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Journal articles on the topic 'Equalization enhanced phase noise'

Author: Grafiati

Published: 4 June 2021

Last updated: 8 February 2022

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1

Ho, Keang-Po, Alan Pak Tao Lau, and William Shieh. "Equalization-enhanced phase noise induced timing jitter." Optics Letters 36, no. 4 (February 15, 2011): 585. http://dx.doi.org/10.1364/ol.36.000585.

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2

Keang-Po Ho and W. Shieh. "Equalization-Enhanced Phase Noise in Mode-Division Multiplexed Systems." Journal of Lightwave Technology 31, no. 13 (July 2013): 2237–43. http://dx.doi.org/10.1109/jlt.2013.2264945.

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3

Qiu, Meng, Qunbi Zhuge, Mohammed Y. S. Sowailem, Thang M. Hoang, Mathieu Chagnon, Meng Xiang, Xingyu Zhou, Fangyuan Zhang, and David V. Plant. "Equalization-Enhanced Phase Noise in Stokes-Vector Direct Detection Systems." IEEE Photonics Journal 8, no. 6 (December 2016): 1–7. http://dx.doi.org/10.1109/jphot.2016.2628199.

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4

Kakkar, Aditya, Jaime Rodrigo Navarro, Richard Schatz, Hadrien Louchet, Xiaodan Pang, Oskars Ozolins, Gunnar Jacobsen, and Sergei Popov. "Comprehensive Study of Equalization-Enhanced Phase Noise in Coherent Optical Systems." Journal of Lightwave Technology 33, no. 23 (December 1, 2015): 4834–41. http://dx.doi.org/10.1109/jlt.2015.2491363.

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5

Xu, Tianhua, Gunnar Jacobsen, Sergei Popov, Jie Li, Ari T. Friberg, and Yimo Zhang. "Carrier phase estimation methods in coherent transmission systems influenced by equalization enhanced phase noise." Optics Communications 293 (April 2013): 54–60. http://dx.doi.org/10.1016/j.optcom.2012.11.090.

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6

Jin, Cenqin, Nikita A. Shevchenko, Zhe Li, Sergei Popov, Yunfei Chen, and Tianhua Xu. "Nonlinear Coherent Optical Systems in the Presence of Equalization Enhanced Phase Noise." Journal of Lightwave Technology 39, no. 14 (July 2021): 4646–53. http://dx.doi.org/10.1109/jlt.2021.3076067.

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7

Arnould, Aymeric, and Amirhossein Ghazisaeidi. "Equalization Enhanced Phase Noise in Coherent Receivers: DSP-Aware Analysis and Shaped Constellations." Journal of Lightwave Technology 37, no. 20 (October 15, 2019): 5282–90. http://dx.doi.org/10.1109/jlt.2019.2931841.

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8

Lau, Alan Pak Tao, Thomas Shun Rong Shen, William Shieh, and Keang-Po Ho. "Equalization-enhanced phase noise for 100Gb/s transmission and beyond with coherent detection." Optics Express 18, no. 16 (July 29, 2010): 17239. http://dx.doi.org/10.1364/oe.18.017239.

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9

Shieh, William, and Keang-Po Ho. "Equalization-enhanced phase noise for coherent-detection systems using electronic digital signal processing." Optics Express 16, no. 20 (September 19, 2008): 15718. http://dx.doi.org/10.1364/oe.16.015718.

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10

Delgado Mendinueta, José, Werner Klaus, Jun Sakaguchi, Satoshi Shinada, Hideaki Furukawa, Yoshinari Awaji, and Naoya Wada. "Numerical Investigation of the Equalization Enhanced Phase Noise Penalty for M-Quadrature Amplitude Modulation Formats in Short-Haul Few-Mode Fiber Transmission Systems with Time-Domain Equalization." Applied Sciences 8, no. 11 (November 7, 2018): 2182. http://dx.doi.org/10.3390/app8112182.

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The equalization enhanced phase noise (EEPN), caused by the interaction of the chromatic dispersion (CD) with the phase noise of the local oscillator (LO), has been extensively studied for single-mode optical communication systems. Few-mode fiber (FMF) transmission systems introduce a new channel impairment, the differential mode delay (DMD), which also creates EEPN and hence limits the maximum transmission distance of those systems. In this work, we numerically investigate the optical signal to noise ratio (OSNR) penalties caused by the EEPN in a 3-mode FMF transmission system at 25 GBd for quadrature phase-shift keying (QPSK), 16-quadrature amplitude modulation (QAM), 32-QAM and 64-QAM modulation formats when using the blind phase search (BPS) carrier phase recovery (CPR) algorithm, which has been demonstrated to be both robust and suitable for optical communication systems. Our numerical study assumes a short-span of FMF, modeled in the weakly-coupled regime, and includes two cases; the use of ideal mode-selective de/multiplexers at both ends of the FMF span (model A), and the use of ideal non-mode-selective de/multiplexers (model B). The results show that the EEPN has almost no effect in model A. However, EEPN produces a severe penalty in model B with the onset of the OSNR degradation starting for a DMD spread of the impulse response of about 100 symbols for all modulation formats investigated. The distribution ratio of the amount of phase noise between the transmitter and receiver lasers is also assessed for model B and we confirm that the degradation is mainly due to the phase noise of the LO.

