Abstract:
본 발명은 통신 시스템에서 신호 대 간섭 및 잡음비 추정 방법에 관한 것으로, 트래픽 신호를 할당할 수 있는 영역인 트래픽 할당 가능 영역과 상기 트래픽 할당 가능 영역 내에 프리엠블 신호를 할당할 수 있는 프리엠블 할당 가능 영역을 포함하며, 상기 프리엠블 할당 가능 영역 내에 프리엠블 신호를 포함하는 OFDM(Orthogonal Frequency Division Multiplexing) 심볼을 고속 푸리에 변환(FFT: Fast Fourier Transform)하고, 상기 FFT된 OFDM 심볼에 포함된 프리엠블 신호들의 전력값들을 계산하고, 계산된 전력값들을 이용하여 반송파 전력값을 계산하며, 상기 FFT된 OFDM 심볼에 포함된 상기 프리엠블 신호들간의 전력 차이값들과 상기 프리엠블 신호들을 제외한 신호들의 전력값들을 이용하여 잡음-간섭 전력값을 계산하며, 상기 FFT된 OFDM 심볼에 포함된 상기 트래픽 할당 가능 영역에서 상기 프리엠블 할당 가능 영역을 제외한 영역인 잡음 전력 추정 영역에 포함된 신호들의 전력값들을 이용하여 잡음 전력값을 계산하고, 상기 반송파 전력값과 상기 잡음-간섭 전력값과 상기 잡음 전력값을 이용하여 상기 신호 대 간섭 및 잡음비를 계산한다. 직교 주파수 분할 다중 액세스 방식(OFDMA: Orthogonal Frequency Division Multiple Access), 신호 대 간섭 및 잡음비(CINR: Carrier to Interference and Noise Ratio), 프리엠블(preamble)
Abstract:
An apparatus and a method for allocating a preamble index to a self configurable base station in a broadband wireless communication system are provided to enable a user to select a permeable index having the lowest mutual interference by allocating a permeable index based on RSSI(Received Signal Strength Indication) and the position information of base stations. An SC-management server selects the FA(Frequency Allocation) having the minimum sum of RSSI as the FA of an SC-base station(603). The SC-management server selects the segment ID having the minimum RSSI as the segment ID of an SC-controller(605). The SC-management server selects the ID cells, which are allocated to a base station having the maximum value related to the minimum distance, as the ID cell of the SC-base station(611). The SC-management server transmits the selected FA and the permeable index information to the SC-base station(613).
Abstract:
A power control apparatus and a method thereof in a wireless communications system are provided to reduce interference reaching a large sized base station from a small sized based station. A duplexer(300) transmits reception signal to a reception modem(310) from an antenna according to time division duplex method. A transmission signal is transmitted from a transmission modem(360) to the antenna. Data is restored from the signal which is provided from the duplexer and delivered to a controller(320). A receive power detector(330) is provided from the reception modem with the signal received from neighboring outdoor base stations. The reception power is measured and provided to the power controller(340). The controller receives transmission data from the high layer.
Abstract:
An apparatus and a method for measuring a carrier to interference and noise ratio in a communication system are provided to measure the carrier to interference and noise ratio in a multi path environment by calculating the noise-interference power value and a noise power value without an effect of the multiple path environment. An OFDM symbol is fast Fourier transformed. The OFDM symbol includes a traffic assignment domain to assign the traffic signal, a preamble assignment domain to assign the preamble signal in the traffic assignment domain, and the preamble signal in the preamble assignment domain(500). A carrier power value is calculated by calculating the power values of the preamble signals included in the fast Fourier transformed OFDM symbol and using the calculated value(502). The noise-interference power value is calculated by usingg the power difference values between the preamble signals included in the fast Fourier transformed OFDM, and the power value of the signals except the preamble signals(504). The noise power value is calculated by using the power values of the signals included in the noise power estimation domain except the preamble assignment domain in the traffic assignment domain included in the fast Fourier transformed OFDM symbols(506). The carrier to interference and noise ratio is calculated by using the carrier power value, the noise-interference power value and the noise power value(508).
Abstract:
A method for determining a transfer rate in a communication system is provided to allocate an exact MCS(Modulation and Coding Scheme) level to mobile stations by receiving the channel states reported from mobile terminals, adding an interference level to the values of the reported channel states on the basis of a previously stored interference level table based on the number of mobile stations, and determining an MCS level. A base station transmits reference signals, such as preamble signals, to mobile stations(202). Then the base station receives CQI(Channel Quality Information) from mobile stations and demodulates it(204). The base station executes scheduling and determines the number of mobile stations to which data are to be transmitted(206). The base station selects an interference level equivalent to the determined number from a previously stored interference level table based on the number of mobile stations(208). The base station determines a CINR(Carrier to Interference and Noise) in consideration of the selected interference level and allocates an MCS level according to the determined CINR(210).
Abstract:
PURPOSE: A photonic-crystal optical fiber coupler and a method for manufacturing the same are provided to have a light distribution or a wavelength divisional function of a conventional single mode optical fiber coupler as well as to divide the optical signal into at least two optical fiber with a constant ratio. CONSTITUTION: A photonic-crystal optical fiber coupler includes at least two photonic-crystal optical fibers(10,20) and at least one coupling region(30). Each of the photonic-crystal optical fibers(10,20) includes a core part and a clad part provided with a plurality of holes with encompassing the core part. And, the coupling region(30) is formed along the longitudinal direction of the photonic-crystal optical fibers(10,20).
Abstract:
PURPOSE: A photonic-crystal optical fiber coupler and a method for manufacturing the same are provided to have a light distribution or a wavelength divisional function of a conventional single mode optical fiber coupler as well as to divide the optical signal into at least two optical fiber with a constant ratio. CONSTITUTION: A photonic-crystal optical fiber coupler includes at least two photonic-crystal optical fibers(10,20) and at least one coupling region(30). Each of the photonic-crystal optical fibers(10,20) includes a core part and a clad part provided with a plurality of holes with encompassing the core part. And, the coupling region(30) is formed along the longitudinal direction of the photonic-crystal optical fibers(10,20).