Journal articles: 'Additive White Gaussian Noise (AWGN)'

1

Zhou, Yuqian, Jianbo Jiao, Haibin Huang, Jue Wang, and Thomas Huang. "Adaptation Strategies for Applying AWGN-Based Denoiser to Realistic Noise." Proceedings of the AAAI Conference on Artificial Intelligence 33 (July 17, 2019): 10085–86. http://dx.doi.org/10.1609/aaai.v33i01.330110085.

Full text

Abstract:

Discriminative learning based denoising model trained with Additive White Gaussian Noise (AWGN) performs well on synthesized noise. However, realistic noise can be spatialvariant, signal-dependent and a mixture of complicated noises. In this paper, we explore multiple strategies for applying an AWGN-based denoiser to realistic noise. Specifically, we trained a deep network integrating noise estimating and denoiser with mixed Gaussian (AWGN) and Random Value Impulse Noise (RVIN). To adapt the model to realistic noises, we investigated multi-channel, multi-scale and super-resolution approaches. Our preliminary results demonstrated the effectiveness of the newly-proposed noise model and adaptation strategies.

APA, Harvard, Vancouver, ISO, and other styles

2

Huang, Chengwei, Guoming Chen, Hua Yu, Yongqiang Bao, and Li Zhao. "Speech Emotion Recognition under White Noise." Archives of Acoustics 38, no. 4 (2013): 457–63. http://dx.doi.org/10.2478/aoa-2013-0054.

Full text

Abstract:

Abstract Speaker‘s emotional states are recognized from speech signal with Additive white Gaussian noise (AWGN). The influence of white noise on a typical emotion recogniztion system is studied. The emotion classifier is implemented with Gaussian mixture model (GMM). A Chinese speech emotion database is used for training and testing, which includes nine emotion classes (e.g. happiness, sadness, anger, surprise, fear, anxiety, hesitation, confidence and neutral state). Two speech enhancement algorithms are introduced for improved emotion classification. In the experiments, the Gaussian mixture model is trained on the clean speech data, while tested under AWGN with various signal to noise ratios (SNRs). The emotion class model and the dimension space model are both adopted for the evaluation of the emotion recognition system. Regarding the emotion class model, the nine emotion classes are classified. Considering the dimension space model, the arousal dimension and the valence dimension are classified into positive regions or negative regions. The experimental results show that the speech enhancement algorithms constantly improve the performance of our emotion recognition system under various SNRs, and the positive emotions are more likely to be miss-classified as negative emotions under white noise environment.

APA, Harvard, Vancouver, ISO, and other styles

3

Liu, Haoqiang, Hongbo Zhao, Xiaowen Chen, and Wenquan Feng. "An optimized initialization for LDPC decoding over GF(q) in impulsive noise environments." PLOS ONE 16, no. 5 (2021): e0250930. http://dx.doi.org/10.1371/journal.pone.0250930.

Full text

Abstract:

Modern navigation satellite communication has the characteristic of high transmitting rate. To avoid bit errors in data transmission, low density parity check (LDPC) codes are widely recognized as efficient ways for navigation communication. Conventionally, the LDPC decoding is applied for additive white Gaussian noise (AWGN) channel and degrades severely while facing the impulsive noise. However, navigation communication often suffers from impulsive interference due to the occurrence of high amplitude “spikes”. At this time, the conventional Gaussian noise assumption is inadequate. The impulsive component of interference has been found to be significant which influences the reliability of transmitted information. Therefore the LDPC decoding algorithms for AWGN channel are not suitable for impulsive noise environments. Consider that LDPC codes over GF(q) perform better than binary LDPC in resisting burst errors for current navigation system, it is necessary to conduct research on LDPC codes over GF(q). In this paper, an optimized initialization by calculating posterior probabilities of received symbols is proposed for non-binary LDPC decoding on additive white Class A noise (AWAN) channel. To verify the performance of the proposed initialization, extensive experiments are performed in terms of convergence, validity, and robustness. Preliminary results demonstrate that the decoding algorithm with the optimized initialization for non-binary LDPC codes performs better than the competing methods and that of binary LDPC codes on AWAN channel.

APA, Harvard, Vancouver, ISO, and other styles

4

Kittisuwan, Pichid. "Medical image denoising using simple form of MMSE estimation in Poisson–Gaussian noise model." International Journal of Biomathematics 09, no. 02 (2016): 1650020. http://dx.doi.org/10.1142/s1793524516500200.

Full text

Abstract:

Poisson–Gaussian noise is the basis of image formation for a great number of imaging systems used in variety of applications, including medical and astronomical imaging. In wavelet domain, the application of Bayesian estimation method with generalized Anscombe transform in Poisson–Gaussian noise reduction algorithm has shown remarkable success over the last decade. The generalized Anscombe transform is exerted to convert the Poisson–Gaussian noise into an additive white Gaussian noise (AWGN). So, the resulting data can be denoised with any algorithm designed for the removal of AWGN. Here, we present simple form of minimum mean square error (MMSE) estimator for logistic distribution in Poisson–Gaussian noise. The experimental results show that the proposed method yields good denoising results.

APA, Harvard, Vancouver, ISO, and other styles

5

Arora, Sahil, and Nirvair Neeru. "Speech Identification using GFCC, Additive White Gaussian Noise (AWGN) and Wavelet Filter." International Journal of Computer Applications 146, no. 9 (2016): 17–24. http://dx.doi.org/10.5120/ijca2016910854.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Zhou, Yuqian, Jianbo Jiao, Haibin Huang, et al. "When AWGN-Based Denoiser Meets Real Noises." Proceedings of the AAAI Conference on Artificial Intelligence 34, no. 07 (2020): 13074–81. http://dx.doi.org/10.1609/aaai.v34i07.7009.

Full text

Abstract:

Discriminative learning based image denoisers have achieved promising performance on synthetic noises such as Additive White Gaussian Noise (AWGN). The synthetic noises adopted in most previous work are pixel-independent, but real noises are mostly spatially/channel-correlated and spatially/channel-variant. This domain gap yields unsatisfied performance on images with real noises if the model is only trained with AWGN. In this paper, we propose a novel approach to boost the performance of a real image denoiser which is trained only with synthetic pixel-independent noise data dominated by AWGN. First, we train a deep model that consists of a noise estimator and a denoiser with mixed AWGN and Random Value Impulse Noise (RVIN). We then investigate Pixel-shuffle Down-sampling (PD) strategy to adapt the trained model to real noises. Extensive experiments demonstrate the effectiveness and generalization of the proposed approach. Notably, our method achieves state-of-the-art performance on real sRGB images in the DND benchmark among models trained with synthetic noises. Codes are available at https://github.com/yzhouas/PD-Denoising-pytorch.

APA, Harvard, Vancouver, ISO, and other styles

7

Thakur, Mohit, and Gerhard Kramer. "Quasi-Concavity for Gaussian Multicast Relay Channels." Entropy 21, no. 2 (2019): 109. http://dx.doi.org/10.3390/e21020109.