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11

Kakkar, Aditya, Jaime Rodrigo Navarro, Richard Schatz, Xiaodan Pang, Oskars Ozolins, Hadrien Louchet, Gunnar Jacobsen, and Sergei Popov. "Equalization Enhanced Phase Noise in Coherent Optical Systems with Digital Pre- and Post-Processing." Photonics 3, no. 2 (March 26, 2016): 12. http://dx.doi.org/10.3390/photonics3020012.

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12

Ding, Jiazheng, Tianhua Xu, Cenqin Jin, Ziyihui Wang, Jian Zhao, and Tiegen Liu. "Impact of Equalization-Enhanced Phase Noise on Digital Nonlinearity Compensation in High-Capacity Optical Communication Systems." Sensors 20, no. 15 (July 26, 2020): 4149. http://dx.doi.org/10.3390/s20154149.

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Equalization-enhanced phase noise (EEPN) can severely degrade the performance of long-haul optical fiber transmission systems. In this paper, the impact of EEPN in Nyquist-spaced dual-polarization quadrature phase shift keying (DP-QPSK), dual-polarization 16-ary quadrature amplitude modulation (DP-16QAM), and DP-64QAM optical transmission systems is investigated considering the use of electrical dispersion compensation (EDC) and multi-channel digital backpropagation (MC-DBP). Our results demonstrate that full-field DBP (FF-DBP) is more susceptible to EEPN compared to single-channel and partial-bandwidth DBP. EEPN-induced distortions become more significant with the increase of the local oscillator (LO) laser linewidth, and this results in degradations in bit-error-rates (BERs), achievable information rates (AIRs), and AIR-distance products in optical communication systems. Transmission systems using higher-order modulation formats can enhance information rates and spectral efficiencies, but will be more seriously degraded by EEPN. It is found that degradations on AIRs, for the investigated FF-DBP schemes, in the DP-QPSK, the DP-16QAM, and the DP-64QAM systems are 0.07 Tbit/s, 0.11 Tbit/s, and 0.57 Tbit/s, respectively, due to the EEPN with an LO laser linewidth of 1 MHz. It is also seen that the selection of a higher-quality LO laser can significantly reduce the bandwidth requirement and the computational complexity in the MC-DBP.

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13

Xu, Tianhua, Cenqin Jin, Shuqing Zhang, Gunnar Jacobsen, Sergei Popov, Mark Leeson, and Tiegen Liu. "Phase Noise Cancellation in Coherent Communication Systems Using a Radio Frequency Pilot Tone." Applied Sciences 9, no. 21 (November 5, 2019): 4717. http://dx.doi.org/10.3390/app9214717.

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Long-haul optical fiber communication employing digital signal processing (DSP)-based dispersion compensation can be distorted by the phenomenon of equalization-enhanced phase noise (EEPN), due to the reciprocities between the dispersion compensation unit and the local oscillator (LO) laser phase noise (LPN). The impact of EEPN scales increases with the increase of the fiber dispersion, laser linewidths, symbol rates, signal bandwidths, and the order of modulation formats. In this work, the phase noise cancellation (PNC) employing a radio frequency (RF) pilot tone in coherent optical transmission systems has been investigated. A 28-Gsym/s QPSK optical transmission system with a significant EEPN has been implemented, where the carrier phase recovery (CPR) was realized using the one-tap normalized least-mean-square (NLMS) estimation and the differential phase detection (DPD), respectively. It is shown that the RF pilot tone can entirely eliminate the LPN and efficiently suppress the EEPN when it is applied prior to the CPR.

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14

Zhuge, Qunbi, Xian Xu, Ziad A. El-Sahn, Mohammad E. Mousa-Pasandi, Mohamed Morsy-Osman, Mathieu Chagnon, Meng Qiu, and David V. Plant. "Experimental investigation of the equalization-enhanced phase noise in long haul 56 Gbaud DP-QPSK systems." Optics Express 20, no. 13 (June 7, 2012): 13841. http://dx.doi.org/10.1364/oe.20.013841.

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15

Xu, Tianhua, Gunnar Jacobsen, Sergei Popov, Jie Li, Sergey Sergeyev, Ari T. Friberg, and Yimo Zhang. "Analytical BER performance in differential n-PSK coherent transmission system influenced by equalization enhanced phase noise." Optics Communications 334 (January 2015): 222–27. http://dx.doi.org/10.1016/j.optcom.2014.07.094.

