Abstract:
PURPOSE: A frequency offset estimation apparatus in an orthogonal frequency division multiplexing system is provided to estimate a frequency offset by considering non-uniform impulsive noise, thereby improving frequency offset estimation performance in a non-uniform impulsive noise environment. CONSTITUTION: A frequency offset estimation apparatus estimates a frequency offset using one training symbol including two symbols with the same structure and value. A first likelihood function output part models non-uniform impulsive noise included in the training symbol into a Cauchy probability density function. The first likelihood function output part outputs a likelihood function of Cauchy distribution using the Cauchy probability density function. A first frequency offset estimation part estimates a frequency offset operation value maximizing the likelihood function of the Cauchy distribution in the first likelihood function output part. The first likelihood function output part models the non-uniform impulsive noise using symmetric alpha stability distribution into a two-variable isotropic symmetric alpha-stability probability density function.
Abstract:
본 발명은 다중 경로 채널 환경에서 DM-BPSK 변조 방식을 사용한 CSS 시스템의 성능 분석 방법에 관한 것으로서, 본 발명에 따른 방법은 상기 CSS 시스템에서 채널을 통과하여 레이크 수신기에서 수신된 수신 신호를 모델링하는 제1 단계, 상기 모델링된 수신 신호를 입력으로 사용하는 상관기의 출력을 모형화하는 제2 단계, 상기 상관기의 출력을 입력으로 사용하는 최대 비율 결합기의 출력으로부터 송신 신호에 대한 결정 변수를 산출하는 제3 단계, 상기 결정 변수를 이용해서 채널당 평균 SINR(신호 대 간섭과 잡음비)을 산출하는 제4 단계, 채널당 평균 SINR을 이용해서 교차 상관 계수를 산출하여 상기 CSS 시스템의 비트오류율을 유도하는 제5 단계를 포함한다.
Abstract:
PURPOSE: An apparatus for frequency estimation at a OFDM system and a method thereof are provided to magnify frequency offset range by using a signal of period diagram in rayleigh fading channel environment. CONSTITUTION: An envelope curve regulating process of component generating unit(200) generates a component of envelop equality process. A integer frequency offset estimator(300) gets the fixed number frequency offset estimation value in which the sum between the consecutive period diagram makes have the maximum value. The prime number frequency offset estimator(400) gets the fraction frequency offset estimation value from the phase difference of the consecutive period diagram. The remainder frequency offset estimator(500) gets the frequency offset by using the fixed number frequency offset presumed and the period diagram corresponding to the fraction frequency offset.
Abstract:
A method for estimating OFDM frequency offset based on a partial periodogram according to the present invention includes the steps of: (a) performing envelope equalized processing (EEP) as to an OFDM receiving signal; (b) estimating initial offset as to the EEP-processed receiving signal; and (c) estimating precise offset repetitively using the initial offset and the partial periodogram. Furthermore, the method may include the step of (d) estimating residual offset repetitively to estimate possible offset after the precise offset estimation. Through this, the method of the present invention can perform reliable frequency offset estimation as having low computation.
Abstract:
A method for generating a CBOC correlation function comprises a step of receiving a CBOC signal (500) by a receiving means; a step of calculating a partial correlation function (501) by using the CBOC signal and a plurality of local signals by a calculating means; and a step of integrating the partial correlation function (502) to generate the CBOC correlation function with removed neighborhood peaks by the calculating means.
Abstract:
The present invention discloses a binary offset carrier (BOC) signal synchronization device, a method thereof, a simulation device for BOC signal synchronization, and a simulation method thereof. The simulation device for BOC signal synchronization, given in the present invention, includes a transmitting unit which generates a BOC signal by combining a pseudo random noise signal and a sub-carrier and transmits the BOC signal to a receiving unit; and the receiving unit which receives the BOC signal, generates multiple negative correlation functions using the correlation between the received BOC signal and a sub-BOC signal generated as a local signal, generates the final correlation function from which surrounding peaks are removed by recombining the generated negative correlation functions, and performs synchronization. If the synchronization fails, the receiving unit updates the phase of the sub-BOC signal and repeats the process of generating the final correlation function described above. [Reference numerals] (100) Transmitting unit;(110) PRN signal generating unit;(120) Sub-carrier generating unit;(200) Receiving unit;(210) Negative correlation function generating unit;(220) Final correlation function generating unit;(230) Synchronization determining unit;(240) Phase update unit;(AA) BOC signal
Abstract:
무선 통신 시스템에서 주파수 오프셋(offset) 추정 방법 및 장치를 제공한다. 상기 방법은 N개의 샘플로 구성되는 수신 신호를 입력 받는 단계; 상기 수신 신호에서 N/2개의 샘플을 구하는 단계; 상기 N/2개의 샘플을 합하는 단계; 상기 N/2개의 샘플을 합한 신호에서 각도를 구하는 단계; 및 상기 구한 각도를 기반으로 주파수 오프셋 추정치를 구하는 단계를 포함하는 것을 특징으로 한다.