal, the selected signal being the RS-encoded broadcast signal or the channel-encoded additional signal selected by the selector.