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16

Asif Khan, Muhammad Kamal, Farman Ali, Muhammad Irfan, Fazal Muhammad, Faisal Althobiani, Asar Ali, Suliman Khan, Saifur Rahman, Grzegorz Perun, and Adam Glowacz. "Mitigation of Phase Noise and Nonlinearities for High Capacity Radio-over-Fiber Links." Electronics 10, no. 3 (February 1, 2021): 345. http://dx.doi.org/10.3390/electronics10030345.

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Radio-over-fiber (RoF) links successfully provide high data rates and bandwidth capacity with a low complexity system architecture, as compared to its counterpart digital-RoF. In addition, the compound of quadrature amplitude modulation (QAM) and orthogonal frequency division multiplexed (OFDM) modulation schemes further enhance the process of these achievements. However, high data rates and bandwidth-capacity-supported RoF links face nonlinearities (NLs), linear distortions (LDs), and phase noise challenges that degrade the reliability of communication networks (CNs). Therefore, in this paper, to suppress NLs, LDs, and phase noise, next generation cloud radio access networks (CRANs) are investigated using RoF links and wavelength division multiplexing (WDM) methodology based on 16, 32, and 64 QAM-OFDM modulation schemes. The receiver of the proposed framework is designed, applying an improved digital signal processing (DSP) system that includes overlap frequency domain equalization (OFDE), a synchronization process, and time domain equalization (TDE). Theoretical and simulation models are organized for estimating the proposed RoF link with the aid of different values of transmission ranges, input power, output power, bit rate, bits per symbol, channel spacing, and the number of users. The fitness of the model matches that of existing approaches.

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17

Xu, Tianhua, Gunnar Jacobsen, Sergei Popov, Jie Li, Sergey Sergeyev, Ari T. Friberg, Tiegen Liu, and Yimo Zhang. "Analysis of chromatic dispersion compensation and carrier phase recovery in long-haul optical transmission system influenced by equalization enhanced phase noise." Optik 138 (June 2017): 494–508. http://dx.doi.org/10.1016/j.ijleo.2017.03.024.

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18

Borra, Subba Reddy, G. Jagadeeswar Reddy, and E. Sreenivasa Reddy. "An Efficient Fingerprint Identification using Neural Network and BAT Algorithm." International Journal of Electrical and Computer Engineering (IJECE) 8, no. 2 (April 1, 2018): 1194. http://dx.doi.org/10.11591/ijece.v8i2.pp1194-1213.

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The uniqueness, firmness, public recognition, and its minimum risk of intrusion made fingerprint is an expansively used personal authentication metrics. Fingerprint technology is a biometric technique used to distinguish persons based on their physical traits. Fingerprint based authentication schemes are becoming increasingly common and usage of these in fingerprint security schemes, made an objective to the attackers. The repute of the fingerprint image controls the sturdiness of a fingerprint authentication system. We intend for an effective method for fingerprint classification with the help of soft computing methods. The proposed classification scheme is classified into three phases. The first phase is preprocessing in which the fingerprint images are enhanced by employing median filters. After noise removal histogram equalization is achieved for augmenting the images. The second stage is the feature Extraction phase in which numerous image features such as Area, SURF, holo entropy, and SIFT features are extracted. The final phase is classification using hybrid Neural for classification of fingerprint as fake or original. The neural network is unified with BAT algorithm for optimizing the weight factor.

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19

Meera, R., P. Anandan, and N. Nandhagopal. "A New Meta Heuristic Based Segmentation for MRI Image." Journal of Medical Imaging and Health Informatics 10, no. 7 (July 1, 2020): 1525–33. http://dx.doi.org/10.1166/jmihi.2020.3048.

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An automated brain tumor segmentation and detection have huge importance in the diagnostics of medical field as it renders information about functional structures in addition to the probable abnormal tissue required for surgical planning. However, it is still a problem due to low contrast and poorly-specified boundaries and accuracy issue. Hence, Refined Migrating Birds Optimization (RMBO) algorithm is introduced for automatic tumor segmentation that gets over the disadvantage of classical metaheuristic segmentation techniques. The RMBO helps in improving both migration and position update steps which includes three phases. First phase starts from Preprocessing, film artifacts and unnecessary areas (skull) of MRI images are eliminated with the help of enhanced tracking algorithm. Next and second phase being the procedure of eliminating the noises employing Anisotropic Filtering and contrast enhancement is carried out with the help of histogram equalization. Finally segmentation is performed employing RMBO. The novel algorithm operates on the image pixels information along with regions/neighborhood map to generate a contextual area where the merging is possible. With the RMBO algorithm, MRI of brain images are segmented and the results are analyzed through the comparison of the existing techniques viz., Particle Swarm Optimization (PSO), Genetic algorithms.