Full text

Abstract:

Standard upper and lower bounds on the capacity of relay channels are cut-set (CS), decode-forward (DF), and quantize-forward (QF) rates. For real additive white Gaussian noise (AWGN) multicast relay channels with one source node and one relay node, these bounds are shown to be quasi-concave in the receiver signal-to-noise ratios and the squared source-relay correlation coefficient. Furthermore, the CS rates are shown to be quasi-concave in the relay position for a fixed correlation coefficient, and the DF rates are shown to be quasi-concave in the relay position. The latter property characterizes the optimal relay position when using DF. The results extend to complex AWGN channels with random phase variations.

APA, Harvard, Vancouver, ISO, and other styles

8

Li, Chang, Yu Liu, Juan Cheng, et al. "Hyperspectral Unmixing with Bandwise Generalized Bilinear Model." Remote Sensing 10, no. 10 (2018): 1600. http://dx.doi.org/10.3390/rs10101600.

Full text

Abstract:

Generalized bilinear model (GBM) has received extensive attention in the field of hyperspectral nonlinear unmixing. Traditional GBM unmixing methods are usually assumed to be degraded only by additive white Gaussian noise (AWGN), and the intensity of AWGN in each band of hyperspectral image (HSI) is assumed to be the same. However, the real HSIs are usually degraded by mixture of various kinds of noise, which include Gaussian noise, impulse noise, dead pixels or lines, stripes, and so on. Besides, the intensity of AWGN is usually different for each band of HSI. To address the above mentioned issues, we propose a novel nonlinear unmixing method based on the bandwise generalized bilinear model (NU-BGBM), which can be adapted to the presence of complex mixed noise in real HSI. Besides, the alternative direction method of multipliers (ADMM) is adopted to solve the proposed NU-BGBM. Finally, extensive experiments are conducted to demonstrate the effectiveness of the proposed NU-BGBM compared with some other state-of-the-art unmixing methods.

APA, Harvard, Vancouver, ISO, and other styles

9

Ni'amah, Khoirun, Muhammad Panji Kusuma Praja, and Yuninda Dwianti Marimbun. "Comparative Analysis of 16-QAM and 64-QAM Modulation in Additive White Gaussian Noise and Rayleigh Fading Channels." CESS (Journal of Computer Engineering, System and Science) 7, no. 1 (2021): 90. http://dx.doi.org/10.24114/cess.v7i1.26729.

Full text

Abstract:

This reseach simulates and analyzes paramaters bit error rate (BER) of 16-QAM and 64-QAM modulation on Additive White Gaussian Noise and Rayleigh Fading channels. This research aims to determine 5G modulation with the level of data quality after the transmission process is carried out. The modulation simulation results obtained will be compared with the theoretical bit error rate (BER). The simulation results obtained from the two channel scenarios used are 16-QAM modulation reaching BER 10-4, AWGN channel only requires 15 dB Eb/N0 and for Rayleigh Fading channel it requires 38 dB Eb/N0. The BER theoretical results obtained for the 16-QAM modulation of the AWGN channel have a difference of 3 dB with the simulation results, while for the Rayleigh Fading channel it is 5 dB. Then, the simulation results of 64-QAM modulation AWGN channel to achieve BER 10-4 requires Eb/N0 of 24.6 dB, Rayleigh Fading of 47 dB. The theoretical results of BER obtained for the 64-QAM modulation of the AWGN channel have a difference of 1 dB with the simulation results, while for the Rayleigh Fading channel it is 0.5 dB. In this study, between 16-QAM and 64-QAM 5G modulation is more suitable to use 16-QAM modulation because it requires less power to achieve the desired BER 10-4.

APA, Harvard, Vancouver, ISO, and other styles

10

Kittisuwan, Pichid. "Image enhancement via MMSE estimation of Gaussian scale mixture with Maxwell density in AWGN." Journal of Innovative Optical Health Sciences 09, no. 02 (2016): 1650021. http://dx.doi.org/10.1142/s1793545816500218.

Full text

Abstract:

In optical techniques, noise signal is a classical problem in medical image processing. Recently, there has been considerable interest in using the wavelet transform with Bayesian estimation as a powerful tool for recovering image from noisy data. In wavelet domain, if Bayesian estimator is used for denoising problem, the solution requires a prior knowledge about the distribution of wavelet coefficients. Indeed, wavelet coefficients might be better modeled by super Gaussian density. The super Gaussian density can be generated by Gaussian scale mixture (GSM). So, we present new minimum mean square error (MMSE) estimator for spherically-contoured GSM with Maxwell distribution in additive white Gaussian noise (AWGN). We compare our proposed method to current state-of-the-art method applied on standard test image and we quantify achieved performance improvement.

APA, Harvard, Vancouver, ISO, and other styles

11

Rojas, Alejandro J. "Stabilizability of nonminimum phase unstable plants with arbitrary multiplicity over AWGN channels." Sba: Controle & Automação Sociedade Brasileira de Automatica 23, no. 4 (2012): 404–14. http://dx.doi.org/10.1590/s0103-17592012000400002.

Full text

Abstract:

In the present paper we obtain the infimal signal-to-noise ratio (SNR) required for the stabilizability of a linear output feedback loop over an additive white Gaussian noise (AWGN) channel in closed-form. The focus on AWGN channels allow us to then define the minimal channel capacity required for stabilizability. Finally, the infimal SNR for stabilizability also allow us to identify in closed-form the related stabilizing Hermitian positive semidefinite solution to the continuous-time algebraic Riccati equation of LQ control with vanishing state weight and repeated eigenvalues.

APA, Harvard, Vancouver, ISO, and other styles

12

Chen, Chao-Yang, Weihua Gui, Zhi-Hong Guan, Shaowu Zhou, and Cailun Huang. "Optimal Tracking Performance of MIMO Discrete-Time Systems with Network Parameters." Discrete Dynamics in Nature and Society 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/6826130.

Full text

Abstract:

The optimal regulation properties of multi-input and multioutput (MIMO) discrete-time networked control systems (NCSs), over additive white Gaussian noise (AWGN) fading channels, based on state space representation, are investigated. The average performance index is introduced. Moreover, the regulation performance is measured by the control energy and the error energy of the system, and fundamental limitations are obtained. Two kinds of network parameters, fading and the additive white Gaussian noise, are considered. The best attainable regulation performance limitations can be obtained by the limiting steady state solution of the corresponding algebraic Riccati equation (ARE). The simulation results are given to demonstrate the main results of the theoretical development.

APA, Harvard, Vancouver, ISO, and other styles

13

Al Bassam, Nizar, and Oday Jerew. "Design and Implementation of a Chaotic Scheme in Additive White Gaussian Noise Channel." Journal of Computer Networks and Communications 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/5976282.

Full text

Abstract:

A new chaotic scheme named Flipped Chaotic On-Off Keying (FCOOK) is proposed for binary transmission. In FCOOK, the low correlation value between the stationary signal and its mirrored version is utilized. Transmitted signal for binary 1 is a chaotic segment added to its time flipped (mirrored) version within one bit duration, while in binary 0, no transmission takes place within the same bit duration. The proposed scheme is compared with the standard chaotic systems: Differential Chaos Shift Keying (DCSK) and Correlation Delay Shift Keying (CDSK). The Bit Error Rate (BER) of FCOOK is studied analytically based on Gaussian approximation method. Results show that the BER performance of FCOOK outperforms DCSK and CDSK in AWGN channel environment and with variousEb/Nolevels. Additionally, FCOOK offers a double bit rate compared with the standard DCSK.

