Abstract: A method of uplink power control including generating a transmission power control (TPC) sequence from TPC commands received on a series of slots, the series of slots forming one radio frame, calculating a plurality of correlation results by executing correlation calculations between the TPC sequence and a plurality of command sequences, and determining an overall TPC command based on the plurality of correlation results may be provided.

Abstract: Methods and apparatuses are provided for performing a cell search by a receiver in a communication system. A scrambling code is identified by correlating a common pilot channel with a first synchronization accumulation length based on a frame boundary and a code group. A multipath signal is sought by correlating the common pilot channel with a second synchronization accumulation length based on the frame boundary and the code group. A difference between, or a ratio of, a first maximum value of first correlation values acquired during identification of the scrambling code and a second maximum value of second correlation values acquired during searching for the multipath signal, is determined. It is determined whether a frequency offset exists by comparing the difference or the ratio with a predetermined threshold value. The frequency offset is estimated and the frequency offset is transmitted to a demodulator, when the frequency offset exists.

Abstract: A method of uplink power control including generating a transmission power control (TPC) sequence from TPC commands received on a series of slots, the series of slots forming one radio frame, calculating a plurality of correlation results by executing correlation calculations between the TPC sequence and a plurality of command sequences, and determining an overall TPC command based on the plurality of correlation results may be provided.

Abstract: A method and an apparatus for measuring a link quality in a wireless communication are provided. The method of a receiver for measuring the link quality in the wireless communication system includes determining a modulation type for each of at least one reception stream received through at least one antenna based on a modulation order and channel information regarding each of signals transmitted from a plurality of transmission antennas, searching for a parameter corresponding to the determined modulation type from a pre-stored parameter table in which parameters for each modulation type are stored, and calculating a channel capacity for each of the at least one reception streams received through the at least one antenna by using the searched parameter.

Abstract: A method of detecting indicator information received by a receiver of a wireless communication system is provided, and the method includes determining a threshold value that reduces costs incurred by a false alarm rate that decides discontinuous transmission (DTX) information transmitted from a transmitter as non-DTX information and a missed detection rate that decides non-DTX information transmitted from the transmitter as DTX information; and detecting the indicator information using the threshold value. The threshold value is determined based on a reception quality level for acknowledgement (ACK) information when the transmitter transmits the ACK information.

Abstract: A method and an apparatus for measuring channel quality in a MIMO system is provided. The method includes measuring a first SINR based on an assumption that a first detector is used, using a channel estimation value of a reception signal with respect to each of a plurality of space layers, and a second SINR for each of the plurality of space layers corresponding to a case where the plurality of space layers exist independently using the channel estimation value of the reception signal; determining a Log Likelihood Ratio of reception data based on an assumption that a second detector is used, with respect to each of the plurality of space layers; and generating channel quality information based on an assumption that the second detector is used, based on the first SINR and the second SINR with respect to each of the plurality of space layers, and the LLR.

Abstract: A communication device and method of controlling the same are provided. A communication device includes a transceiver that receives a radio signal and a processor electrically connected to the transceiver, and is configured to store a data signal including data received through the radio signal in a first buffer according to a first delay period, store a channel signal including channel estimation information on a transmission channel of the radio signal in a second buffer according to a second delay period, determines a coefficient of a low pass filter and a group delay related to the low pass filter based on information related to the radio signal, and output at least one of the channel signals stored in the second buffer based on the determined group delay and the first delay period to perform equalizing.

Abstract: Methods and apparatuses are provided for reducing power consumption by early decoding. It is determined whether a predetermined decoding condition is satisfied upon expiration of a time unit in a transmission time interval. Decoding is performed on a signal that has been received through the time unit in the transmission time interval, when the predetermined decoding condition is satisfied. A controller outputs an instruction signal to a RF processor to set to a low-power mode during a remaining time period of the transmission time interval after the time unit in the transmission time interval, when the decoding is successful. Decoding is performed on the signal that has been received through the RF processor upon expiration of a last time unit of the transmission time interval regardless of the predetermined decoding condition, when the time unit is the last time unit in the transmission time interval.

Abstract: A terminal including a transmitter and a receiver is provided. The receiver includes a pilot detection unit configured to detect a pilot signal from a received signal; a low-pass filter configured to filter noise from the pilot signal; a channel equalizer configured to perform channel equalization for data of the received signal, based on the filtered pilot signal; and a channel estimation controller configured to adaptively adjust at least one of a coefficient and an order of the low-pass filter, wherein the coefficient of the low-pass filter is controlled according to characteristics of the pilot signal, and the order of the low-pass filter is controlled according to transmission characteristics of the data of the received signal.

Abstract: A communication device and method of controlling the same are provided. A communication device includes a transceiver that receives a radio signal and a processor electrically connected to the transceiver, and is configured to store a data signal including data received through the radio signal in a first buffer according to a first delay period, store a channel signal including channel estimation information on a transmission channel of the radio signal in a second buffer according to a second delay period, determines a coefficient of a low pass filter and a group delay related to the low pass filter based on information related to the radio signal, and output at least one of the channel signals stored in the second buffer based on the determined group delay and the first delay period to perform equalizing.

