Described are techniques for determining whether a received audio signal is corrupted or a product of noise, prior to decoding the entire signal. A received audio signal may include both initialization data and encoded payload data. Correspondence between the initialization data and confirmation data may be determined. If the correspondence indicates a match, the audio receiver may continue decoding the audio signal to access the payload data. If the correspondence does not indicate a match, the audio receiver may cease decoding, which may conserve power, computing resources, and time, ensuring that subsequent audio signals are not missed while the audio receiver decodes a false or corrupted signal.

An optical signal transmission method according to an embodiment of the disclosure is an optical signal transmission method in which a processor performs at least part of each operation, and may include an operation of receiving a data stream, an operation of separating at least part of the data stream into three channels, modulating the separated data streams respectively according to M-ary frequency shift keying (M-FSK) scheme so as to produce an FSK modulated signal, an operation of combining a plurality of FSK modulated signals modulated respectively in the three channels, and producing a color modulated signal according to a bit-color mapping table set in advance, and an operation of transmitting the color modulated signal by controlling a light source of the same optical channel based on the color modulated signal.

A receiver for determining sample phase comprises a sync detector to output a sample phase; an interpolator communicatively coupled to the sync detector and to generate a plurality of interpolated phases, wherein each of the interpolated phase and phases within the phase set corresponds to a respective syncword; a calculator communicatively coupled to the interpolator to calculate an error vector magnitude (EVM) of syncword corresponding respectively to each of the interpolated phase and to each of the phase within a phase set, and determine the minimum EVM among EVMs for the syncword corresponding to each of the interpolated phase and the EVM of syncword corresponding to each of the phase within the phase set; and an output unit communicatively coupled to the calculator and configured to sample and output payload signals at the phase corresponding to the minimum EVM.

A method for modulation in a transmitter for transmitting a signal in a wireless communication system according to an embodiment of the present invention comprises: a step for determining a modulation scheme; a step for, if the determined modulation scheme corresponds to a specific modulation scheme, converting encoded information bits to quadrature amplitude modulation (QAM) symbols in accordance with a predetermined QAM modulation order, selecting a sequence corresponding to an element of an integer vector in a predetermined sequence set, repeating the converted QAM symbols for a predetermined sequence length, and outputting signals by multiplying the repeated QAM symbols and the selected sequence; and a step for transmitting the outputted signals to a receiver.

The present disclosure relates to a 5G or pre-5G communication system to be provided for supporting a higher data transfer rate beyond a 4G communication system such as LTE. The present invention relates to a NOMA system based FQAM connection method and an apparatus therefor. The present invention can increase the user transfer rate at a cell boundary. The scheduling method in a wireless communication system, according to an embodiment of the present invention, comprises a step of receiving a signal-to-interference-noise ratio (SINR) value and an alpha value from a terminal; a step of determining, on the basis of the SINR value and the alpha value, a Gaussian SINR value; a step of pairing users on the basis of the Gaussian SINR value; and a step of re-computing MCS on the basis of a re-computed alpha value.

The present invention relates to a transmit diversity method for FQAM and an apparatus therefor. According to the present invention, a transmit diversity method for FQAM and apparatus therefor are provided, the transmit diversity method comprising the steps of: modulating data into at least one FQAM symbol; interleaving a plurality of tones constituting the at least one FQAM symbol such that tones having the same index are located in adjacent resources; and transmitting the at least one interleaved FQAM symbol through at least one transceving unit.

The present disclosure provides a transmission method comprising splitting a block of bits to be transmitted into a number of groups each consisting of k+2q bits, wherein k and q are natural numbers and each of the groups includes a subgroup consisting of k bits and two subgroups each consisting of q bits and performing 2.sup.q-ary QAM modulation on the subgroups of q bits from the groups of k+2q bits to obtain QAM symbols, respectively. The QAM symbols are processed so that two QAM symbols obtained from the two subgroups of q bits in each of the groups of k+2q bits are mapped onto at least two antennas as consecutive processed symbols. Through the use of 2.sup.k-ary FSK modulation, a frequency tone to which the two consecutive processed symbols are allocated is selected according to the subgroup of k bits from each of the groups of k+2q bits before transmission.

The present disclosure relates to methods for communicating data in a wireless communication system, especially a method, performed in a wireless device, for transmitting data from the wireless device to a wireless network node in OFDMA system having multiple resource units. The method comprises obtaining instructions to use at least one of the resource units for data transmission, receiving information regarding a set of allowed combinations of transmission parameters to use when modulating signals, modulating signals from the wireless device based on the combination of the received transmission parameters to create signals having constant amplitude and/or continuous phase in the time domain using a modulation scheme other than Orthogonal Frequency-Division Multiplexing, OFDM, and transmitting the modulated signals in the frequency ranges defined by the used at least one of the resource units.

Disclosed are a method and an apparatus for estimating channel information. A terminal estimates a channel coefficient for each of subcarriers included in each symbol of the received signals, calculates power of the received signal matched to each of the subcarriers, calculates an interference estimation parameter for each of the subcarriers based on the power of the received signal matched to each of the subcarriers and based on power of a channel coefficient for a subcarrier on which the received signal has maximum power among the subcarriers, and calculates a non-Gaussian characteristic parameter of an interference signal related to the received signals based on the interference estimation parameters calculated for the subcarriers of all the symbols of the received signals.

A method and a transmission device of a mobile communication system are disclosed. The method includes determining a modulation method for data transmission, determining the level of a quadrature amplitude modulation (QAM) according to the determined modulation method, determining the amplitude of a carrier wave and the phase of the carrier wave on the basis of the determined QAM level and the data to be transmitted, and, when the determined modulation method is a first modulation method, determining a sequence length, selecting a sequence form among sequences having the determined length according to the data to be transmitted, and generating a symbol modulating the data to be transmitted, on the basis of the selected sequence, the determined amplitude of the carrier wave, and the determined phase of the carrier wave.