Electronics and Telecommunications Research Institute

Samsung Electronics Co., Ltd.

Hyeong Sook Park

Youn Ok Park

Jun-Woo Kim

Young Jo Bang

Kyung Yeol Sohn

Jun Woo Kim

Hoon Ki Lee

Seung Jae Bahng

Chang Wahn Yu

Jae Kwon Kim

Eon Young Hong

Youn-Ok Park

Hoon Do Heo

Dae Ho Kim

Jee Hwan Ahn

Jung Pil Choi

Seungjae Bahng

Young Ha Lee

Yong Su Lee

Il Min Kim

Hyun Myung Wu

Dong Weon Yoon

Kwang Min Hyun

A method for transmitting a PTRS by a transmitting node may include: identifying a time density and a frequency density of PTRS; identifying a first offset based on the frequency density of PTRS and a second offset based on N times the frequency density of PTRS, N being an integer equal to or greater than 2; determining a position of a subcarrier to transmit a first PTRS and a position of a subcarrier to transmit a second PTRS using the first offset and the second offset; determining a resource block (RB) to transmit each of the first PTRS and the second PTRS from resources allocated to a receiving node; configuring a data channel including data, demodulation reference signals (DMRSs) for demodulation of the data, the first PTRS, and the second PTRS; and transmitting the data channel to the receiving node.

Method and apparatus for estimating phase noise in communication system

An operation method of a receiving apparatus may comprise: receiving an N-th data block belonging to a frame including a plurality of data blocks from a transmitting apparatus, each of the plurality of data blocks including a data period and a UW period; storing a first UW received in a UW period of the N-th data block in a buffer; receiving an (N+1)-th data block belonging to the frame from the transmitting apparatus; estimating a phase noise in a time domain by combining the first UW with a second UW received in a UW period of the (N+1)-th data block; and applying time-domain compensation according to the estimated phase noise to the (N+1)-th data block, and demodulating data of the (N+1)-th data block, wherein the first UW and the second UW are configured with a same sequence.

Transceiving method for phase noise compensation in SC-FDE scheme, and apparatus therefor

The exemplary embodiment of the present invention provides a beam selecting apparatus of a fixed beam terminal, including: a delay time measuring unit which measures delay times of a plurality of signals received through a plurality of beams; a beam selecting unit which compares a threshold value selected based on the measured delay time and a signal strength of each of the plurality of signals to select a beam; and a switching type beam former which operates the plurality of beams in accordance with the selected beam.

Beam selection apparatus and method for selecting beam in a fixed beam terminal

The present invention relates to a data transmitting method using a bandwidth request channel and a user terminal and a base station conducting the same. The present invention provides a communication method by a user terminal which transmits data to a base station via a bandwidth request channel, including: generating a preamble for bandwidth request; determining whether a message for the bandwidth request is generated; generating a first signal value to be operated with the preamble when it is determined that the message is generated and generating a second signal value to be operated with the preamble when it is determined that the message is not generated; operating the preamble with the generated first signal value or second signal value; and transmitting a signal including the operated preamble to the base station, thereby reducing overhead occurring when the bandwidth request information is demodulated.

Method for communicating data using bandwidth request channel, user equipment and base station conducting the same

There is provided a method for acquiring and modifying uplink and downlink synchronization, by which, if there is a possibility of ISI occurring due to incorrect downlink synchronization of a terminal with a base station, the terminal receives a ranging response from the base station, modifies incorrect downlink synchronization, and acquires uplink synchronization in accordance with modified downlink synchronization. The method for acquiring and modifying uplink and downlink synchronization efficiently prevents, in a cooperative communication network, discrepancy in signal transmission synchronization between the base stations, excessive attenuation of a transmitted signal, or a delay caused by a difference in reflection paths.

Method and apparatus for acquiring uplink and downlink synchronization between a plurality of base stations and a terminal in a cooperative communication network

A data processing method, an equalizer, and a receiver in a wireless communication system including a relay station are provided. The data processing method includes: receiving a base station signal from a base station; receiving a relay station signal from a relay station; determining a propagation delay between the base station signal and the relay station signal; generating an equalizing signal in which interference generated between the base station signal and the relay station signal is alleviated in consideration of the propagation delay; and recovering information bits transmitted by the base station from the equalizing signal. According to an exemplary embodiment of the present invention, it is possible to alleviate performance deterioration due to an interference problem generated in a relay system.

