Abstract:
PURPOSE: A distributed advance resource reservation method for blocking data collision in a wireless USB(Universal Storage Bus) network is provided to offer a new private DRP(Distribution and Replication Protocol) reservation method using a two-hop DRP availability IE. CONSTITUTION: A wireless USB host obtains MAR usage availability information from a specific wireless USB device. The wireless USB host collects three-hop range hidden private DRP reservation state information based on the obtained information. The wireless USB host selects a MAS slot which is not overlapped based on the collected reservation state information. The wireless USB host adds a beacon to a DRP IE by transmitting the DRP IE for a wireless USB channel to the wireless USB device.
Abstract:
본 발명은 TR-MUSIC 기반의 주파수 옵셋 추정 방법에 대하여 개시한다. 본 발명의 일면에 따른 TR-MUSIC 기반의 주파수 옵셋 추정 방법은, EEP 처리된 수신신호를 자기상관한 다음, TR-MUSIC 기법을 적용한 결과신호에 대칭되는 자기상관 행렬을 산출하는 단계; 상기 자기상관 행렬에 고유분해를 적용하여 신호 부분공간과 잡음 부분공간으로 분할하는 단계; 및 상기 신호 부분공간 및 상기 잡음 부분공간을 곱하여 산출된 주파수 스펙트럼에서 크기가 가장 큰 주파수를 주파수 옵셋으로 추정하는 단계를 포함하는 것을 특징으로 한다.
Abstract:
PURPOSE: A method for estimating an integer frequency offset by using the correlation of adjacent pilots in an OFDM(Orthogonal Frequency Division Multiplexing) system is provided to estimate an integer frequency offset by using the correlation of adjacent pilots in a frequency domain. CONSTITUTION: Fast Fourier transform(201) changes a received signal into a frequency domain signal. A symbol acquisition unit(202) obtains one or more consecutive OFDM(Orthogonal Frequency Division Multiplexing) symbols through a signal passing the fast Fourier transform. A plurality of received signal moving units(203) obtains a second frequency band by transferring a first frequency band of the OFDM symbol which is obtained according to a plurality of integer frequency offset candidate values. A template generating unit generates a template to maximize the correlation value between samples. A plurality of correlation units(205) calculates the correlation value between a sample and the template in the most adjacent pilot index. An integer frequency offset estimating unit(206) finally determines an integer frequency offset.
Abstract:
The present invention relates to a method for selecting a relay and setting power. More particularly, the present invention relates to a method for selecting a relay and setting power to obtain excellent performance. According to one embodiment of the present invention, the method for selecting a relay and setting power includes a step of settling a first and a second communication device by using a mathematical formula; and a step of setting the transmission power of the relay by a mathematical formula.
Abstract:
본 발명은 싸인 위상 이진 천이 반송 신호를 위한 코드 추적 방법에 관한 것으로서, 본 발명에 따른 코드 추적 방법은 BOC 신호의 자기상관함수를 구성하는 부상관함수들을 구하고 이를 모두 이용하여 주변 첨두가 완벽히 제거된 상관함수를 생성하며 생성된 상관함수를 다양한 형태의 판별기에 응용함으로써 신호를 신뢰성 있게 추적할 수 있다. 본 발명에 따르면, sine 위상 BOC 신호의 자기상관함수를 구성하는 부상관함수들을 모두 이용하여 주변 첨두가 완벽히 제거된 상관함수를 생성할 수 있고, 주변 첨두가 완벽히 제거된 상관함수의, 즉 BOC 신호의 자기상관함수와 같이, 폭이 좁은 주 첨두로 신뢰성 있는 코드 추적이 가능하다. 또한, 주변 첨두가 완벽히 제거된 상관함수를 DLL에 적용하여 신호를 신뢰성 있게 추적할 수 있고, 신뢰성 있는 신호 추적 기술을 통해 BOC 신호 동기화를 신뢰성 있게 구현할 수 있으며, 차세대 위성 항법 시스템의 거리 측정 오차를 줄일 수 있다.
Abstract:
PURPOSE: An OFDM[Orthogonal Frequency Division Multiplexing] frequency offset estimating method based on the combination of continuous correlation values is provided to obtain a correlation value which is nearly constant regardless of a time error value. CONSTITUTION: The components of a differentially combined result are added. A time error which maximizes the added value of components is calculated. The added value of the components is calculated in a state where the time error is nonexistent. [Reference numerals] (AA) Normalized correlation value; (BB) Time error(τ)
Abstract:
PURPOSE: A synchronization improvement method of a marine telematics Galileo satellite system is provided to solve a plurality of peak problems of AltBOC(alternative binary offset carrier) signals and CBOC(composite BOC) signals. CONSTITUTION: A unit pulse signal S0alt, S2alt, ···,S2k-1alt is defined to indicate an AltBOC(kn, n) signal subcarrier in a half period. A correlation function of the defined unit pulse signal and AltBOC(1.5n, n) signals are indicated as R0alt, R2alt, ···,R2k-1alt and by reuniting a sum total of the correlation functions according to an equation, the correlating function removing a peripheral peak. [Reference numerals] (AA) AltBOC subcarrier; (BB) Pseudo noise code chip time; (CC,DD,EE,FF) Time