APA, Harvard, Vancouver, ISO, and other styles

14

Enayet Ullah, Shaikh, Md Golam Rashed, and Most Farjana Sharmin. "Encrypted message transmission in a QO-STBC encoded MISO wireless Communication system under implementation of low complexity ML decoding algorithm." INTERNATIONAL JOURNAL OF COMPUTERS & TECHNOLOGY 2, no. 2 (2012): 53–58. http://dx.doi.org/10.24297/ijct.v2i1.2617.

Full text

Abstract:

In this paper, we made a comprehensive BER simulation study of a quasi- orthogonal space time block encoded (QO-STBC) multiple-input single output(MISO) system. The communication system under investigation has incorporated four digital modulations (QPSK, QAM, 16PSK and 16QAM) over an Additative White Gaussian Noise (AWGN) and Raleigh fading channels for three transmit and one receive antennas. In its FEC channel coding section, three schemes such as Cyclic, Reed-Solomon and Â½-rated convolutionally encoding have been used. Under implementation of merely low complexity ML decoding based channel estimation and RSA cryptographic encoding /decoding algorithms, it is observable from conducted simulation test on encrypted text message transmission that the communication system with QAM digital modulation and Â½-rated convolutionally encoding techniques is highly effective to combat inherent interferences under Raleigh fading and additive white Gaussian noise (AWGN) channels. It is also noticeable from the study that the retrieving performance of the communication system degrades with the lowering of the signal to noise ratio (SNR) and increasing in order of modulation.

APA, Harvard, Vancouver, ISO, and other styles

15

Wang, Yifei, Huili Fan, Xuebo Zhang, et al. "A Viterbi Decoder under Class A Modeled Noise in Shallow Water." Wireless Communications and Mobile Computing 2022 (June 23, 2022): 1–10. http://dx.doi.org/10.1155/2022/1956938.

Full text

Abstract:

A traditional Viterbi decoder is primarily optimized for additive white Gaussian noise (AWGN). With the AWGN channel, it offers good decoding performance. However, the underwater acoustic communication (UAC) channel is extremely complicated. In addition to white noise, there are a variety of artificial and natural impulse noise that occur suddenly. The traditional Viterbi decoder cannot obtain the optimum performance under this case. In order to solve this problem, this paper introduces a novel Viterbi decoder with the impulsive noise, which is considered to be subjected to Middleton Class A distribution in shallow ocean. Since Middleton Class A noise is very complicated, a simplified model is first introduced. Then, the error analysis of simplified model under various parameters is discussed in detail. The analysis shows that the simplified one just leads to slight error. Hereafter, a novel Veterbi decoder using the simplified model is discussed. Compared to a traditional decoder, a preprocessing is just required. The performance of soft decision-based decoder in the Middleton Class A noise channel (MAIN) and AWGN are further compared. Based on our simulations, the new decoder can significantly improve the performance in comparison with conventional one, which further validates our presented method.

APA, Harvard, Vancouver, ISO, and other styles

16

Yuan, Quan, Zhenyun Peng, Zhencheng Chen, Yanke Guo, Bin Yang, and Xiangyan Zeng. "Medical Image Denoising Algorithm Based on Sparse Nonlocal Regularized Weighted Coding and Low Rank Constraint." Scientific Programming 2021 (June 7, 2021): 1–6. http://dx.doi.org/10.1155/2021/7008406.

Full text

Abstract:

Medical image information may be polluted by noise in the process of generation and transmission, which will seriously hinder the follow-up image processing and medical diagnosis. In medical images, there is a typical mixed noise composed of additive white Gaussian noise (AWGN) and impulse noise. In the conventional denoising methods, impulse noise is first removed, followed by the elimination of white Gaussian noise (WGN). However, it is difficult to separate the two kinds of noises completely in practical application. The existing denoising algorithm of weight coding based on sparse nonlocal regularization, which can simultaneously remove AWGN and impulse noise, is plagued by the problems of incomplete noise removal and serious loss of details. The denoising algorithm based on sparse representation and low rank constraint can preserve image details better. Thus, a medical image denoising algorithm based on sparse nonlocal regularization weighted coding and low rank constraint is proposed. The denoising effect of the proposed method and the original algorithm on computed tomography (CT) image and magnetic resonance (MR) image are compared. It is revealed that, under different σ and ρ values, the PSNR and FSIM values of CT and MRI images are evidently superior to those of traditional algorithms, suggesting that the algorithm proposed in this work has better denoising effects on medical images than traditional denoising algorithms.

APA, Harvard, Vancouver, ISO, and other styles

17

Li, Yongsong, Zhengzhou Li, Kai Wei, Weiqi Xiong, Jiangpeng Yu, and Bo Qi. "Noise Estimation for Image Sensor Based on Local Entropy and Median Absolute Deviation." Sensors 19, no. 2 (2019): 339. http://dx.doi.org/10.3390/s19020339.

Full text

Abstract:

Noise estimation for image sensor is a key technique in many image pre-processing applications such as blind de-noising. The existing noise estimation methods for additive white Gaussian noise (AWGN) and Poisson-Gaussian noise (PGN) may underestimate or overestimate the noise level in the situation of a heavy textured scene image. To cope with this problem, a novel homogenous block-based noise estimation method is proposed to calculate these noises in this paper. Initially, the noisy image is transformed into the map of local gray statistic entropy (LGSE), and the weakly textured image blocks can be selected with several biggest LGSE values in a descending order. Then, the Haar wavelet-based local median absolute deviation (HLMAD) is presented to compute the local variance of these selected homogenous blocks. After that, the noise parameters can be estimated accurately by applying the maximum likelihood estimation (MLE) to analyze the local mean and variance of selected blocks. Extensive experiments on synthesized noised images are induced and the experimental results show that the proposed method could not only more accurately estimate the noise of various scene images with different noise levels than the compared state-of-the-art methods, but also promote the performance of the blind de-noising algorithm.

APA, Harvard, Vancouver, ISO, and other styles

18

Zhang, Hong, and Wei Ping Ma. "Research on Overlapped Time Division Multiplexing in the Amplify-and-Forward Cooperative Mode." Applied Mechanics and Materials 713-715 (January 2015): 1103–6. http://dx.doi.org/10.4028/www.scientific.net/amm.713-715.1103.

Full text

Abstract:

In order to improve spectrum efficiency of cooperative communication system, Overlapped Time Division Multiplexing (OVTDM) is applied to Amplify-and-Forward (AF) cooperative communication system. The simulation results under Additive White Gaussian Noise (AWGN) channel show that the performance of new system is superior to that of corresponding AF cooperative communication system.

APA, Harvard, Vancouver, ISO, and other styles

19

Wu, Yan Jun, Xue Lu Yao, and Jiang Xia. "Analysis on Ranging and Velocity Measurement Performance of DS/FH Hybrid Spread Spectrum Signal." Advanced Materials Research 989-994 (July 2014): 4050–53. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.4050.

