摘要:
Methods and apparatuses are provided for determining an interference transmission mode (TM) at a communication device in a cellular communication system using a resource element (RE) defined by frequency and time. A first signal is received in one RE. The first signal comprises a serving signal and an interference signal. A first vector of the received first signal is projected onto each of N projection vectors. A traffic-to-pilot ratio (TPR) decision metric of the interference signal is determined by using N pairs of an actual squared value and an expected squared value which are corresponding to the projected first vector. A TM of the interference signal is detected by determining a TF of the interference signal which minimizes the TPR decision metric from among predetermined transmit format (TF) candidates.
摘要:
A method and apparatus for transmitting at least two transport blocks in a Multi-Input Multi-Output (MIMO) communication system, in which a transmitter determines whether a type of a receiver receiving the at least two transport blocks is a Successive Interference Cancellation (SIC) receiver, determines a Modulation and Coding Scheme (MCS) level for the at least two transport blocks depending on whether the type of the receiver is an SIC receiver, and transmits the at least two transport blocks using the determined MCS level.
摘要:
An apparatus and method for generating a Channel Quality Indicator (CQI) in a wireless communication system are provided. The method includes receiving a Modulation and Coding Scheme (MCS) index and resource allocation information of a traffic channel and calculating a spectral efficiency at a particular time point, determining a temporary CQI index having a spectral efficiency closest to the calculated spectral efficiency in an index set, reading a CQI metric a time τ before the particular time point, determining, if the temporary CQI index is reported at the particular time point, an error rate based on the CQI metric, the error rate being a probability of an error occurring in a traffic channel after the time τ, receiving an error check result of the traffic channel transmitted at the particular time point and calculating a new error rate by applying a weight to the error check result and the error rate, and determining a CQI index to be fed back to a transmitter using the new error rate. Hence, the CQI index which maximizes spectral efficiency is determined and a Physical Downlink Shared CHannel (PDSCH) acknowledgement (ACK)/negative acknowledgement (NACK) probability is directly estimated adaptively according to a change in channel, thereby providing useful performance in various channel environments.
摘要:
An apparatus and method for reducing a Peak-to-Average Power Ratio (PAPR) are provided. The apparatus includes a gain processor for multiplying time signals in paths by gains set for respective paths, a delay processor for delaying gain-multiplied signals in second to last paths except for a first path by time delays set for respective second to last paths, a summer for summing the gain-multiplied signal for the first path received from the gain processor and the delayed signals received from the delay processor, a PAPR processor for measuring a PAPR of the summed signal received from the summer, for comparing the measured PAPR with a target PAPR, and for requesting one or more changes of at least one of the gain and time delay of each path, and a gain delay controller for changing the at least one of the gain and the time delay of each path according to the request received from the PAPR processor and for controlling the gain processor and the delay processor according to the change.
摘要:
A method and apparatus for reducing a Peak to Average Power Ratio (PAPR) using peak windowing is provided. In the apparatus, an absolute value calculator calculates an absolute value of an input signal, a subtractor subtracts a predetermined clipping threshold level from the absolute value, a smoothing unit performs smoothing on the subtracted signal according to a predetermined smoothing scheme and outputs a first smoothed signal, an adder adds the first smoothed signal to the clipping threshold level, an inverse calculator outputs a second smoothed signal by multiplying the clipping threshold level by an inverse of the added signal, and a multiplier outputs a final PAPR-reduced signal by multiplying the input signal by the second smoothed signal. The method and apparatus address an overcompensation problem while processing signals having a large bandwidth and a high data rate without delay, thereby minimizing the clipping influences on Bit Error Rate (BER) and Adjacent Channel Leakage Ratio (ACLR) performances.
摘要:
A method and apparatus for transmitting a signal in a Single Carrier-Frequency Division Multiplexing Access (SC-FDMA) communication system are provided. The method includes determining if a Bandwidth Expansion Factor (BEF) Q is an integer, the BEF being determined as N/M according to a number N of subcarriers of a system band and a number M of subcarriers of an allocated band, expanding an input signal to be transmitted Q times in a time domain when the Q is an integer, generating an SC-FDMA signal, and transmitting the SC-FDMA signal.
摘要:
A technique for avoiding reception performance deterioration caused by a tone interference that occurs at a position carrying a pilot signal in a wireless communication system is provided. A receiving end includes an operator for converting a time-axis signal into a frequency-axis signal, an extractor for generating channel values in positions carrying pilot signals among the frequency-axis signals, a compensator for compensating for a channel value of a position at which tone interference occurs by using at least one channel value of a position at which no tone interference occurs among the channel values.
摘要:
Methods, a Base Station (BS), and a User Equipment (UE) in a wireless communication system for transmitting and receiving control information are provided. The method for transmitting control information by a BS in a wireless communication system includes receiving information related to a signal transmitted by a second BS that the second BS which is a neighboring BS of the first BS, determining whether a second UE using an identical resource to that used by a first UE included in a cell of the first BS exists within a cell of the second BS based on the received information, when the second UE exists, generating control information for controlling a signal transmitted to the second UE by the second BS based on the received information, and transmitting the generated control information to the first UE through a control channel.
摘要:
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.