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20

Cheng, Longwang, Li Zhou, Boon-Chong Seet, Wei Li, Dongtang Ma, and Jibo Wei. "Efficient Physical-Layer Secret Key Generation and Authentication Schemes Based on Wireless Channel-Phase." Mobile Information Systems 2017 (2017): 1–13. http://dx.doi.org/10.1155/2017/7393526.

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Exploiting the inherent physical properties of wireless channels to complement or enhance the traditional security mechanisms has attracted prominent attention recently. However, the existing secret key generation schemes suffer from miscellaneous extracting procedure. Many PHY-layer authentication schemes assume that the knowledge of the shared key is preknown. In this paper, we propose PHY-layer secret key generation and authentication schemes for orthogonal frequency-division multiplexing (OFDM) systems. In the secret key generation scheme, to simplify the extracting procedure, only one legitimate party is chosen to probe the channel and quantize the measurements to obtain the preliminary key. The preliminary key is masked by the channel-phase after the mapping and before equalization and distributed to the other party. The final shared key is used for the PHY-layer authentication scheme in which random signals and the shared key masked by the channel-phase are exchanged at the PHY-layer. Then, a binary hypothesis test is formulated for authentication. Simulation results show that the proposed secret key generation scheme outperforms the existing schemes. For the PHY-layer authentication scheme, it is immune to various passive and active attacks and a high successful authentication rate is acquired even at low signal-to-noise ratio region.

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21

Liao, Xichang, and Yingke Lei. "Modified Variable Step Size FLOM-CMA Based on Lorentzian Function under Impulse Noise." MATEC Web of Conferences 232 (2018): 04061. http://dx.doi.org/10.1051/matecconf/201823204061.

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Aiming at the problem that the traditional equalization algorithm under impulse noise is difficult to suppress impulse noise and achieve equalization, a new modified variable step size FLOM-CMA algorithm based on Lorentzian function is proposed in this paper. The proposed algorithm has modified the cost function to made full use of the phase information of signal to correct the phase rotation. Also, by adjusting the FLOM of cost function, that impulse noise is restrained effectively. Furthermore, the Lorentzian function is use to update the step size to make sure it is is appropriate for each equalization point. Simulation experiments show that, compared with FLOM-CMA and VS-FLOM-CMA, the proposed algorithm that the proposed algorithm achieves higher convergence accuracy with similar convergence speed. And under different impulse noise conditions, the robustness of the algorithm is better.

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22

Hao, Shilei, Tongning Hu, and Qun Jane Gu. "Time-Amplifier Enhanced Phase Noise Filter." IEEE Microwave and Wireless Components Letters 28, no. 8 (August 2018): 699–701. http://dx.doi.org/10.1109/lmwc.2018.2845941.

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23

Neiman, Alexander, Alexander Silchenko, Vadim Anishchenko, and Lutz Schimansky-Geier. "Stochastic resonance: Noise-enhanced phase coherence." Physical Review E 58, no. 6 (December 1, 1998): 7118–25. http://dx.doi.org/10.1103/physreve.58.7118.

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24

Zhao, Meng Ling, and Min Xia Jiang. "Research on Enhanced of Mine-Underground Picture." Advanced Materials Research 490-495 (March 2012): 548–52. http://dx.doi.org/10.4028/www.scientific.net/amr.490-495.548.

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Because of the based on S3C6410 Field information recorder mine- underground non-uniform illumination and mine- underground non-uniform illumination that a large of noise collected and transferred,image is low contrast ,dim and dark. Based on the theory of Donoho's wavelet threshold denoising, several typical wavelet threshold denoising methods are compared.the best denoising effect of peak signal to noise ratio is obtained. The image enhancement method that combination of the adaptive thresholding denoising and histogram equalization is proposed. The experiment result shows that the method has a good denoising performance, which removed the readout noise of CCD Camera,at the same time, image quality is improved .So the wavelet enhancement in image processing of mine- underground can improve image quality.

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25

Siddiqi, Ayesha Amir, Ghous Bakhsh Narejo, Mashal Tariq, and Adnan Hashmi. "INVESTIGATION OF HISTOGRAM EQUALIZATION FILTER FOR CT SCAN IMAGE ENHANCEMENT." Biomedical Engineering: Applications, Basis and Communications 31, no. 05 (September 9, 2019): 1950038. http://dx.doi.org/10.4015/s1016237219500388.

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This piece of work investigates the application of histogram equalization method to clinical images for noise removal and efficient image enhancement without any information loss. Computed tomographic (CT) images of the abdomen bearing liver tumour are kept under study. Liver exhibits heterogeneous combination of intensities which makes it a challenging task to enhance the liver tumour embedded in the image. Distortion occurs due to the presence of quantum noise in the CT scans and important information of the image is suppressed. The methodology adopted in this paper comprises of two stages. Initially pixel based intensity transformation is adopted for de-noising the background of the image by the selection of appropriate threshold levels. The resultant image gives a noise free background and the foreground features are enhanced. In the next stage histogram equalization filters are applied to the transformed image. The equalization method which gives uniform image enhancement with lesser mean square error (MSE) and increased peak signal to noise ratio (PSNR) is supposed to be an effective method for efficient enhancement of the images. This study deals with the application of histogram equalization methods to CT images which can aid the radiologists for better visualization and diagnosis of the disease.

