• Title/Summary/Keyword: Noise Detection

Search Result 2,537, Processing Time 0.03 seconds

A Technique for the Quantitative Analysis of the Noise Jamming Effect (잡음재밍 효과에 대한 정량적 분석 기법)

  • Kim, Sung-Jin;Kang, Jong-Jin
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.8 no.4 s.23
    • /
    • pp.91-101
    • /
    • 2005
  • In this paper, a technique for the quantitative analysis of the noise jamming effect is proposed. This technique based upon the mathematical modeling for noise jammers and the probability theory for random processes analyses the jamming effect by means of the modeling of the relationship among jammer, radar variables and radar detection probability under noise jamming environment. Computer simulation results show that the proposed technique not only makes the quantitative analysis of the jamming effect possible, but also provides the basis for quantitative analysis of the electronic warfare environment.

On a Detection Scheme for Weak Deterministic Signals in Non-Additive Noise (비가산성 잡음에서의 약한 화정적 신호의 검파방식에 관하여)

  • Song, Iick-Ho
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.25 no.9
    • /
    • pp.1019-1026
    • /
    • 1988
  • A parametric detection scheme for determenistic signals is obtained in a generalized observation model which contains non-additive noise. The model employed in this paper includes several special cases such as those describing purely-additive noise, multiplicative noise, and signal dependent noise and allows the consideration of deterministic and random signals. Locally optimum detectors for known deterministic signals in the model are derived and analyzed for performance. It is shown that the locally optimum detectors are interesting generalizations of those for the purely-additive noise model. Performance of the locally optimum detectors designed for the generalized observation model is compared to that of other common detectors.

  • PDF

Performance analysis of FH/CPFSK system with the error-correcting code and the diversity under rayleigh fading channel with the thermal noise and the partial-band noise jamming (열잡음과 부분대역재밍이 존재하는 레일레이 페이딩 채널에서 오류정정부호와 다이버시티를 고려한 FH/CPFSK 시스템의 성능분석)

  • 곽진규;박진수
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.21 no.7
    • /
    • pp.1787-1802
    • /
    • 1996
  • In this paper, the performance for FH/CPFSK system with limiter-discriminator detection and integrage-and-dump post-detection filtering under thermal noie, partial-band noise jamming and rayleigh fading have been analyzed. The method of hard-decision diversity of which the transmitter repeated L times on different hops for each data symbol in a way to mutigate the effects of the jamming has been applied, and the receiver has been combined the L chips. Also, error-correcting code have been applied for improving performance of system. The thermal noise and partial-band noise jamming, intersymbol interference for all eight of the possible adjacent bit data patterns, and FM noise click for evaluating systems have been considered. Also optimum parameters to improve performance of FH/CPFSK system have been obtained and validities have been proved through computer simulation.

  • PDF

Improved Cancellation of Impulse Noise Using Rank-Order Method (Rank-Order 방법을 이용한 개선된 임펄스 잡음 제거)

  • Ko, Kyung-Woo;Lee, Cheol-Hee;Ha, Yeong-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.46 no.4
    • /
    • pp.9-15
    • /
    • 2009
  • This paper proposes a cancellation algorithm of impulse noise using a rank-order method. The proposed method is a fast and simple algorithm that is composed of two parts. The first part involves noise detection using a fuzzy technique, where an image is divided into RGB color channels. Then every pixel in each color channel is investigated and assigned a probability indicating its chances of being a noise pixel. At this time, the rank order method using a noise-detection mask is utilized for accurate noise detection. Thereafter, the second part involves noise-cancellation, where each noise-pixel value in an image is replaced in proportion to its fuzzy probability. Through the experiments, both the conventional and proposed methods were simulated and compared. As a result, it is shown that proposed method is able to detect noisy pixels more accurately, and produce resulting images with high PSNR values.

A Statistical Analysis of Edge Enhancing Filters and Their Effects on Edge Detection (에지개선 필터들의 통계적 분석과 에지검출에 대한 영향)

  • 박순영
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.18 no.11
    • /
    • pp.1635-1644
    • /
    • 1993
  • In this paper, we examine the statistical characteristics of edge enhancing filters and their efficacy as preprocessing operator before edge detection. In particular, edge enhancing filters called the Comparison and Selection(CS), Hachimura-kuwahara(HK), and Selective Average(SA) filters are considered. These filters can reduce noise while producing step-type edges, thus seem to be effective for preprocessing noisy images prior to applying edge detecors. The ability of edge enhancing filters to suppress white Gaussian noise and the error probabilities occured during the edge detection following SA prefiltering are evaluated statistically through numerical analysis. The effect of prefiltering on edge detection is assessed by applying the edge enhancing fitters to a noise image degraded by additive white noise prior to applying the Sobel operator and the Laplacian of Gaussian( LoG ) operator, respectively. It is shown that the edge enhancing filters tend to produce ideal step-type edges while reducing the noise reasonably well, and the use of edge enhancing filters prior to edge detection can improve the performance of subsequent edge detector.