Full text

Abstract:

The measurement performance with the interference is presented with the new DS/FH hybrid spread spectrum signal system. The DS/FH system model is established. The change of the SNR ratio is obtained by analyzing the characteristics of three kinds of interference signal such as partial-band noise jamming (PBNJ), wide-band noise jamming (WBNJ) and additive white Gaussian noise (AWGN). Then the ranging and velocity measurement performance is got through the simulation.

APA, Harvard, Vancouver, ISO, and other styles

20

Liu, Qiang. "Rate-compatible LDPC convolutional codes over non-gaussian noise channel." MATEC Web of Conferences 309 (2020): 01010. http://dx.doi.org/10.1051/matecconf/202030901010.

Full text

Abstract:

This paper is aimed to study the characteristics of the underwater acoustic channel with non-Gaussian noise channel. And Gaussian mixture model (GMM) is utilized to fit the background noise over the non-Gaussian noise channel. Furthermore, coding techniques which use a sequence of rate-compatible low-density parity-check (RC-LDPC) convolutional codes with separate rates are constructed based on graph extension method. The performance study of RC-LDPC convolutional codes over non-Gaussian noise channel and the additive white Gaussian noise (AWGN) channel is performed. Study implementation of simulation is that modulation with binary phase shift keying (BPSK), and iterative decoding based on pipeline log-likelihood rate belief propagation (LLRBP) algorithm. Finally, it is shown that RC-LDPC convolutional codes have good bit-rate-error (BER) performance and can effectively reduce the impact of noise.

APA, Harvard, Vancouver, ISO, and other styles

21

Salih, Musab Elkheir, Xu Ming Zhang, and Ming Yue Ding. "An Improvement of Non-Local Means Denoising Method in the Presence of Large Noise." Applied Mechanics and Materials 263-266 (December 2012): 223–26. http://dx.doi.org/10.4028/www.scientific.net/amm.263-266.223.

Full text

Abstract:

The performance of singular value decomposition (SVD) based nonlocal mean (NLM) denoising method degrades when the noise is high. This paper describes an approach of an improvement of NLM denoising when the noise is large. Instead of SVD, we combine the kernel principal component analysis (KPCA) with NLM. It is demonstrated in terms of peak signal to noise ratio (PSNR) in decibels (dB) that the NLM denoising method is improved using various test images corrupted by large additive white Gaussian noise (AWGN)

APA, Harvard, Vancouver, ISO, and other styles

22

Seybold, Tamara, Marion Knopp, Christian Keimel, and Walter Stechele. "Beyond Standard Noise Models: Evaluating Denoising Algorithms with Respect to Realistic Camera Noise." International Journal of Semantic Computing 08, no. 02 (2014): 145–67. http://dx.doi.org/10.1142/s1793351x14400029.

Full text

Abstract:

The development and tuning of denoising algorithms is usually based on readily processed test images that are artificially degraded with additive white Gaussian noise (AWGN). While AWGN allows us to easily generate test data in a repeatable manner, it does not reflect the noise characteristics in a real digital camera. Realistic camera noise is signal-dependent and spatially correlated due to the demosaicking step required to obtain full-color images. Hence, the noise characteristic is fundamentally different from AWGN. Using such unrealistic data to test, optimize and compare denoising algorithms may lead to incorrect parameter tuning or suboptimal choices in research on denoising algorithms. In this paper, we therefore propose an approach to evaluate denoising algorithms with respect to realistic camera noise: we describe a new camera noise model that includes the full processing chain of a single sensor camera. We determine the visual quality of noisy and denoised test sequences using a subjective test with 18 participants. We show that the noise characteristics have a significant effect on visual quality. Quality metrics, which are required to compare denoising results, are applied, and we first evaluate the performance of 12 full-reference metrics. As no-reference metrics are especially useful for parameter tuning, we additionally evaluate five no-reference metrics with our realistic test data. We conclude that a more realistic noise model should be used in future research to improve the quality estimation of digital images and videos and to improve the research on denoising algorithms.

APA, Harvard, Vancouver, ISO, and other styles

23

Kirmizitas, Hikmet, and Nurettin Besli. "Image and Texture Independent Deep Learning Noise Estimation Using Multiple Frames." Elektronika ir Elektrotechnika 28, no. 6 (2022): 42–47. http://dx.doi.org/10.5755/j02.eie.30586.

Full text

Abstract:

In this study, a novel multiple frame based image and texture independent Convolutional Neural Network (CNN) noise estimator is introduced. Noise estimation is a crucial step for denoising algorithms, especially for ones that are called “non-blind”. The estimator works for additive Gaussian noise for varying noise levels. The noise levels studied in this work have a standard deviation equal to 5 to 25 increasing 5 by 5. Since there is no database for noisy multiple images to train and validate the network, two frames of synthetic noisy images with a variety of noise levels are created by adding Additive White Gaussian Noise (AWGN) to each clean image. The proposed method is applied on the most popular gray level images besides the color image databases such as Kodak, McMaster, BSDS500 in order to compare the results with the other works. Image databases comprise indoor and outdoor scenes that have fine details and richer texture. The estimator has an accuracy rate of 99 % for the classification and favourable results for the regression. The proposed method outperforms traditional methods in most cases. And the regression output can be used with any non-blind denoising method.

APA, Harvard, Vancouver, ISO, and other styles

24

Ibrahim, A. H. "Accuracy of Bit Error Probability for W-CDMA System Using Code Tree." Engineering, Technology & Applied Science Research 8, no. 2 (2018): 2834–38. http://dx.doi.org/10.48084/etasr.1991.

Full text

Abstract:

W-CDMA is radio access utilized for 3G cell frameworks. A code tree allocation scheme is one of the most explored channelization techniques, used to improve system performance and capacity through adjustable data rates. This work investigates the accuracy of bit error probability for W-CDMA system using code tree orthogonal variable spreading factor (OVSF) codes, compared to pseudo-noise (PN) codes under various noise conditions, such as additive white Gaussian Noise (AWGN) and Random Noise (RN). Results are carried out theoretically and by computer simulation. The simulation includes the scenario of simple model representation for W-CDMA system. It was concluded that, the system has better performance using OVSF compared with PN code under different noisy channels.

APA, Harvard, Vancouver, ISO, and other styles

25

Kittisuwan, Pichid. "Textural Region Denoising: Application in Agriculture." International Journal of Image and Graphics 18, no. 04 (2018): 1850024. http://dx.doi.org/10.1142/s0219467818500249.

Full text

Abstract:

Geo-science and remote sensing technologies play enormous roles in agriculture nowadays, especially in analysis of data from aerial images such as satellite images and drone images. Most agricultural images contain more textural regions than non-textural regions. Therefore, data management in terms of textural regions is very important. Indeed, additive white Gaussian noise (AWGN) is the fundamental problem in digital image analysis. In wavelet transform, Bayesian estimation is useful in several noise reduction methods. The Bayesian technique requires a prior modeling of noise-free wavelet coefficients. In non-textural regions, the wavelet coefficients might be better modeled by super-Gaussian density such as Laplacian, Pearson type VII, Cauchy, and two-sided gamma distributions. However, the statistical model of textural regions is Gaussian model. Therefore, in agricultural images, we require flexible model between super-Gaussian and Gaussian models. In fact, the generalized Gaussian distribution (GGD) is the suitable model for this problem. Therefore, we present new maximum a posteriori (MAP) estimator for spacial case of GGD in AWGN. Here, we obtained the analytical form solution. Moreover, this research work will also describe limitations of GGD application in Bayesian estimator. The simulation results illustrate that our presented method outperforms the state-of-the-art methods qualitatively and quantitatively.

