Abstract:
Disclosed are a method and a device for transmitting and receiving a signal, the method including: identifying a downlink signal-only transmission section in which a first electronic device transmits a downlink signal to a second electronic device, and transmitting the signal in the downlink signal-only transmission section; detecting at least one symbol that has a power value relatively higher than a predetermined threshold value; estimating, on the basis of the detected at least one symbol, an interference channel in which a self-interference signal occurs; detecting the self-interference signal; and identifying an FDX transmission section in which an uplink signal is received from the second electronic device and the downlink signal is transmitted simultaneously, and processing transmission of the downlink signal and reception of the uplink signal in the FDX transmission section, wherein the reception of the uplink signal is processed by removing the self-interference signal occurring in the interference channel.
Abstract:
Disclosed is a an apparatus for reducing a reducing a peak to average power ratio (PAPR) for layer division multiplexing (LDM) in an orthogonal frequency division multiplexing (OFDM) system, the apparatus may include a peak remover configured to detect a peak power value of a subcarrier signal that is input and generate a peak removal signal that decreases the detected peak power value, and a processor configured to perform constellation remapping on a first signal generated by combining the subcarrier signal and the peak removal signal and then generate a second signal into which additional data is inserted.
Abstract:
Disclosed are a roll-off period detection method, a symbol starting point detection method, a fractional frequency offset estimating method, and an OFDM downstream system using the same. A method of detecting a roll-off period in an OFDM downstream system according to an embodiment of the present disclosure may include: generating a temporary roll-off period by applying a windowing function to a signal having a preset length; and detecting a roll-off period based on any one of a cross correlation and a sum of differences between a detection target signal included in a range of two OFDM symbol signals based on a detection starting point, and the temporary roll-off period.
Abstract:
A method of estimating an integer frequency offset and compensating for the integer frequency offset by an estimated error is provided. A frequency offset estimation method may include receiving a reception signal including PLC data and a physical layer link channel (PLC) preamble, detecting first position information on a position of a subcarrier of the PLC preamble in a frequency axis from the reception signal through a cross-correlation between the PLC preamble and the reception signal, detecting second position information on the position of the subcarrier of the PLC preamble defined in a transmission end by restoring the PLC data, and calculating a frequency offset by comparing the first position information with the second position information.
Abstract:
An apparatus and a method for processing an uplink signal of cable broadcasting network including: modulating uplink data to be transmitted to a broadcasting station which is located at an end of the cable broadcasting network into a plurality of symbols; performing a correlation-coding on the plurality of symbols; and outputting an analog radio frequency (RF) signal corresponding to the plurality of correlation-coded symbols are provided.
Abstract:
When a disaster occurs, a disaster information transmitting apparatus generates disaster information, spreads the disaster information with a spreading code, modulates the spread disaster information, and transmits the modulated disaster information using a guard band of a broadcasting frequency band.
Abstract:
In an orthogonal frequency division multiplexing (OFDM) wireless communication system, by modulating a phase of a symbol signal of source data to transmit and by performing constellation mapping of additional data having a coded channel and a signal having a modulated phase, a transmitting signal in which the additional data and the signal having a modulated phase are coupled is generated and transmitted.
Abstract:
Disclosed are a method for acquiring synchronization in a cable network, and a physical (PHY) transmitter and PHY receiver. The method for acquiring synchronization in a cable network according to an embodiment includes receiving, by a PHY receiver, a signal from a PHY transmitter, and acquiring, by the PHY receiver, channel synchronization when a symbol in which a channel preamble exists is detected from the received signal and a position of a frequency in which a channel subcarrier exists is detected from the detected symbol by performing a cross correlation operation on the received signal and the channel preamble.
Abstract:
A method and apparatus for transmitting an OFDM signal including converting a distribution of a signal in which inverse Fourier transform is performed in an OFDM system and a method of receiving an OFDM signal including expanding a received signal are provided, and by changing a magnitude distribution of a signal that is output from an OFDM modulator to a bimodal Gaussian distribution, an influence of noise in a receiving terminal can be reduced, and by limiting a signal that is output from an OFDM modulator to an appropriate magnitude, a phase in the receiving terminal can be prevented being wrongly demodulated.