Data processing method, equalizer and receiver

There is provided a method and apparatus for estimating a signal to noise ratio (SNR) in a wireless communication system. The apparatus selects a preamble signal for each of a plurality of sectors from a reception signal experienced by fast Fourier transform (FFT), outputs a correlation signal by performing a correlation between the preamble signal for each sector and a preamble reference signal, estimates power of the reception signal and noise power for each sector based on the correlation signal, selects a minimum value from among the noise powers for the sectors, outputs a net power for each sector by subtracting the minimum value from the power of the reception signal for each sector, and calculates the SNR by dividing the net power for each sector by the minimum value.

Method and apparatus for estimating signal to noise ratio in wireless communication system

Disclosed is a method and apparatus for composing a received symbol signal modulated with a bit reflected Gray code into bit information. According to an embodiment of the present invention, a positive integer of the received symbol signal having bits is assigned according to the Gray mapping rule, and a sign is determined. A value that is indicative of an arrangement of the bits constituting the received symbol signal is calculated. A boundary value in at least one bit group consisting of the bits constituting the received symbol signal is acquired, and a difference from an absolute value of the received symbol signal is calculated. The received symbol signal is converted into information per bit using a value of the received symbol signal based on the positive integer and the determined sign, the value that is indicative of the bit arrangement, and the difference from the absolute value. Therefore, it is possible to reduce complexity in bitwise decomposition for an iterative decoder inevitably used in a receiver.

Method and apparatus for decomposing received symbol signal modulated with bit reflected gray code in bit information

Disclosed is a method of detecting signals at a receiver of a communication system with a multiple input multiple output antenna. With the signal detection method, a square of the distance between a received signal vector and a channel status-considered transmission symbol vector is calculated first, and the square of the distance is then classified into first and second components. The first component is minimized to calculate a plurality of first soft symbol estimates. A solution set of the first component is calculated on the basis of the plurality of first soft symbol estimates. The second component is minimized to calculate a plurality of second soft symbol estimates. A solution set of the second component is calculated on the basis of the plurality of second soft symbol estimates. A final solution set is calculated by doing the sum of the first component solution set and the second component solution.

Signal detection method and receiver

The present invention relates an apparatus and method of estimating a signal-to-noise ratio (SNR) of a received signal when the received signal has a timing offset. An apparatus for estimating a signal-to-noise ratio (SNR) according to an exemplary embodiment of the present invention includes a fast Fourier transform (FFT) unit that performs a fast Fourier transform on a received signal to convert the received signal into a frequency domain signal; a preamble selector that extracts a preamble from the frequency domain signal; a correlator that correlates the preamble to a preamble reference signal generated by a receiver to calculate a correlation value; an entire power estimator that calculates entire power; a noise power estimator that applies a differential demodulation method to the correlation value to remove a timing offset and calculate noise power; and an estimating unit that uses the entire power and the noise power to estimate the signal-to-noise ratio (SNR).

Apparatus and method of estimating signal-to-noise ratio

The present invention relates to a method of detecting a candidate vector and a method of detecting a transmission symbol using the same. According to an embodiment of the present invention, in a multiple input multiple output (MIMO) system using spatial multiplexing (SM), a receiver selects candidate vectors corresponding to a layer located at a last row among a plurality of rearranged layers, and sequentially ranks constellation dots of a next layer for each of the selected candidate vectors. Then, a plurality of arbitrary constellation dots are selected from the ranked constellation dots, accumulated costs of the arbitrary constellation dots are calculated, and a candidate vector is selected in correspondence with a constellation dot having a minimal accumulated cost. Then, a new arbitrary constellation dot is selected in place of the constellation dot selected as the candidate vector, an accumulated cost of the selected arbitrary constellation dot is compared with accumulated costs of the other arbitrary constellation dots, and another candidate vector is selected.

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Daejeon, South Korea

Hyeong Sook Park