APA, Harvard, Vancouver, ISO, and other styles

26

Ahmed, Anas. "Efficient Filter for EEG Signal Using Non Local Mean Approach." Journal of Al-Rafidain University College For Sciences ( Print ISSN: 1681-6870 ,Online ISSN: 2790-2293 ), no. 3 (October 8, 2021): 304–19. http://dx.doi.org/10.55562/jrucs.v41i3.189.

Full text

Abstract:

Non Local Mean (NLM) filter has attracted great attention within the images and signal processing field especially in the last ten years. The main contribution of this paper to the field of biomedical signals processing is introducing the straightforward application of the fast NLM filter to EEG signal contaminated with "Additive White Gaussian Noise" (AWGN). The performance of this filter is analysed by evaluating its optimal parameters. All the tests are conducted using actual EEG signal captured from human brain. The performance of this filter is determined using "Output Signal to Noise Ratio" (SNRo) and "Cross Correlation" (CC) criteria. The NLM filter exhibits excellent performance in rejection the AWGN from the EEG signal.

APA, Harvard, Vancouver, ISO, and other styles

27

Kittisuwan, P. "Textural Image Denoising Using Gumbel Random Vectors in Gaussian Noise." International Journal of Image and Graphics 17, no. 01 (2017): 1750003. http://dx.doi.org/10.1142/s0219467817500036.

Full text

Abstract:

Gaussian noise is an important problem in computer vision. The novel methods that become popular in recent years for Gaussian noise reduction are Bayesian techniques in wavelet domain. In wavelet domain, the Bayesian techniques require a prior distribution of wavelet coefficients. In general case, the wavelet coefficients might be better modeled by non-Gaussian density such as Laplacian, two-sided gamma, and Pearson type VII densities. However, statistical analysis of textural image is Gaussian model. So, we require flexible model between non-Gaussian and Gaussian models. Indeed, Gumbel density is a suitable model. So, we present new Bayesian estimator for Gumbel random vectors in AWGN (additive white Gaussian noise). The proposed method is applied to dual-tree complex wavelet transform (DT-CWT) as well as orthogonal discrete wavelet transform (DWT). The simulation results show that our proposed methods outperform the state-of-the-art methods qualitatively and quantitatively.

APA, Harvard, Vancouver, ISO, and other styles

28

Molchanov, Pavel, and Alexandr Totsky. "Application of Triple Correlation and Bispectrum for Interference Immunity Improvement in Telecommunications Systems." International Journal of Applied Mathematics and Computer Science 18, no. 3 (2008): 361–67. http://dx.doi.org/10.2478/v10006-008-0032-9.

Full text

Abstract:

Application of Triple Correlation and Bispectrum for Interference Immunity Improvement in Telecommunications SystemsThis paper presents a new noise immunity encoding/decoding technique by using the features of triple correlation and bispectrum widely employed in digital signal processing systems operating in noise environments. The triple correlation-and bispectrum-based encoding/decoding algorithm is tested for a digital radio telecommunications binary frequency shift keying system. The errorless decoding probability was analyzed by means of computer simulation for the transmission and reception of a test message in a radio channel disturbed by both additive white Gaussian noise (AWGN) and a mixture of an AWGN and an impulsive noise. Computer simulation results obtained for varying and less than unity signal-to-noise ratios at the demodulator input demonstrate a considerable improvement in the noise immunity of the technique suggested in comparison with the traditional redundant linear block encoding/decoding technique.

APA, Harvard, Vancouver, ISO, and other styles

29

Kittisuwan, P., and C. Chinrungrueng. "Differential Form of Bivariate MMSE Estimator Based on Gaussian Noise." Journal of Circuits, Systems and Computers 26, no. 01 (2016): 1750008. http://dx.doi.org/10.1142/s0218126617500086.

Full text

Abstract:

In fact, the noise signal is an important problem in signal, circuits and systems. The minimum mean square error (MMSE) estimation technique is useful in several additive white Gaussian noise (AWGN) reduction methods. Original form of MMSE estimator is the integral form. Unfortunately, integral form of MMSE estimator cannot be obtained in simple form for any interesting peaked, heavy-tailed densities (also known as super-Gaussian densities). In this work, we proposed a differential form of bivariate MMSE estimator. The development depends on bivariate Taylor series. The proposed estimator requires no integration. In fact, the derivation is an extension of the existing results for differential form of univariate MMSE estimator.

APA, Harvard, Vancouver, ISO, and other styles

30

Farooq, Muhammad Umar, Alexandre Graell i Amat, and Michael Lentmaier. "Threshold Computation for Spatially Coupled Turbo-Like Codes on the AWGN Channel." Entropy 23, no. 2 (2021): 240. http://dx.doi.org/10.3390/e23020240.

Full text

Abstract:

In this paper, we perform a belief propagation (BP) decoding threshold analysis of spatially coupled (SC) turbo-like codes (TCs) (SC-TCs) on the additive white Gaussian noise (AWGN) channel. We review Monte-Carlo density evolution (MC-DE) and efficient prediction methods, which determine the BP thresholds of SC-TCs over the AWGN channel. We demonstrate that instead of performing time-consuming MC-DE computations, the BP threshold of SC-TCs over the AWGN channel can be predicted very efficiently from their binary erasure channel (BEC) thresholds. From threshold results, we conjecture that the similarity of MC-DE and predicted thresholds is related to the threshold saturation capability as well as capacity-approaching maximum a posteriori (MAP) performance of an SC-TC ensemble.

APA, Harvard, Vancouver, ISO, and other styles

31

Chen, Zhenxing, Jiaheng Liu, Shuang Li, and Seog Geun Kang. "New 3D 16-Ary Signal Constellations and Their Symbol Error Probabilities in AWGN and Rayleigh Fading Channels." Wireless Communications and Mobile Computing 2018 (August 13, 2018): 1–6. http://dx.doi.org/10.1155/2018/7178631.

Full text

Abstract:

Two three-dimensional (3D) 16-ary signal constellations having extended lattice structures are presented in this paper. The theoretical symbol error probabilities (SEPs) of the new constellations in additive white Gaussian noise (AWGN) and Rayleigh fading channel are derived. Computer simulation confirms that the closed-form expressions for average SEPs of the constellations in the AWGN channel are very accurate. The theoretical SEP upper bounds in the Rayleigh fading channel are very tight. Since the presented constellations have larger minimum Euclidean distance (MED) than the conventional one, error performance can be improved up to 0.9 dB in an AWGN environment. Hence, the proposed constellations and their theoretical analysis can be used as a reference for the development of a wireless communication system with 3D signal constellations.