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26

Chang, Yao-Jen, and Chia-Lu Ho. "SCFNN-Based Decision Feedback Equalization Robust to Frequency Offset and Phase Noise." Circuits, Systems, and Signal Processing 30, no. 5 (January 8, 2011): 929–40. http://dx.doi.org/10.1007/s00034-010-9258-5.

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27

Baqer, Ismail Sh. "Image Quality Enhancing by Efficient Histogram Equalization." Wasit Journal of Engineering Sciences 2, no. 2 (October 2, 2014): 47–58. http://dx.doi.org/10.31185/ejuow.vol2.iss2.29.

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A two Level Image Quality enhancement is proposed in this paper. In the first level, Dualistic Sub-Image Histogram Equalization DSIHE method decomposes the original image into two sub-images based on median of original images. The second level deals with spikes shaped noise that may appear in the image after processing. We presents three methods of image enhancement GHE, LHE and proposed DSIHE that improve the visual quality of images. A comparative calculations is being carried out on above mentioned techniques to examine objective and subjective image quality parameters e.g. Peak Signal-to-Noise Ratio PSNR values, entropy H and mean squared error MSE to measure the quality of gray scale enhanced images. For handling gray-level images, convenient Histogram Equalization methods e.g. GHE and LHE tend to change the mean brightness of an image to middle level of the gray-level range limiting their appropriateness for contrast enhancement in consumer electronics such as TV monitors. The DSIHE methods seem to overcome this disadvantage as they tend to preserve both, the brightness and contrast enhancement. Experimental results show that the proposed technique gives better results in terms of Discrete Entropy, Signal to Noise ratio and Mean Squared Error values than the Global and Local histogram-based equalization methods

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28

Haowei Wu, Shizhong Yang, Jinglan Ou, and Lisheng Yang. "Phase Noise Estimation and Equalization for OFDM Systems Based on Interpolation of Common Phase Error." International Journal of Digital Content Technology and its Applications 5, no. 9 (September 30, 2011): 323–30. http://dx.doi.org/10.4156/jdcta.vol5.issue9.36.

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29

Zhuge, Qunbi, Mohamed Morsy-Osman, and David V. Plant. "Analysis of dispersion-enhanced phase noise in." Optics Express 19, no. 24 (November 10, 2011): 24030. http://dx.doi.org/10.1364/oe.19.024030.

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30

Neiman, Alexander, Lutz Schimansky-Geier, Ann Cornell-Bell, and Frank Moss. "Noise-Enhanced Phase Synchronization in Excitable Media." Physical Review Letters 83, no. 23 (December 6, 1999): 4896–99. http://dx.doi.org/10.1103/physrevlett.83.4896.

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31

Dhawan, Divya, and Neena Gupta. "Performance Analysis of Laser Phase Noise Compensated COOFDM System." Journal of Optical Communications 41, no. 4 (April 28, 2020): 445–51. http://dx.doi.org/10.1515/joc-2018-0002.

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AbstractOrthogonal Frequency Division Multiplexing along with the coherent detection and spectrally efficient modulation formats is a promising solution for long haul and high speed communication systems. Although they offer significant advantages which make them suitable for high speed and long haul communication systems they all are susceptible to phase noise. In this paper a combination of RF-pilot-based approach followed by pilot-based equalization approach is used for laser phase noise compensation. The various parameters such as drive voltage, bias voltage and extinction ratio are optimized to get the optimum performance from the proposed scheme. The designed system is then analyzed in terms of Symbol Error Rate (SER), constellation diagrams and error vector magnitude using various types of Quadrature Amplitude Modulation (QAM) formats.

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32

Hao, Ming, Lianshan Yan, Anlin Yi, Lin Jiang, Yan Pan, Wei Pan, and Bin Luo. "Enhanced frequency-domain fractionally spaced equalization for coherent optical transmission system with colored noise." Optical Engineering 56, no. 6 (June 28, 2017): 066116. http://dx.doi.org/10.1117/1.oe.56.6.066116.

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33

Suyama, Satoshi, Junichi Onodera, Hiroshi Suzuki, and Kazuhiko Fukawa. "Decision-directed phase noise compensation for millimeter-wave single carrier systems with iterative frequency-domain equalization." International Journal of Microwave and Wireless Technologies 2, no. 3-4 (July 8, 2010): 399–408. http://dx.doi.org/10.1017/s1759078710000516.

