Abstract: Provided is a method of operating a repeater operating in a time division duplex (TDD) mode which comprises detecting a synchronization signal from a received signal, determining a type of a communication period based on the detected synchronization signal and controlling an operation of a signal linearizer based on the determined type of the communication period.

Abstract: A communication node included in a multi-antenna multi-carrier system, when precoding matrices corresponding to some subcarriers from among subcarriers allocated to another communication node connected to the communication node are input, obtains precoding matrices for at least some subcarriers from among the allocated subcarriers by performing spherical interpolation on the input precoding matrices, maps the obtained precoding matrices for the at least some subcarriers to the subcarriers allocated to the other communication node, and performs precoding on the plurality of vector signals using the mapped precoding matrices.

Abstract: Provided are a method of operating a communication system using physical layer division, the method comprises extracting an initial random access signal from an uplink signal, in a first physical layer of a first communication node of the communication system reducing a data amount of the extracted initial random access signal in the first physical layer and calculating a time synchronization error using the initial random access signal with a reduced amount of data, in a second physical layer of a second communication node of the communication system.

Abstract: A method of operating a TDD-based interference cancellation repeater, the method comprises setting a compensation gain of a gain compensator differently in an uplink communication period and a downlink communication period, setting an optimal coefficient of an adaptive filter in the uplink communication period and an optimal coefficient of the adaptive filter in the downlink communication period the same, based on the set compensation gain of the gain compensator and removing an interference signal in the uplink communication period or the downlink communication period according to the set optimal coefficient of the adaptive filter.

Abstract: Provided is a method of operating a repeater operating in a time division duplex (TDD) mode which comprises detecting a synchronization signal from a received signal, determining a type of a communication period based on the detected synchronization signal and controlling an operation of a signal linearizer based on the determined type of the communication period.

Abstract: A method of operating a communication device including a processor and a memory, the method comprises feeding back a downlink communication signal subjected to analog signal processing, generating signal modification information according to a comparison result of the fed-back downlink communication signal and a downlink communication signal before the analog signal processing, generating an interference cancellation signal for canceling interference occurring in an uplink communication signal by the downlink communication signal based on the generated signal modification information and canceling interference occurring in the uplink communication signal by using the generated interference cancellation signal.

Abstract: A method of operating a repeater comprises selecting some of adaptive filter coefficients among a plurality of adaptive filter coefficients of an adaptive filter used for interference cancellation, based on the size of a coefficient, generating a predicted interference signal using the selected adaptive filter coefficients and generating an interference-canceled communication signal from a received signal using the generated predicted interference signal.

Abstract: Provided are an interference cancellation repeater capable of selecting one of a plurality of adaptive filters based on a synchronization signal and canceling interference included in a received signal using the selected adaptive filter and a method of operation thereof.

Abstract: Provided are a synchronization signal detection method performed by a receiver including a processor and a memory, the synchronization signal detection method comprises calculating a PSS correlation value for a primary synchronization signal (PSS) included in a received signal, detecting a frequency offset for the PSS and a timing offset for sampling timing of the received signal and detecting the PSS based on the PSS correlation value, the frequency offset, and the timing offset.

Abstract: A method of operating a repeater comprises selecting some of adaptive filter coefficients among a plurality of adaptive filter coefficients of an adaptive filter used for interference cancellation, based on the size of a coefficient, generating a predicted interference signal using the selected adaptive filter coefficients and generating an interference-canceled communication signal from a received signal using the generated predicted interference signal.

Abstract: A synchronization detection method of a repeater comprises receiving a communication signal comprising a plurality of synchronization signal blocks respectively belonging to different frequency ranges, determining a priority of a frequency range in which the plurality of synchronization signal blocks are to be detected based on signal level for each frequency range and detecting a synchronization signal block included in each frequency range according to the determined priority.

Abstract: A method of operating a communication device including a processor and a memory, the method comprises feeding back a downlink communication signal subjected to analog signal processing, generating signal modification information according to a comparison result of the fed-back downlink communication signal and a downlink communication signal before the analog signal processing, generating an interference cancellation signal for canceling interference occurring in an uplink communication signal by the downlink communication signal based on the generated signal modification information and canceling interference occurring in the uplink communication signal by using the generated interference cancellation signal.

Abstract: Provided are a synchronization signal detection method performed by a receiver including a processor and a memory, the synchronization signal detection method comprises calculating a PSS correlation value for a primary synchronization signal (PSS) included in a received signal, detecting a frequency offset for the PSS and a timing offset for sampling timing of the received signal and detecting the PSS based on the PSS correlation value, the frequency offset, and the timing offset.

Abstract: A method of operating a repeater comprises selecting some of adaptive filter coefficients among a plurality of adaptive filter coefficients of an adaptive filter used for interference cancellation, based on the size of a coefficient, generating a predicted interference signal using the selected adaptive filter coefficients and generating an interference-canceled communication signal from a received signal using the generated predicted interference signal.

Abstract: A method of operating a TDD-based interference cancellation repeater, the method comprises setting a compensation gain of a gain compensator differently in an uplink communication period and a downlink communication period, setting an optimal coefficient of an adaptive filter in the uplink communication period and an optimal coefficient of the adaptive filter in the downlink communication period the same, based on the set compensation gain of the gain compensator and removing an interference signal in the uplink communication period or the downlink communication period according to the set optimal coefficient of the adaptive filter.

Abstract: A synchronization detection method of a repeater comprises receiving a communication signal comprising a plurality of synchronization signal blocks respectively belonging to different frequency ranges, determining a priority of a frequency range in which the plurality of synchronization signal blocks are to be detected based on signal level for each frequency range and detecting a synchronization signal block included in each frequency range according to the determined priority.

Abstract: A repeater including an analog attenuator configured to attenuate an analog signal in response to a first control signal; an analog to digital converter (ADC) configured to convert the attenuated analog signal into a digital signal; a digital attenuator configured to attenuate the digital signal in response to a second control signal; and an attenuation controller configured to calculate average power and peak power of the attenuated digital signal, determine an attenuation value for each value of the calculated average power and peak power, and generate at least one of the first and second control signals based on the determined attenuation values.

Abstract: An interference cancellation repeater for canceling an interference signal included in an input signal including a first adaptive filter configured to generate a first estimated signal; a second adaptive filter configured to generate a second estimated signal; a first scaler configured to scale the first estimated signal based on a first scale factor determined according to a channel state; a second scaler configured to scale the second estimated signal based on a second scale factor determined according to the channel state; a first canceller configured to generate a first interference canceled signal based on the input signal and the scaled first estimated signal; and a second canceller configured to generate a second interference canceled signal based on the first interference canceled signal and the scaled second estimated signal.

Abstract: A repeater including an analog attenuator configured to attenuate an analog signal in response to a first control signal; an analog to digital converter (ADC) configured to convert the attenuated analog signal into a digital signal; a digital attenuator configured to attenuate the digital signal in response to a second control signal; and an attenuation controller configured to calculate average power and peak power of the attenuated digital signal, determine an attenuation value for each value of the calculated average power and peak power, and generate at least one of the first and second control signals based on the determined attenuation values.

Abstract: An interference cancellation repeater including a subtractor configured to subtract an estimated signal from a digital reception signal and output an interference canceled signal; a first power calculator configured to calculate power of the digital reception signal; a second power calculator configured to calculate power of the interference canceled signal; and an attenuation controller configured to compare a power value of the calculated digital reception signal with a power value of the calculated interference canceled signal and determine an attenuation value of the interference canceled signal according to the comparison result.