APA, Harvard, Vancouver, ISO, and other styles

32

El Ouargui, Ismail, Said Safi, and Miloud Frikel. "Minimum Array Elements for Resolution of Several Direction of Arrival Estimation Methods in Various Noise-Level Environments." Journal of Telecommunications and Information Technology 2 (June 29, 2018): 87–94. http://dx.doi.org/10.26636/jtit.2018.119417.

Full text

Abstract:

The resolution of a Direction of Arrival (DOA) estimation algorithm is determined based on its capability to resolve two closely spaced signals. In this paper, authors present and discuss the minimum number of array elements needed for the resolution of nearby sources in several DOA estimation methods. In the real world, the informative signals are corrupted by Additive White Gaussian Noise (AWGN). Thus, a higher signal-to-noise ratio (SNR) oﬀers a better resolution. Therefore, we show the performance of each method by applying the algorithms in diﬀerent noise level environments.

APA, Harvard, Vancouver, ISO, and other styles

33

Kittisuwan, Pichid. "Speckle Noise Reduction of Medical Imaging via Logistic Density in Redundant Wavelet Domain." International Journal on Artificial Intelligence Tools 27, no. 02 (2018): 1850006. http://dx.doi.org/10.1142/s0218213018500069.

Full text

Abstract:

In the digital world, artificial intelligence tools and machine learning algorithms are widely applied in analysis of medical images for identifying diseases and make diagnoses; for example, to make recognition and classification. Speckle noises affect all medical imaging systems. Therefore, reduction in corrupting speckle noises is very important, since it deteriorates the quality of the medical images and makes tasks such as recognition and classification difficult. Most existing denoising algorithms have been developed for the additive white Gaussian noise (AWGN). However, AWGN is not a speckle noise. Therefore, this work presents a novel speckle noise removal algorithm within the framework of Bayesian estimation and wavelet analysis. This research focuses on noise reduction by the Bayesian with wavelet-based method because it provides good efficiency in noise reduction and spends short time in processing. The subband decomposition of a logarithmically transformed image is best described by a family of heavy-tailed densities such as Logistic distribution. Then, this research proposes the maximum a posteriori (MAP) estimator assuming Logistic random vectors for each parent-child wavelet co-efficient of noise-free log-transformed data and log-normal density for speckle noises. Moreover, a redundant wavelet transform, i.e., the cycle-spinning method, is applied in our proposed methods. In our experiments, our proposed methods give promising denoising results.

APA, Harvard, Vancouver, ISO, and other styles

34

Malleswari, Pinjala N., Ch Hima Bindu, and K. Satya Prasad. "An Improved Denoising of Electrocardiogram Signals Based on Wavelet Thresholding." Journal of Biomimetics, Biomaterials and Biomedical Engineering 51 (June 14, 2021): 117–29. http://dx.doi.org/10.4028/www.scientific.net/jbbbe.51.117.

Full text

Abstract:

Electrocardiogram (ECG) is the most important signal in the biomedical field for the diagnosis of Cardiac Arrhythmia (CA). ECG signal often interrupted with various noises due to non-stationary nature which leads to poor diagnosis. Denoising process helps the physicians for accurate decision making in treatment. In many papers various noise elimination techniques are tried to enhance the signal quality. In this paper a novel hybrid denoising technique using EMD-DWT for the removal of various noises such as Additive White Gaussian Noise (AWGN), Baseline Wander (BW) noise, Power Line Interference (PLI) noise at various concentrations are compared to the conventional methods in terms of Root Mean Square Error (RSME), Signal to Noise Ratio (SNR), Peak Signal to Noise Ratio (PSNR), Cross-Correlation (CC) and Percent Root Square Difference (PRD). The average values of RMSE, SNR, PSNR, CC and PRD are 0.0890, 9.8821, 14.4464, 0.9872 and 10.9036 for the EMD approach, respectively, and 0.0707, 10.7181, 16.2824, 0.9874 and 10.7245 for the proposed EMD-DWT approach, respectively, by removing AWGN noise. Similarly BW noise and PLI are removed from the ECG signal by calculating the same quality metrics. The proposed methodology has lower RMSE and PRD values, higher SNR, PSNR and CC values than the conventional methods.

APA, Harvard, Vancouver, ISO, and other styles

35

Chisab, Raad Farhood. "An active technique for power saving in WSN under additive white gaussian noise channel." International Journal of Electrical and Computer Engineering (IJECE) 9, no. 1 (2019): 386. http://dx.doi.org/10.11591/ijece.v9i1.pp386-396.

Full text

Abstract:

The work with feature of self-power supply by solar cell or by the battery or together at the same time. Therefore, the power dissipation is the big problem in wireless sensor network (WSN) especially when it is works for long time. The efficient method for reducing the power consumption within working is needed. The process of reducing waste power is one of the top priorities of scientists and designers of wireless sensor networks. The aim of this paper is to find the dominant method to reduce the power consumption in the wireless sensor network in order to stay works for long time and maintain the links with other nodes without loss of connection and transfer the information correctly. In this paper, a modified method was invented to minimize power utilization per data bit in a connection. This new method depends on the optimization process for reducing the power consumption as low as possible. All the tests of simulation process were done in additive white Gaussian noise (AWGN) channel. Numerical results demonstrated that the new method reduce the power when different values of noise are present with different types of modulation. Also the distance that the WSN will reach the information to it will be increase with presence of various noise amounts with different types of modulation. As a result, the power was decreased and the signal was reach more distance.

APA, Harvard, Vancouver, ISO, and other styles

36

Nguyen, Tri Minh, Tu Thanh Nguyen, and Phuong Huu Nguyen. "Spectrum sensing in cognitive radio wireless networks for orthogonal freqnency division multiplexing in additive white Gaussian noise channel." Science and Technology Development Journal - Natural Sciences 1, T4 (2017): 180–86. http://dx.doi.org/10.32508/stdjns.v1it4.495.

Full text

Abstract:

Cognitive radio (CR) systems are one of the most interesting topics in recent years. They would enable more efficient use of the spectrum. The main problem of CR is how to dectect exactly the spectrum usage of primary users. There are many ways to do this, such as energy detector (ED), Axell’s detector, the sliding window detector, etc. Among them, cyclostationarity (CS) based dection methods attracted much attention because of their better results in low-SNR regimes. This paper will propose a method based on the autocorrelation property of orthogonal frequency division multiplexing (OFDM) signals in additive white Gaussian noise (AWGN).

APA, Harvard, Vancouver, ISO, and other styles

37

Liu, Mengmeng, Jianhua Zhang, and Ping Zhang. "Outage Probability of Dual-Hop Multiple Antenna Relay Systems with Interference at the Relay and Destination." International Journal of Antennas and Propagation 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/370684.

Full text

Abstract:

This paper analyzes the outage performance of a dual-hop relaying system in which the relay is equipped with multiple antennas, while the source and destination have a single antenna. New exact closed-form expressions for the outage probability of both the amplify-and-forward (AF) and the decode-and-forward (DF) relaying systems are derived, assuming that the relay and destination are impaired by cochannel interferers and additive white Gaussian noise (AWGN). Numerical results are presented to verify the theoretical analysis.

APA, Harvard, Vancouver, ISO, and other styles

38

Exel, Reinhard. "Receiver Design for Time-Based Ranging with IEEE 802.11b Signals." International Journal of Navigation and Observation 2012 (August 8, 2012): 1–15. http://dx.doi.org/10.1155/2012/743625.