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This paper proposes a receiver that repeats iterative frequency-domain equalization (FDE) and decision-directed phase noise compensation (DD-PNC) to alleviate degradation due to the phase noise for millimeter-wave single carrier (SC) systems. High bit-rate SC-FDE transceivers based on the single-chip Si RF-CMOS IC technology in the 60-GHz millimeter-wave band have been extensively studied for wireless personal area network (WPAN) systems, and the relatively large phase noise in a phase-locked loop (PLL) synthesizer severely degrades transmission performance. In an initial processing of the proposed receiver, a cyclic prefix (CP)-based phase noise compensator (CP-PNC) removes the phase noise from a time-domain received signal by using CP, which is known to the receiver, and the channel is equalized by the iterative FDE using the conventional minimum mean-square-error (MMSE) weight. In an iterative processing, DD-PNC estimates the phase noise each symbol by exploiting an output of a channel decoder, and then compensates the time-domain received signal for the phase noise by using the estimate. In order to equalize the compensated received signal, the iterative FDE performs both the MMSE filtering and residual inter-symbol interference cancelation using the decoder output. Computer simulations following the 60-GHz WPAN standard demonstrate that in the 64QAM with the coding rate of 3/4, the proposed receiver with three iterations can drastically remove the phase noise of −85 dBc/Hz at 1 MHz offset, and that it can achieve excellent transmission performance.

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34

Rickett, J. E., and D. E. Lumley. "Cross‐equalization data processing for time‐lapse seismic reservoir monitoring: A case study from the Gulf of Mexico." GEOPHYSICS 66, no. 4 (July 2001): 1015–25. http://dx.doi.org/10.1190/1.1487049.

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Nonrepeatable noise, caused by differences in vintages of seismic acquisition and processing, can often make comparison and interpretation of time‐lapse 3‐D seismic data sets for reservoir monitoring misleading or futile. In this Gulf of Mexico case study, the major causes of nonrepeatable noise in the data sets are the result of differences in survey acquisition geometry and binning, temporal and spatial amplitude gain, wavelet bandwidth and phase, differential static time shifts, and relative mispositioning of imaged reflection events. We attenuate these acquisition and processing differences by developing and applying a cross‐equalization data processing flow for time‐lapse seismic data. The cross‐equalization flow consists of regridding the two data sets to a common grid; applying a space and time‐variant amplitude envelope balance; applying a first pass of matched filter corrections for global amplitude, bandwidth, phase and static shift corrections, followed by a dynamic warp to align mispositioned events; and, finally, running a second pass of constrained space‐variant matched filter operators. Difference sections obtained by subtracting the two data sets after each step of the cross‐equalization processing flow show a progressive reduction of nonrepeatable noise and a simultaneous improvement in time‐lapse reservoir signal.

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35

Landini, M., M. Fattori, L. Pezzè, and A. Smerzi. "Phase-noise protection in quantum-enhanced differential interferometry." New Journal of Physics 16, no. 11 (November 26, 2014): 113074. http://dx.doi.org/10.1088/1367-2630/16/11/113074.

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36

Samara, Lutfi, Abubakr O. Al-Abbasi, Ridha Hamila, and Naofal Al-Dhahir. "Reduced-complexity sparsity-aware joint phase noise mitigation and channel equalization in OFDM receivers." Physical Communication 30 (October 2018): 50–57. http://dx.doi.org/10.1016/j.phycom.2018.07.001.

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37

Xu, Tianhua, Gunnar Jacobsen, Sergei Popov, Jie Li, Ari T. Friberg, and Yimo Zhang. "Analytical estimation of phase noise influence in coherent transmission system with digital dispersion equalization." Optics Express 19, no. 8 (April 6, 2011): 7756. http://dx.doi.org/10.1364/oe.19.007756.

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38

Mun, Kyoung-Hak, Sang-Min Jung, Soo-Min Kang, and Sang-Kook Han. "Channel Equalization and Phase Noise Compensation Free DAPSK-OFDM Transmission for Coherent PON System." IEEE Photonics Journal 9, no. 5 (October 2017): 1–9. http://dx.doi.org/10.1109/jphot.2017.2729579.

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39

Li, Fanxing, Wei Yan, Fupin Peng, Simo Wang, and Jialin Du. "Enhanced Phase Retrieval Method Based on Random Phase Modulation." Applied Sciences 10, no. 3 (February 10, 2020): 1184. http://dx.doi.org/10.3390/app10031184.

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The phase retrieval method based on random phase modulation can wipe out any ambiguity and stagnation problem in reconstruction. However, the two existing reconstruction algorithms for the random phase modulation method are suffering from problems. The serial algorithm from the spread-spectrum phase retrieval method can realize rapid convergence but has poor noise immunity. Although there is a parallel framework that can suppress noise, the convergence speed is slow. Here, we propose a random phase modulation phase retrieval method based on a serial–parallel cascaded reconstruction framework to simultaneously achieve quality imaging and rapid convergence. The proposed serial–parallel cascaded method uses the phased result from the serial algorithm to serve as the initialization of the subsequent parallel process. Simulations and experiments demonstrate that the superiorities of both serial and parallel algorithms are fetched by the proposed serial–parallel cascaded method. In the end, we analyze the effect of iteration numbers from the serial process on the reconstruction performance to find the optimal allocation scope of iteration numbers.

