Abstract: A communication control apparatus and method of an artificial satellite are disclosed. The communication control apparatus includes a processor, a memory operatively connected to the processor, the memory being configured to store at least one piece of code to be executed by the processor, and a transmission and reception interface configured to communicate with a ground control center, wherein the memory stores code enabling the processor to receive location information of a signal generator on the ground from the ground control center, to calculate an angle of arrival for a target signal from the signal generator, received by the artificial satellite, based on the location information of the signal generator and location information of the ground control center, and to perform beamforming in a direction in which the artificial satellite detects the target signal based on the angle of arrival, when the code is executed by the processor.

Abstract: Provided are a method and apparatus for location estimation of terminals in a wireless communication system. A method of operating a positioning apparatus may include (a) calculating distances between a terminal and first, second, and third base stations, (b) creating first, second, and third circles centered at locations of the first, second, and third base stations with radii corresponding to the distances, (c) calculating intersection distances between two intersections formed by the second circle, which is the smallest circle, and one of the first circle and the third circle and the other two intersections formed by the first circle and the third circle, and (d) determining one of the intersections corresponding to the shortest distance among the intersection distances as the terminal's location.

Abstract: Provided are a method and apparatus for location estimation of terminals in a wireless communication system. A method of operating a positioning apparatus may include (a) calculating distances between a terminal and first, second, and third base stations, (b) creating first, second, and third circles centered at locations of the first, second, and third base stations with radii corresponding to the distances, (c) calculating intersection distances between two intersections formed by the second circle, which is the smallest circle, and one of the first circle and the third circle and the other two intersections formed by the first circle and the third circle, and (d) determining one of the intersections corresponding to the shortest distance among the intersection distances as the terminal's location.

Abstract: Disclosed is a GPS arrival angle selecting system. The system includes: a arrival angle estimating unit connected to a receiving antenna of a GPS receiver including at least one antenna array element and configured to decide a first arrival angle of a signal received prior to despreading and a second arrival angle of a signal received after despreading; and an arrival angle selecting unit configured to select a different peak value by comparing the first arrival angle and the second arrival angle. Also disclosed is a GPS arrival angle selecting method.

Abstract: Disclosed is a GPS arrival angle selecting system. The system includes: a arrival angle estimating unit connected to a receiving antenna of a GPS receiver including at least one antenna array element and configured to decide a first arrival angle of a signal received prior to despreading and a second arrival angle of a signal received after despreading; and an arrival angle selecting unit configured to select a different peak value by comparing the first arrival angle and the second arrival angle. Also disclosed is a GPS arrival angle selecting method.

Abstract: An apparatus and a method for canceling interference based on Maximum Likelihood (ML) at a receiver of a multi-antenna system are provided. The method includes estimating a channel using a signal received over one or more receiver antennas; generating one or more weights using the estimated channel to cancel interference; detecting a candidate symbol having the shortest Euclidean distance through Maximum Likelihood using a first weight; and soft-decoding the candidate symbol using a second weight. Therefore, by receiving the signal based on the ML under the interference, the system capacity can be increased and the reception performance can be enhanced.

Abstract: An apparatus and method for location estimation in a wireless communication system are provided. The method includes identifying if a received at least one signal passed through at least one repeater, when the received at least one signal is identified as having passed through at least one repeater, measuring a Base Station (BS) basis delay time and calculating a repeater basis delay time using the measured BS basis delay time, and estimating a location of the Mobile Station (MS) using the repeater basis delay time.

Abstract: A signal reception apparatus of an orthogonal frequency division multiplexing (OFDM) communication system using a multiple input, multiple output (MIMO) scheme. The signal reception apparatus, when it uses the NR receive antennas, receives a time-domain preamble signal transmitted by a signal transmission apparatus corresponding thereto via each of the NR receive antennas, and estimates a channel according to a channel estimation scheme using the time-domain preamble signal received via each of the NR receive antennas. When the signal transmission apparatus uses NT transmit antennas, the time-domain preamble signal is a signal transmitted by the signal transmission apparatus via each of the NT transmit antennas for a second time period which is set according to a corresponding transmit antenna within a first time period.

Abstract: An apparatus and method for location estimation in a wireless communication system are provided. The method includes identifying if a received at least one signal passed through at least one repeater, when the received at least one signal is identified as having passed though at least one repeater, measuring a Base Station (BS) basis delay time and calculating a repeater basis delay time using the measured BS basis delay time, and estimating a location of the MS using the repeater basis delay time.

Abstract: An apparatus and method for location estimation in a wireless communication system are provided. The method includes identifying if a received at least one signal passed through at least one repeater, when the received at least one signal is identified as having passed though at least one repeater, measuring a Base Station (BS) basis delay time and calculating a repeater basis delay time using the measured BS basis delay time, and estimating a location of the MS using the repeater basis delay time.

Abstract: The present invention relates to an apparatus and method for estimating a channel in a wireless communication system. The apparatus according to the present invention includes an estimator for initially estimating a channel response value by using a predetermined signal among reception signals, a detector for detecting transmission signals by using the channel response value and an operator for updating the channel response value by using detected transmission signals, a detection accuracy and reception signals.

Abstract: A method and an apparatus for estimating a location to support a location based service of a terminal in a mobile communication system are provided. The method includes receiving first reference signals from three base stations, calculating TDOAs, and solving a first equation using the TDOAs based on the first reference signals; when a solution of determining a location of a terminal based on the first equation is real or imaginary values, receiving second reference signals from the three base stations, calculating TDOAs, and solving a second equation using the TDOAs based on the second reference signals; and when a solution of determining the location of the terminal based on the second equation is real or imaginary values, determining the location of the terminal based on a relation between the first equation and the second equation.

Abstract: An apparatus and a method for canceling interference based on Maximum Likelihood (ML) at a receiver of a multi-antenna system are provided. The method includes estimating a channel using a signal received over one or more receiver antennas; generating one or more weights using the estimated channel to cancel interference; detecting a candidate symbol having the shortest Euclidean distance through Maximum Likelihood using a first weight; and soft-decoding the candidate symbol using a second weight. Therefore, by receiving the signal based on the ML under the interference, the system capacity can be increased and the reception performance can be enhanced.

Abstract: An apparatus and method for location estimation in a wireless communication system are provided. The method includes identifying if a received at least one signal passed through at least one repeater, when the received at least one signal is identified as having passed though at least one repeater, measuring a Base Station (BS) basis delay time and calculating a repeater basis delay time using the measured BS basis delay time, and estimating a location of the MS using the repeater basis delay time.

Abstract: The present invention relates to an apparatus and method for estimating a channel in a wireless communication system. The apparatus according to the present invention includes an estimator for initially estimating a channel response value by using a predetermined signal among reception signals, a detector for detecting transmission signals by using the channel response value and an operator for updating the channel response value by using detected transmission signals, a detection accuracy and reception signals.

Abstract: A signal reception apparatus of an orthogonal frequency division multiplexing (OFDM) communication system using a multiple input, multiple output (MIMO) scheme. The signal reception apparatus, when it uses the NR receive antennas, receives a time-domain preamble signal transmitted by a signal transmission apparatus corresponding thereto via each of the NR receive antennas, and estimates a channel according to a channel estimation scheme using the time-domain preamble signal received via each of the NR receive antennas. When the signal transmission apparatus uses NT transmit antennas, the time-domain preamble signal is a signal transmitted by the signal transmission apparatus via each of the NT transmit antennas for a second time period which is set according to a corresponding transmit antenna within a first time period.