Full text

Abstract:

This paper presents a ranging receiver architecture able to timestamp IEEE 802.11b Wireless LAN signals with sub-100 picosecond precision enabling time-based range measurements. Starting from the signal model, the performance of the proposed architecture is assessed in terms of statistical bounds when perturbed by zero-mean additive white Gaussian noise (AWGN) as well as in case of multipath propagation. Results of the proposed architecture, implemented in a Field Programmable Gate Array-(FPGA-) based prototype, are presented for different environments. For AWGN channels, the prototype system is able to attain an accuracy of 1.2 cm while the ranging accuracy degrades in dynamic multipath scenarios to about 0.6 m for 80% of the measurements due to the limited bandwidth of the signal.

APA, Harvard, Vancouver, ISO, and other styles

39

Ghareeb, Ibrahim, та Amani Atiani. "Bit Error Rate Analysis of Mobile Ad Hoc Networks over η − µ Fading Channels". مجلة جامعة فلسطين التقنية للأبحاث 2, № 2 (2021): 25–34. http://dx.doi.org/10.53671/pturj.v2i2.31.

Full text

Abstract:

In this paper the performance analysis of Mobile ad hoc networks (MANETs) is conducted for a differential QPSK (DQPSK) signals with post-detection equal gain combining (EGC) receiver operating over additive white Gaussian noise (AWGN) as well as for slow frequency nonselective η − µ fading channels, in which the diversity branches can have unequal signal-to-noise ratios (SNRs) as well as different severity parameters. The average bit error probability (ABEP) is evaluated using MGF-based approach. The average BER per multi-hop route of MANETs for this communication is studied.

APA, Harvard, Vancouver, ISO, and other styles

40

Ghareeb, Ibrahim, та Amani Atiani. "Bit Error Rate Analysis of Mobile Ad Hoc Networks over η − µ Fading Channels". مجلة جامعة فلسطين التقنية خضوري للأبحاث 2, № 2 (2021): 25–34. http://dx.doi.org/10.53671/ptukrj.v2i2.31.

Full text

Abstract:

In this paper the performance analysis of Mobile ad hoc networks (MANETs) is conducted for a differential QPSK (DQPSK) signals with post-detection equal gain combining (EGC) receiver operating over additive white Gaussian noise (AWGN) as well as for slow frequency nonselective η − µ fading channels, in which the diversity branches can have unequal signal-to-noise ratios (SNRs) as well as different severity parameters. The average bit error probability (ABEP) is evaluated using MGF-based approach. The average BER per multi-hop route of MANETs for this communication is studied.

APA, Harvard, Vancouver, ISO, and other styles

41

Kittisuwan, Pichid. "Image denoising via analytical form of adaptive generalized Gaussian random vectors in AWGN with MMSE estimator for local adaptive parameter." International Journal of Wavelets, Multiresolution and Information Processing 13, no. 04 (2015): 1550026. http://dx.doi.org/10.1142/s0219691315500265.

Full text

Abstract:

In this paper, we present new Bayesian estimators for adaptive generalized Gaussian (GG) random vectors in additive white Gaussian noise (AWGN). The derivations are an extension of existing results for Pearson type VII random vectors in AWGN. Pearson type VII random vectors is one of the distribution that successfully use for image denoising. However, Pearson type VII distribution have higher-order moment in statistical parameter for fitted the data such as mean, variance and kurtosis. In our literature, where high-order statistics were used, better performance can be obtained but with much higher computational complexity. In fact, adaptive GG random vectors is similar to Pearson type VII random vectors. However, the special case of adaptive GG random vectors has only first few statistical moments such as adaptive parameter. So, the proposed method can be calculated very fast, without any complex step. In fact, the adaptive parameter of adaptive GG density is the function of standard deviation. Here, we employ minimum mean square error (MMSE) estimation to calculate local observed variances with gamma density prior for local observed variances and Gaussian distribution for noisy wavelet coefficients. In our experiments, our proposed method gives promising denoising results with moderate complexity.

APA, Harvard, Vancouver, ISO, and other styles

42

Kittisuwan, Pichid. "Image denoising via Bayesian estimation of local variance with Maxwell density prior." Journal of Multiscale Modelling 06, no. 02 (2015): 1550002. http://dx.doi.org/10.1142/s175697371550002x.

Full text

Abstract:

The need for efficient image denoising methods has grown with the massive production of digital images and movies of all kinds. The distortion of images by additive white Gaussian noise (AWGN) is common during its processing and transmission. This paper is concerned with dual-tree complex wavelet-based image denoising using Bayesian techniques. Indeed, one of the cruxes of the Bayesian image denoising algorithms is to estimate the local variance of the image. Here, we employ maximum a posteriori (MAP) estimation to calculate local observed variance with Maxwell density prior for local observed variance and Gaussian distribution for noisy wavelet coefficients. Evidently, our selection of prior distribution is motivated by analytical and computational tractability. The experimental results show that the proposed method yields good denoising results.

APA, Harvard, Vancouver, ISO, and other styles

43

Abdulhamid, Mohanad F., and Onyango Ben Sewe. "Performance of UWB-WBAN System Over Awgn Channel." Technological Engineering 15, no. 1 (2018): 20–25. http://dx.doi.org/10.1515/teen-2018-0004.

Full text

Abstract:

Abstract The major constraints in the design of Wireless Body Area Network(WBAN) can be attributed to the battery autonomy, need for high data rate services and low interference from the devices operating within the industrial, scientific and medical (ISM) bands. To meet the demand for high data rate services and low power spectral density to avoid ISM band interference, an ultra-wide band(UWB) system based technology has been proposed. This paper focuses on the design and demonstration of an UWB modem to be used in the WBAN applications and the evaluation of its performance in a near-real world scenarios affected by additive white Gaussian noise(AWGN) interference. The modem is tested with different values of signal to noise ratio(SNR). Results show that the performance of the modem degrades as the value of SNR decreases.

APA, Harvard, Vancouver, ISO, and other styles

44

Zhao, Shuai, and Peiming Shi. "A Novel Piecewise Tri-Stable Stochastic Resonance System Driven by Dichotomous Noise." Sensors 23, no. 2 (2023): 1022. http://dx.doi.org/10.3390/s23021022.

Full text

Abstract:

Stochastic resonance (SR) has been widely studied as a means of signal processing since its conception. Since SR is different from other denoising methods in nature, it can be used for not only feature extraction but also signal enhancement. Additive white Gaussian noise (AWGN) is often used as a driving source in SR research due to its convenience in numerical simulation and uniform distribution, but as a special noise, it is of great significance to study the SR principle of dichotomous noise as a driving source for nonlinear dynamics. In this paper, the method of piecewise tri-stable SR (PTSR) driven by dichotomous noise is studied, and it is verified that signal enhancement can still be achieved in the PTSR system. At the same time, the influence of the parameters of the PTSR system, periodic signal, and dichotomous noise on the mean of signal-to-noise ratio gain (SNR-GM) is analyzed. Finally, dichotomous noise and AWGN are used as the driving sources of the PTSR system, and the signal enhancement ability and noise resistance ability of the two drivers are compared.

