A method and apparatus for estimating a channel in a wireless local area network (WLAN) are provided. A channel estimation apparatus may include a channel estimation information combiner to combine at least one channel estimation information based on a difference between cyclic delay diversity (CDD) values, and a phase applier to generate a first phase value and to apply the first phase value to the combined channel estimation information.

A power feed circuit for feeding power to first through fifth antenna elements sequentially arranged in a horizontal direction includes a 90-degree hybrid circuit including two input terminals and two output terminals, an equal distribution circuit that the power-feed signal output from one of the output terminals is equally distributed and output to the second and fourth antenna elements, and a distribution circuit that power-feed signal output from the other of the output terminals is distributed and output to the first, third and fifth antenna elements. The distribution circuit distributes such that electrical power output to the first and fifth antenna elements is equal and that a sum of electrical power output to the first and fifth antenna elements is not more than that output to the third antenna element. A phase-inverted power is fed to the third antenna element and either one of the second and fourth antenna elements.

A transmission method includes generating a first precoded signal and a second precoded signal by performing a precoding process on a first baseband signal and a second baseband signal, outputting a third signal by inserting a pilot signal into the first precoded signal, outputting a fourth signal by applying a first phase change to the second precoded signal, outputting a fifth signal by inserting a pilot signal into the fourth signal, and outputting a sixth signal by applying a second phase change to the fifth signal.

A transmission apparatus includes a plurality of orthogonal frequency division multiplexing (OFDM) modulation signal generators, which generate a first OFDM modulation signal and a second OFDM modulation signal. The transmission apparatus also includes a transmitter that transmits the first OFDM modulation signal from a first antenna and the second OFDM modulation signal from a second antenna, in an identical frequency band. A reception apparatus is provided, which includes a plurality of antennas that receive a plurality of OFDM modulation signals; a plurality of OFDM demodulators that transform the plurality of OFDM modulation signals to a plurality of reception signals using Fourier transform; an estimator that outputs a distortion estimation signal using one or more symbols for demodulation included in the plurality of reception signals; and a demodulator that compensates for distortion of the reception signals using the distortion estimation signal and demodulates a data symbol included in the reception signals.

Various embodiments are described that relate to radio beamforming waveform transmission. Transmission can occur, for example, in three manners. The first manner is time-based where waveform transmission is staggered at the same frequency. The second manner is frequency-based where different frequencies are used at one time. This third manner is a combination of time and frequency such that simultaneous transmission occurs, but at different times different frequencies are used.

A plurality of modulation signals is generated. Each of the plurality of modulation signals includes a pilot symbol sequence having a plurality of pilot symbols. Each pilot symbol sequence is inserted at a same temporal point in each modulation signal, and each pilot symbol in the pilot symbol sequence has a non-zero amplitude. A quantity of the plurality of pilot symbols in each pilot symbol sequence is greater than or equal to a quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals are transmitted in an identical frequency band from a plurality of antennas. Each of the transmitted plurality of modulation signals includes transmission data and one of the pilot symbol sequences.

A method, an apparatus, and a computer-readable medium for wireless communication are provided. In one aspect, an apparatus includes a processor configured to determine a first set of CSD values for transmitting a first set of information on a plurality of antennas, determine a second set of CSD values for transmitting a second set of information on the plurality of antennas, and transmit the first set of information based on the first set of CSD values and the second set of information based on the second set of CSD values.

A circular stapling instrument is provided. The circular stapling instrument includes a handle forming a cavity, a reciprocating drive shaft, a carrier cover, and a shaft assembly. The reciprocating drive shaft is detachably secured within the cavity of the handle. The carrier cover covers a portion of the reciprocating drive shaft within the cavity of the handle. The shaft assembly is detachably coupled with the handle.

Provided is a receiver device that can switch between transmission methods, while minimizing increase in the number of blind decryption iterations and the amount of signaling needed for acknowledgement. In this device, a receiver part (201) receives a signal mapped to any of a plurality of mapping candidates; and according to application levels established for each of the plurality of mapping candidates, a control signal processor (205) performs blind decryption of the plurality of mapping candidates, employing either a first transmission method using a single antenna port to carry out precoding based on feedback information from the receiver device, or a second transmission method involving transmission diversity employing multiple antenna ports.

The present invention relates to a method by which a base station transmits a reference signal in a wireless communication system supporting a full-dimension antenna, and a device for the same. Particularly, the method comprises the steps of: transmitting, to a terminal, a channel state information-reference signal (CSI-RS) configuration indicating the number of antenna ports for transmitting a full-dimension antenna association reference signal; transmitting, to the terminal, a CSI-RS for at least one first antenna port among whole antenna ports for the full-dimension antenna; and receiving, from the terminal, channel information on all of the antenna ports on the basis of the at least one first antenna port.