Abstract: Methods and apparatuses are provided for performing a cell search by a receiver in a communication system. A scrambling code is identified by correlating a common pilot channel with a first synchronization accumulation length based on a frame boundary and a code group. A multipath signal is sought by correlating the common pilot channel with a second synchronization accumulation length based on the frame boundary and the code group. A difference between, or a ratio of, a first maximum value of first correlation values acquired during identification of the scrambling code and a second maximum value of second correlation values acquired during searching for the multipath signal, is determined. It is determined whether a frequency offset exists by comparing the difference or the ratio with a predetermined threshold value. The frequency offset is estimated and the frequency offset is transmitted to a demodulator, when the frequency offset exists.

Abstract: A method and an apparatus for measuring channel quality in a MIMO system is provided. The method includes measuring a first SINR based on an assumption that a first detector is used, using a channel estimation value of a reception signal with respect to each of a plurality of space layers, and a second SINR for each of the plurality of space layers corresponding to a case where the plurality of space layers exist independently using the channel estimation value of the reception signal; determining a Log Likelihood Ratio of reception data based on an assumption that a second detector is used, with respect to each of the plurality of space layers; and generating channel quality information based on an assumption that the second detector is used, based on the first SINR and the second SINR with respect to each of the plurality of space layers, and the LLR.

Abstract: A terminal including a transmitter and a receiver is provided. The receiver includes a pilot detection unit configured to detect a pilot signal from a received signal; a low-pass filter configured to filter noise from the pilot signal; a channel equalizer configured to perform channel equalization for data of the received signal, based on the filtered pilot signal; and a channel estimation controller configured to adaptively adjust at least one of a coefficient and an order of the low-pass filter, wherein the coefficient of the low-pass filter is controlled according to characteristics of the pilot signal, and the order of the low-pass filter is controlled according to transmission characteristics of the data of the received signal.

Abstract: A method of detecting indicator information received by a receiver of a wireless communication system is provided, and the method includes determining a threshold value that reduces costs incurred by a false alarm rate that decides discontinuous transmission (DTX) information transmitted from a transmitter as non-DTX information and a missed detection rate that decides non-DTX information transmitted from the transmitter as DTX information; and detecting the indicator information using the threshold value. The threshold value is determined based on a reception quality level for acknowledgement (ACK) information when the transmitter transmits the ACK information.

Abstract: Methods and apparatuses are provided for reducing power consumption by early decoding. It is determined whether a predetermined decoding condition is satisfied upon expiration of a time unit in a transmission time interval. Decoding is performed on a signal that has been received through the time unit in the transmission time interval, when the predetermined decoding condition is satisfied. A controller outputs an instruction signal to a RF processor to set to a low-power mode during a remaining time period of the transmission time interval after the time unit in the transmission time interval, when the decoding is successful. Decoding is performed on the signal that has been received through the RF processor upon expiration of a last time unit of the transmission time interval regardless of the predetermined decoding condition, when the time unit is the last time unit in the transmission time interval.

Abstract: A method and an apparatus for measuring a link quality in a wireless communication are provided. The method of a receiver for measuring the link quality in the wireless communication system includes determining a modulation type for each of at least one reception stream received through at least one antenna based on a modulation order and channel information regarding each of signals transmitted from a plurality of transmission antennas, searching for a parameter corresponding to the determined modulation type from a pre-stored parameter table in which parameters for each modulation type are stored, and calculating a channel capacity for each of the at least one reception streams received through the at least one antenna by using the searched parameter.

Abstract: An automatic gain control apparatus and method for a compressed mode in a MIMO system are provided. The method includes determining power at a first frequency band using a first receiver, simultaneously determining power at a second frequency band using a second receiver in a compressed mode, if the second receiver changes a power determination frequency band into the first frequency band, correcting the power determination value of the first receiver, and applying the corrected power determination value of the first receiver to the second receiver.

Abstract: An apparatus and a method for selecting a receiver for demodulating a reception signal at a reception end having a plurality of receivers are provided. The method includes determining, a mean and a standard deviation of Signal-to-Noise Ratios (SNRs) of the receivers are determined, estimating a Doppler frequency, determining a statistical value of a modulation order of subframes received in advance, determining SNR estimation values of the receivers based on the determined mean and standard deviation of the receivers, the estimated Doppler frequency, and the determined statistical value of the modulation order of the received subframes, selecting one receiver having a largest SNR estimation value among the determined SNRs of the receivers, and demodulating a reception signal using the selected receiver.

Abstract: A mobile terminal includes a channel estimation module that is maintained in an active state. A controller determines an activation time point of an equalizer weight calculation module for calculating a tap coefficient. The activation time point is earlier than an activation time point of a main equalizer module, and activates the equalizer weight calculation module at the activation time point so as to calculate the tap coefficient. When the equalizer weight calculation module's operation is completed, the controller activates the main equalizer module, detects a mobile terminal ID, activates an interference cancellation module, and controls the main equalizer module to provide a data signal demodulator with the data signal compensated for by the tap coefficient. A demodulator demodulates the compensated data signal.

Abstract: An apparatus and a method for selecting an operation mode to improve a throughput in a mobile communication system are provided. The apparatus includes a Carrier to Interference and Noise Ratio (CINR) predictor for predicting a probable average and dispersion for a CINR measured using a preamble of a received pilot signal or radio signal, a metric calculator for calculating a throughput for each Modulation and Coding Scheme Level (MCS_Level) by using the probable average and dispersion for the predicted CINR and for selecting an MCS_Level having a maximum throughput, and an operation mode selector for selecting an operation mode of the selected MCS_Level having the maximum throughput.