  • PDF

Robust Entropy Based Voice Activity Detection Using Parameter Reconstruction in Noisy Environment

  • Han, Hag-Yong;Lee, Kwang-Seok;Koh, Si-Young;Hur, Kang-In
    • Journal of information and communication convergence engineering
    • /
    • v.1 no.4
    • /
    • pp.205-208
    • /
    • 2003
  • Voice activity detection is a important problem in the speech recognition and speech communication. This paper introduces new feature parameter which are reconstructed by spectral entropy of information theory for robust voice activity detection in the noise environment, then analyzes and compares it with energy method of voice activity detection and performance. In experiments, we confirmed that spectral entropy and its reconstructed parameter are superior than the energy method for robust voice activity detection in the various noise environment.

Reliable Measurement Selection for The Small Target Detection and Tracking in The IR Scanning Images (적외선 주사 영상에서 소형 표적의 탐지 및 추적을 위한 신뢰성 있는 측정치 선택 기법)

  • Yang, Yu-Kyung;Kim, Sung-Ho
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.11 no.1
    • /
    • pp.75-84
    • /
    • 2008
  • A new automatic small target detection and tracking algorithm for the real-time IR surveillance system is presented. The automatic target detection and tracking algorithm of the real-time systems, requires low complexity and robust tracking performance in the cluttered environment. Linear-array and parallel-scan IR systems usually suffer from severe scan noise caused by the detector non-uniformity. After the spatial filtering and thresholding, this scan noise still remains as high amplitude clutter which degrades the target detection rate and tracking performance. In this paper, we propose a new feature which consists of area and validity information of a measurement. By adopting this feature to the measurements selection and track confirmation, we can increase the target detection rate and reduce both the track loss rate and false track rate. From the experimental results, we can validate the feasibility of the proposed method in the noisy IR images.

An Edge Detection Algorithm using Modified Mask in AWGN Environment (AWGN 환경에서 변형된 마스크를 이용한 에지 검출 알고리즘)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2013.05a
    • /
    • pp.892-894
    • /
    • 2013
  • Edge has been utilized in various application fields with development of technique of digital image processing. In conventional edge detection methods, there are some methods using mask including Sobel, Prewitt, Roberts and Laplacian operator. Those methods are that implement is simple but generates errors of edge detection in images added AWGN(additive white Gaussian noise). Therefore, to compensate the defect of those methods, in this paper, an edge detection algorithm using modified mask is proposed, and it showed superior edge detection property in AWGN.

  • PDF

A Study on Edge Detection using Local Mask in AWGN Environments (AWGN 환경에서 국부 마스크를 이용한 에지 검출에 관한 연구)

  • Lee, Chang-Young;Hwang, Yeong-Yeun;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2014.05a
    • /
    • pp.801-803
    • /
    • 2014
  • In the modern society, image processing is utilized in various fields. Edge detection used for image processing as such is essential for most of the applications. Accordingly, there are studies conducted both in and out of Korea in order to detect edge. Representative edge detection methods include Sobel, Prewitt and Roberts. However, these methods are rather limited when it comes to the edge detection characteristics when used for the image with damaged AWGN(additive white Gaussian noise). Thus, this paper presented edge detection method utilizing local mask in order to overcome the shortcomings of the existing methods.

  • PDF

BM3D and Deep Image Prior based Denoising for the Defense against Adversarial Attacks on Malware Detection Networks

  • Sandra, Kumi;Lee, Suk-Ho
    • International journal of advanced smart convergence
    • /
    • v.10 no.3
    • /
    • pp.163-171
    • /
    • 2021
  • Recently, Machine Learning-based visualization approaches have been proposed to combat the problem of malware detection. Unfortunately, these techniques are exposed to Adversarial examples. Adversarial examples are noises which can deceive the deep learning based malware detection network such that the malware becomes unrecognizable. To address the shortcomings of these approaches, we present Block-matching and 3D filtering (BM3D) algorithm and deep image prior based denoising technique to defend against adversarial examples on visualization-based malware detection systems. The BM3D based denoising method eliminates most of the adversarial noise. After that the deep image prior based denoising removes the remaining subtle noise. Experimental results on the MS BIG malware dataset and benign samples show that the proposed denoising based defense recovers the performance of the adversarial attacked CNN model for malware detection to some extent.