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Arora, H., N. Klemmer, J. C. Morizio, and P. D. Wolf. "Enhanced phase noise modeling of fractional-N frequency synthesizers." IEEE Transactions on Circuits and Systems I: Regular Papers 52, no. 2 (February 2005): 379–95. http://dx.doi.org/10.1109/tcsi.2004.841594.

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Girija, S. P., and Rameshwar Rao. "Fractional weighted ZF equalizer: A novel approach for channel equalization in MIMO-OFDM system under impulse noise environment." Communications in Science and Technology 6, no. 1 (July 27, 2021): 1–10. http://dx.doi.org/10.21924/cst.6.1.2021.224.

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Impulse noise is the major factor degrading the performance of the wireless system, imposing the need for the impulse noise mitigation strategy. Mainly, in the multiple-input multiple-output (MIMO) and orthogonal frequency-division multiplexing (OFDM) system contaminated with the impulse noise creates a major impact in the performance as the conventional zero-forcing (ZF) equalizer as there is no satisfactory results. Thus, the paper concentrates on the impulse noise mitigation strategy based on the fractional weighed zero-forcing (FWZF) equalizer, which is the integration of the fractional concept in the Zero-Forcing equalizer. The noise impacts in the MIMO-OFDM system are minimized and the performance is enhanced due to the usage of the fractional theory in the ZF equalizer as the equalization values of the previous instances are interpreted for the formulation of the effective equalization value in the current instance of the ZF equalizer. The performance of the methods is done based on the valuation metrics, Bit Error Rate (BER), Mean Square Error (MSE), and Symbol Error Rate (SER) with respect to the Signal-to-Noise Ratio (SNR) and dissimilar antenna array size. It is found that the proposed Fractional Weighed Zero-Forcing equalizer outperformed the existing methods with a minimal BER and SER of 0.063, and 0.1038 while analyzing the methods in the Rayleigh environment.

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Wang, Wei, Zhongyong Wang, Chuanzong Zhang, Qinghua Guo, Peng Sun, and Xingye Wang. "A BP–MF–EP Based Iterative Receiver for Joint Phase Noise Estimation, Equalization, and Decoding." IEEE Signal Processing Letters 23, no. 10 (October 2016): 1349–53. http://dx.doi.org/10.1109/lsp.2016.2593917.

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Jenq-Tay Yuan, Jen-Hung Chao, and Tzu-Chao Lin. "Effect of Channel Noise on Blind Equalization and Carrier Phase Recovery of CMA and MMA." IEEE Transactions on Communications 60, no. 11 (November 2012): 3274–85. http://dx.doi.org/10.1109/tcomm.2012.082712.110597.

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Rao, Gutta Srinivasa, and Atluri Srikrishna. "Image Pixel Contrast Enhancement Using Enhanced Multi Histogram Equalization Method." Ingénierie des systèmes d information 26, no. 1 (February 28, 2021): 95–101. http://dx.doi.org/10.18280/isi.260110.

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Image Enhancement methods produce various sorts of problems, for example, unnatural impacts, over-improvement, and these downsides become increasingly unmistakable in improving dull Images. Histogram Equalization (HE) method is a straightforward and generally utilized Image contrast enhancement procedure. The fundamental task of HE is it changes the contrast of the Image. To perform this task, different HE techniques have been proposed. These techniques protect the brightness or contrast on the final Image that doesn't have a characteristic look. To overcome the drawbacks of HE, Enhanced Multi Histogram Equalization (EMHE) technique is proposed, which divide the Image into a few sub images and again these sub images are divided into sub-images, and traditional HE strategy is applied to each sub Image for getting better results. The improvement is brought about by repetitive data present in sub-pixel moves between relating Lightroom (LR) Images of a similar scene. The principal phase of the development incorporates Image enrollment of LR Images utilizing known parameters and geo-referencing methods for manufactured and genuine information individually. The proposed development of M-HE Images has been assessed on the LR Images obtained from satellite Image datasets to exhibit the clarity of the images by enhancing the contrast on the poor lighting images.

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Wu, Shibin, Shaode Yu, Yuhan Yang, and Yaoqin Xie. "Feature and Contrast Enhancement of Mammographic Image Based on Multiscale Analysis and Morphology." Computational and Mathematical Methods in Medicine 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/716948.

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A new algorithm for feature and contrast enhancement of mammographic images is proposed in this paper. The approach bases on multiscale transform and mathematical morphology. First of all, the Laplacian Gaussian pyramid operator is applied to transform the mammography into different scale subband images. In addition, the detail or high frequency subimages are equalized by contrast limited adaptive histogram equalization (CLAHE) and low-pass subimages are processed by mathematical morphology. Finally, the enhanced image of feature and contrast is reconstructed from the Laplacian Gaussian pyramid coefficients modified at one or more levels by contrast limited adaptive histogram equalization and mathematical morphology, respectively. The enhanced image is processed by global nonlinear operator. The experimental results show that the presented algorithm is effective for feature and contrast enhancement of mammogram. The performance evaluation of the proposed algorithm is measured by contrast evaluation criterion for image, signal-noise-ratio (SNR), and contrast improvement index (CII).

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Zhang, Chang Jiang, and Yan Zhou. "Adaptive Infrared Image Enhancement by Combining Differential Evolution with Stationary Wavelet Transformation." Applied Mechanics and Materials 58-60 (June 2011): 2273–78. http://dx.doi.org/10.4028/www.scientific.net/amm.58-60.2273.

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Considering noise and low contrast of infrared image，an efficient nonlinear adaptive enhancement algorithm，which is based on differential evolution (DE)algorithm and stationary wavelet transform (SWT)，is proposed. Evaluation function is constructed by combing information entropy，signal-noise-ratio with standard deviation of enhanced image. A nonlinear transformation function is designed to enhance the contrast of the infrared image. The optimal transformation parameters are determined by combing DE algorithm with the constructed evaluation function. The proposed algorithm can efficiently enhance the contrast of the infrared image while have a good robust to noise. Experimental results show that the proposed algorithm is better than multi-scale nonlinear enhancement algorithm，stationary wavelet nonlinear enhancement algorithm and histogram equalization algorithm in overall performance.

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Wang, Maosheng, Zhonghuai Hou, and Houwen Xin. "Internal noise-enhanced phase synchronization of coupled chemical chaotic oscillators." Journal of Physics A: Mathematical and General 38, no. 1 (December 9, 2004): 145–52. http://dx.doi.org/10.1088/0305-4470/38/1/010.

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Li, Tingting, Kun-Shan Chen, and John-Sen Lee. "Enhanced Interferometric Phase Noise Filtering of the Refined InSAR Filter." IEEE Geoscience and Remote Sensing Letters 17, no. 9 (September 2020): 1528–32. http://dx.doi.org/10.1109/lgrs.2019.2951635.

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Hauth, Christopher F., Simon C. Berning, Birger Kollmeier, and Thomas Brand. "Modeling Binaural Unmasking of Speech Using a Blind Binaural Processing Stage." Trends in Hearing 24 (January 2020): 233121652097563. http://dx.doi.org/10.1177/2331216520975630.

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The equalization cancellation model is often used to predict the binaural masking level difference. Previously its application to speech in noise has required separate knowledge about the speech and noise signals to maximize the signal-to-noise ratio (SNR). Here, a novel, blind equalization cancellation model is introduced that can use the mixed signals. This approach does not require any assumptions about particular sound source directions. It uses different strategies for positive and negative SNRs, with the switching between the two steered by a blind decision stage utilizing modulation cues. The output of the model is a single-channel signal with enhanced SNR, which we analyzed using the speech intelligibility index to compare speech intelligibility predictions. In a first experiment, the model was tested on experimental data obtained in a scenario with spatially separated target and masker signals. Predicted speech recognition thresholds were in good agreement with measured speech recognition thresholds with a root mean square error less than 1 dB. A second experiment investigated signals at positive SNRs, which was achieved using time compressed and low-pass filtered speech. The results demonstrated that binaural unmasking of speech occurs at positive SNRs and that the modulation-based switching strategy can predict the experimental results.

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Lovstedt, Stephan P., Jared K. Thomas, Scott D. Sommerfeldt, and Jonathan D. Blotter. "Genetic Algorithm Applied to the Eigenvalue Equalization Filtered-x LMS Algorithm (EE-FXLMS)." Advances in Acoustics and Vibration 2008 (May 8, 2008): 1–12. http://dx.doi.org/10.1155/2008/791050.

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The FXLMS algorithm, used extensively in active noise control (ANC), exhibits frequency-dependent convergence behavior. This leads to degraded performance for time-varying tonal noise and noise with multiple stationary tones. Previous work by the authors proposed the eigenvalue equalization filtered-x least mean squares (EE-FXLMS) algorithm. For that algorithm, magnitude coefficients of the secondary path transfer function are modified to decrease variation in the eigenvalues of the filtered-x autocorrelation matrix, while preserving the phase, giving faster convergence and increasing overall attenuation. This paper revisits the EE-FXLMS algorithm, using a genetic algorithm to find magnitude coefficients that give the least variation in eigenvalues. This method overcomes some of the problems with implementing the EE-FXLMS algorithm arising from finite resolution of sampled systems. Experimental control results using the original secondary path model, and a modified secondary path model for both the previous implementation of EE-FXLMS and the genetic algorithm implementation are compared.

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