APA, Harvard, Vancouver, ISO, and other styles

45

Abdalla, Abdi T. "Determination of Cramer-Rao Lower Bound (CRLB) and Minimum Variance Unbiased Estimator of a DC Signal in AWGN Using Laplace Transform." Tanzania Journal of Science 47, no. 5 (2021): 1581–87. http://dx.doi.org/10.4314/tjs.v47i5.8.

Full text

Abstract:

This paper presents an alternative approach for the determination of Cramer-Rao Lower Bound (CRLB) and Minimum Variance Unbiased Estimator (MVUE) using Laplace transformation. In this work, a DC signal in Additive White Gaussian Noise (AWGN) was considered. During the investigation, a number of experiments were conducted to analyze different possible outputs under different conditions, and then the patterns of the outcomes were studied. Finally closed-form expressions for the CRLB and MVUE were deduced employing the Laplace transformation. The resulting expressions showed that the proposed method has almost the same number of steps as the existing method. However, the latter requires only the knowledge of algebra to arrive at the CRLB expressions contrary to the existing approach where a strong mathematical background is required and hence making it superior over the existing method, in that sense. Keywords: Additive White Gaussian Noise, Cramer-Rao Lower Bound, DC-Value, Laplace transform, and Minimum Variance Unbiased Estimator (MVUE).

APA, Harvard, Vancouver, ISO, and other styles

46

Zhang, Lei, Bin Hu, Jun Wu, and Zhong Hua Liu. "Complexity Constrained Detection of Continuous Phase Modulation Based on Breadth-First Method." Applied Mechanics and Materials 263-266 (December 2012): 331–34. http://dx.doi.org/10.4028/www.scientific.net/amm.263-266.331.

Full text

Abstract:

This paper solves the problem of high detection complexity of continuous phase modulation (CPM) signals over additive white Gaussian noise (AWGN) channel. A complexity constrained sequence detection method for CPM is provided using breadth-first maximum-likelihood sequence detection. The derived result is to reserve only those states which are closest to the received signal in the Euclidean distance after retain one best path for every state. Compared with the maximum-likelihood detector based on Viterbi Algorithm (VA), a significant reduction in complexity is obtained by the suggested detector while maintaining good performances.

APA, Harvard, Vancouver, ISO, and other styles

47

Ghauri, Sajjad Ahmed, Ijaz Mansoor Qureshi, Tanveer Ahmed Cheema, and Aqdas Naveed Malik. "A Novel Modulation Classification Approach Using Gabor Filter Network." Scientific World Journal 2014 (2014): 1–14. http://dx.doi.org/10.1155/2014/643671.

Full text

Abstract:

A Gabor filter network based approach is used for feature extraction and classification of digital modulated signals by adaptively tuning the parameters of Gabor filter network. Modulation classification of digitally modulated signals is done under the influence of additive white Gaussian noise (AWGN). The modulations considered for the classification purpose are PSK 2 to 64, FSK 2 to 64, and QAM 4 to 64. The Gabor filter network uses the network structure of two layers; the first layer which is input layer constitutes the adaptive feature extraction part and the second layer constitutes the signal classification part. The Gabor atom parameters are tuned using Delta rule and updating of weights of Gabor filter using least mean square (LMS) algorithm. The simulation results show that proposed novel modulation classification algorithm has high classification accuracy at low signal to noise ratio (SNR) on AWGN channel.

APA, Harvard, Vancouver, ISO, and other styles

48

Oyetola, Oluwadamilola Kehinde, Ayodeji Akinsoji Okubanjo, Alexander Akpofure Okandeji, Peter Olufemi Alao, Martins O. Osifeko, and Omowunmi Grace Olasunkanmi. "SYMBOL ERROR PROBABILITY OF 16-QAM SYSTEM OVER AWGN AND RAYLEIGH FADING CHANNELS." African Journal of Science and Nature 7 (November 6, 2020): 29. http://dx.doi.org/10.46881/ajsn.v7i0.154.

Full text

Abstract:

Wireless communication had transformed the mode of human interactions in recent times, distance is no longer a barrier as messages can be sent several miles apart within few seconds. In addition, the pervasive adoption of mobile communication system had engendered researchers to device new and effective technologies to enhance Quality of Service (QOS) offered by service providers. This is obvious in the deployment of trending mobile generations such as 2G, 3G and 4G systems for high speed voice and data services. Nevertheless, these systems are still embattled with unpredictable impairment such as noise in fading channels that impedes optimal system performance. In this paper, performance evaluation of 16–Quadrature Amplitude Modulation (16-QAM) system over Additive White Gaussian Noise (AWGN) and Rayleigh Channels using simulated and theoretical approach is presented. Theoretical mathematical expression for Symbol Error Rate(SEP) was derived, and simulation was setup using MATLAB/SIMULINK for performance evaluation. The results show that SEP is dependent on signal-noise-ratio (SNR) for both methods. However, SEP wasvery high for Rayleigh channel as compared with AWGN.

APA, Harvard, Vancouver, ISO, and other styles

49

Hussein, Jabbar S., Abdulkadhim A. Salman, and Thmer R. Saeed. "Arabic speaker recognition using HMM." Indonesian Journal of Electrical Engineering and Computer Science 23, no. 2 (2021): 1212. http://dx.doi.org/10.11591/ijeecs.v23.i2.pp1212-1218.

Full text

Abstract:

In this paper, a new suggested system for speaker recognition by using hidden markov model (HHM) algorithm. Many researches have been written in this subject, especially by HMM. Arabic language is one of the difficult languages and the work with it is very little, also, the work has been done for text dependent system where HMM is very effective and the algorithm trained at the word level. One the problems in such systems is the noise, so we take it in consideration by adding additive white gaussian noise (AWGN) to the speech signals to see its effect. Here, we used HMM with new algorithm with one state, where two of these components, i.e. (π and A) are removed. This give extremely accelerates the training and testing stages of recognition speeds with lowest memory usage, as seen in the work. The results show an excellent outcome. 100% recognition rate for the tested data, about 91.6% recognition rate with AWGN noise.

APA, Harvard, Vancouver, ISO, and other styles

50

LASISI, HAMMED, FUNMILOLA ADEAGBO, and BOLATITO ADERINKOLA. "ENHANCEMENT OF GENERALISED SELECTIVE COMBINER USING COMBINED MODULATION SCHEMES OVER RAYLEIGH FADING CHANNEL." Journal of Engineering Studies and Research 28, no. 4 (2023): 71–77. http://dx.doi.org/10.29081/jesr.v28i4.008.

Full text

Abstract:

This research paper focused on the enhancement improvement of communication system using a combined modulation signal of Quadrature Amplitude Multiplexing and Orthogonal-frequency division multiplexing (OFDM) using a performance metrics of bit error rate (BER) and Signal to Noise Ratio (SNR) tested on a Rayleigh fading channel. The GSC is introduced at the receiving end to give a better received signal with in turn will result in better Quality of Service. The bit error rate (BER) performance of this type of systems are evaluated in the Rayleigh fading channel using Additive White Gaussian Noise (AWGN) channel as an ideal model.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Additive White Gaussian Noise (AWGN)'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles