• Title/Summary/Keyword: Correlation Interference

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A correlation-based analysis on wind-induced interference effects between two tall buildings

  • Xie, Z.N.;Gu, M.
    • Wind and Structures
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    • v.8 no.3
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    • pp.163-178
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    • 2005
  • Wind-induced mean and dynamic interference effects of tall buildings are studied in detail by a series of wind tunnel tests in this paper. Interference excitations of several types of upwind structures of different sizes in different upwind terrains are considered. Comprehensive interference characteristics are investigated by artificial neural networks and correlation analysis. Mechanism of the wakes vortex-induced resonance is discussed, too. Measured results show significant correlations exist in the distributions of the interference factors of different configurations and upwind terrains and, therefore, a series of relevant regression equations are proposed to simplify the complexity of the multi-parameter wind induced interference effects between two tall buildings.

Delayed Parallel Interference Cancellation for GPS C/A Code Receivers

  • Glennon, Eamonn P.;Bryant, Roderick C.;Dempster, Andrew G.
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.2
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    • pp.261-266
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    • 2006
  • A number of different techniques are available to mitigate the problem of cross correlations caused by the limited dynamic range of the 10-bit Gold codes in the GPS C/A code. These techniques include successive-interference cancellation (SIC) and parallel-interference cancellation (PIC), where the strong signals are subtracted at IF prior to attempting to detect the weak signals. In this paper, a variation of these techniques is proposed whereby the subtraction process is delayed until after the correlation process, although still employing a pure reconstructed C/A code signal to permit prediction of the cross correlation process. The paper provides details on the method as well as showing the results obtained when the method was implemented using a software GPS receiver. The benefits of this approach are also described, as is the application of the method to the cancellation of CW interference.

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ML Frame Synchronization for Gaussian Channel with Co-channel Interference (가우스 잡음과 CO-CHANNEL 간섭이 존재하는 채널에서의 최대추정 프레임 동기)

  • 문병현;우홍체;김신환;이채욱
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.5
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    • pp.643-649
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    • 1993
  • The problem of locating a periodically inserted frame synchronization pattern in random data for a binary pulse amplitude modulated (PAM) digital communication system over a additive white Gaussian noise(AWGN) channel with co-channel interference is considered. The performance degradation of frame synchronization for the correlation rule due to the presence of co-channel interference is shown. The maximum likelihood(ML) decision rule for the frame synchronization over an AWGN channel with co-channel interference is derived. For the entire range of SNR considered, the ML frame synchronization rule obtains about 1dB signal energy gain over the correlation rule. Specially, the ML rule obtains as much as 2dB gain over the correlation rule when the SNR is greater than 0dB.

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Adaptive Interference Cancellation Using CMA-Correlation Normalized LMS for WCDMA System

  • Han, Yong-Sik;Yang, Woon-Geun
    • Journal of information and communication convergence engineering
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    • v.8 no.2
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    • pp.155-158
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    • 2010
  • In this article, we proposed a new interference canceller using the adaptive algorithm. We designed constant modulus algorithm-correlation normailized least mean square (CMA-CNLMS) for wireless system. This structure is normalized LMS algorithm using correlation between the desired and input signal for cancelling the interference signals in the wideband code division multiple access (WCDMA) system. We showed that the proposed algorithm could improve the Mean Square Error (MSE) performance of LMS algorithm. MATLAB (Matrix Laboratory) is employed to analyze the proposed algorithm and to compare it with the experimental results. The MSE value of the LMS with mu=0.0001 was measured as - 12.5 dB, and that of the proposed algorithm was -19.5 dB which showed an improvement of 7dB.

The Correlation Study between Interference Test with the Weak Children(虛弱兒) Symptoms (주의력 간섭검사와 허약아 증상에 관한 연구 - 스트룹 아동 색상-단어검사 중심으로-)

  • Gok, Su-Yeong;Lyu, Sun-Ae;Lee, Seung-Yeon
    • The Journal of Pediatrics of Korean Medicine
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    • v.23 no.3
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    • pp.71-88
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    • 2009
  • Objectives The purpose of this study is to find out the correlation between Stroop interference and the symptoms of weak children. Methods Questionnaire and performed Stroop interference test were done by 145 patients in OO Oriental Medical Hospital from May to October 2009. 120 patients who were considered as the weak children were divided into two groups: Stroop Interference T score above average group and below average group, and were surveyed again. Results 1. The study showed that age, the highest marked subject and behavior habits correlate to interference score and subjects characteristics. 2. Weak children groups had the highest tendency of having weak heart followed by weak lung spleen, liver, and kidney. Normally, a patient belonged to more than one of the weak children groups. 3. The study showed that a group of children who has weak heart and lung were related to interference score. The group which earned below average interference score had the highest frequency of being children with weak heart group. The group scored above average, however, had the highest chance of being children with weak lung group. 4. The study showed that interference score was related to four out of fifty questions about the weak children symptoms. Plus, related questions were all about the heart weak children symptoms. Conclusions In conclusion, there were significant correlation between interference score and the group consists of children who were weak: more specifically with children with weak heart.

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A Chirp Rate Allocation Scheme for Multiple Access Interference Reduction in Chirp Spread Spectrum Systems (처프 확산 대역 시스템에서 다중 접속 간섭의 감소를 위한 처프율 할당 기법)

  • Kim, Kwang-Yul;Lee, Seung-Woo;Kim, Yong-Sin;Lee, Jae-Seang;Kim, Jin-Young;Shin, Yoan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.41 no.11
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    • pp.1420-1422
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    • 2016
  • In order to guarantee the multiuser transmission performance of a chirp spread spectrum system, the cross-correlation coefficient (CCC) among multiple users should be carefully considered. In this paper, we propose a chirp rate allocation scheme for reducing the multiple access interference based on the cross-correlation coefficient. The simulation results show that the proposed scheme can improve the multiple access interference performance.

Effect of Array Configurations on the Performance of GNSS Interference Suppression

  • Chang, Chung-Liang;Juang, Jyh-Ching
    • International Journal of Control, Automation, and Systems
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    • v.6 no.6
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    • pp.884-893
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    • 2008
  • This paper analyzes, through simulations, GNSS interference mitigation performance against wideband and narrowband interferences by using spatial-temporal adaptive processing(STAP). The mathematical analysis results demonstrate that the array configuration has a considerable effect on the spatial-temporal correlation function. Based on the results, different array configurations are presented to evaluate and observe the effect on interference mitigation. The analysis results are further assessed through simulations.

A Study on Optical Correlation for Indoor Positioning based LED-ID (LED-ID기반 실내 위치인식을 위한 Optical Correlation에 관한 연구)

  • Lee, Jung-Hoon;Cha, Jae-Sang
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.12 no.1
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    • pp.75-80
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    • 2013
  • In this paper, We proposed a Optical Correlation for indoor positioning based LED-ID. The proposed Optical Correlation has a advantage to low-interference between spread code number sequences and LED-ID. it is applied a spread code to reduce the interference with additional information based LED-ID. The additional information is enable to detect in transmitted signal using auto correlation. Also we designed and implemented the Optical Correlation for clearly detecting the additional information. Simulations were performed to confirm the performance of BER and the power of additional information. Optical Correlation simulator to indoor positioning based LED-ID was implemented to prove a usefulness.

Binary Nonlinear Joint Transform Correlator with Sinusoidal Iterative Filter in Spectrum Domain

  • Jeong, Man-Ho
    • Journal of the Optical Society of Korea
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    • v.14 no.4
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    • pp.357-362
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    • 2010
  • The joint transform correlator (JTC) has been the best known technique for pattern recognition and identification. This paper proposes a new technique of fringe adjustment by adopting a sinusoidal amplitude-modulated iterative filter convolved with an interference fringe pattern in the joint power spectrum (JPS) domain. The comparison of our new technique and other techniques is presented to show that the newly proposed technique can successfully improve both the correlation peaks and the peak signal-to-noise ratio (PSNR). Simulated results of enhanced interference fringes are also presented.

A Study of the Interference-Cancelled CDMA System Using Binary ZCD Spreading Codes (이진 ZCD확산코드를 이용한 저간섭 CDMA시스템에 관한 연구)

  • 차재상
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.18 no.4
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    • pp.149-154
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    • 2004
  • In this paper, Interference-Cancelled CDMA system using binary ZCD spreading codes is introduced. Proposed Interference-Cancelled CDMA system can be usefully used for the intra-cellular Interference-Cancelled wireless communication systems. Binary ZCD spreading code sets have various sequence period and family sizes and the ZCD properties of them are very effective for Interference-cancelled CDMA Systems. In this paper, we mathematically analyzed the system performance of our proposed Interference-Cancelled CDMA system in the AWGN channel and various interference environments such as MAI and MPI. Furthermore, using the BER performance simulation we certify the available interference cancellation properties of the proposed system.