Optics and Laser Technology最新文献_第4页

Efficient interpolation-based and terrain-adaptive hierarchical filter for ultra-large-scale point cloud over complex landscapes

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2025-03-27 DOI: 10.1016/j.optlastec.2025.112860

Chuanfa Chen , Lianzhong Xu , Jinda Hao , Yanyan Li , Dongxing Chen

{"title":"Efficient interpolation-based and terrain-adaptive hierarchical filter for ultra-large-scale point cloud over complex landscapes","authors":"Chuanfa Chen , Lianzhong Xu , Jinda Hao , Yanyan Li , Dongxing Chen","doi":"10.1016/j.optlastec.2025.112860","DOIUrl":"10.1016/j.optlastec.2025.112860","url":null,"abstract":"<div><div>Complex landscapes, typically characterized by outliers, objects with diverse structures, vegetation on steep slopes, and terrain discontinuities, pose significant challenges to traditional filtering methods, especially when processing ultra-large-scale point clouds. To address these challenges, this paper proposes an efficient interpolation-based and terrain-adaptive hierarchical filtering method. Specifically, a hybrid algorithm combining a moving-window detector with robust surface fitting is developed to optimize the selection of initial ground seeds. Subsequently, a weighted finite-difference-based Thin Plate Spline (TPS) method is introduced to generate reference ground surfaces, thereby improving computational efficiency and mitigating the impact of misclassified object points. Finally, a terrain-adaptive filtering threshold incorporating different orders of terrain roughness is designed to accurately extract ground points near terrain discontinuities. To evaluate the proposed method, extensive experiments were conducted on the ISPRS benchmark samples and the ultra-large-scale OpenGF dataset. Results demonstrate that our method achieves an average Kappa coefficient of 92.3% across all 15 ISPRS samples, outperforming 24 state-of-the-art filtering methods published since 2010. On the OpenGF dataset, the proposed method surpasses five classical filters, reducing the average total error by 34.1%–77.4% and improving the average Kappa coefficient by 2.8%–21.7%. Overall, this framework provides a robust solution for filtering ultra-large-scale point clouds in complex landscapes.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"187 ","pages":"Article 112860"},"PeriodicalIF":4.6,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dimensionality reduction calibration of a robotic grinding head’s 3D coordinate system using a 1D laser sensor

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2025-03-27 DOI: 10.1016/j.optlastec.2025.112831

Baichun Li, Zhi Li, Chang Ge, Chang Liu, Sujing Qin, Zhenpeng He

{"title":"Dimensionality reduction calibration of a robotic grinding head’s 3D coordinate system using a 1D laser sensor","authors":"Baichun Li, Zhi Li, Chang Ge, Chang Liu, Sujing Qin, Zhenpeng He","doi":"10.1016/j.optlastec.2025.112831","DOIUrl":"10.1016/j.optlastec.2025.112831","url":null,"abstract":"<div><div>The demand for highly accessible grinding in confined spaces, such as integral blisks, has driven research and applications in robotic grinding and polishing using a grinding head. Achieving high-precision and low-cost calibration of the grinding head is a primary challenge. Consequently, a novel dimensionality reduction calibration method is proposed. This method employs a 1D point laser displacement sensor to calibrate the 3D grinding head coordinate system. Firstly, a hand-eye calibration method for the sensor is proposed. The “fitting and one-step rotation method” determines the rotation axis and angle through the fitting, followed by one-step rotation to make the flange plane parallel to the laser emission plane, thereby completing the sensor orientation calibration. The “two-step rotation method” aligns the flange center with the measurement origin of the sensor to complete the sensor position calibration. Subsequently, the 3D grinding head coordinate system is calibrated with the pre-calibrated sensor as an intermediary. The “two-step translation method” makes the grinding head’s end face parallel to the laser emission plane, completing the grinding head’s orientation calibration. The “spatial three-point method” aligns the grinding head center with the sensor’s measurement origin, completing the grinding head’s position calibration. Finally, the experiments demonstrate that the precision of hand-eye calibration can be maintained within 0.178 mm and 0.6°, while the accuracy of the grinding head calibration is within 0.08 mm and 0.4°. The calibration method provides high precision, low cost, and reliable stability while supporting programming for rapid calibration, thereby facilitating the high-precision automation of robotic grinding and polishing.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"187 ","pages":"Article 112831"},"PeriodicalIF":4.6,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental investigation on crack evolution and separation strength in 4H-SiC slicing by sub-nanosecond laser

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2025-03-27 DOI: 10.1016/j.optlastec.2025.112826

Heng Wang , Qiang Cao , Tianhao Wu , Zhenzhong Wang , Yuting Hou , Sheng Peng , Du Wang

{"title":"Experimental investigation on crack evolution and separation strength in 4H-SiC slicing by sub-nanosecond laser","authors":"Heng Wang , Qiang Cao , Tianhao Wu , Zhenzhong Wang , Yuting Hou , Sheng Peng , Du Wang","doi":"10.1016/j.optlastec.2025.112826","DOIUrl":"10.1016/j.optlastec.2025.112826","url":null,"abstract":"<div><div>Compared with wire sawing technology, laser slicing technology has been considered a more advantageous technique for slicing SiC wafers with the advantages of small kerf loss and high efficiency. How to realize laser slicing of SiC with low separation strength and low damage remains a current challenge. In this paper, semi-insulating SiC slices with a separation strength of only 0.04 MPa and a damage layer thickness of only 5 μm were realized using a sub-nanosecond laser. The crack nucleation mechanism was delved into by analyzing the morphology and composition of the modified layer, and the influence of laser processing parameters on crack propagation was systematically studied. Tensile tests were performed on samples with varying crack states to uncover the relationship between crack state and separation strength. The results indicate that the damage layer comprises graphite and amorphous silicon, with secondary processing being the key factor in the nucleation of cracks on the cleavage surface (0 0 0 1) plane. Separation strength minimizes when the interval matches the crack-tip stress field boundary. And the feasibility of large-area processing was verified on 6-inch ingots.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"187 ","pages":"Article 112826"},"PeriodicalIF":4.6,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimization and arbitrary frequency stabilization of probe laser based on a transfer cavity in SERF Co-Magnetometer

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2025-03-27 DOI: 10.1016/j.optlastec.2025.112875

Zhaoyang Cao , Xinxiu Zhou , Wenlei Zhao , Jingcheng Shang

{"title":"Optimization and arbitrary frequency stabilization of probe laser based on a transfer cavity in SERF Co-Magnetometer","authors":"Zhaoyang Cao , Xinxiu Zhou , Wenlei Zhao , Jingcheng Shang","doi":"10.1016/j.optlastec.2025.112875","DOIUrl":"10.1016/j.optlastec.2025.112875","url":null,"abstract":"<div><div>We demonstrate an arbitrary frequency stabilization technology that can ensure both the frequency stability and tunability of the probe laser in a spin-exchange relaxation-free (SERF) atomic co-magnetometer at the frequencies far from the atomic resonance line. In theory, the non-negligible coupling between the cavity length locking and the locked laser frequency is identified and a transfer function model for the frequency stabilization system is established. The modulation multiplexing cavity length locking method and dual-phase modulation sideband locking method are designed to overcome the limitations of traditional transfer cavity method, including noise coupling and insufficient frequency tunability. Experimental results show that at a frequency far from the atomic resonance line, the Allan deviation after the frequency locking reached 8.223 × 10<sup>−11</sup> for an averaging time of 10<sup>3</sup> s, which is lower by approximately two orders of magnitude than the frequency instability of free running laser. The research work is of great significance to improve the frequency stability, frequency tunability, cost-effectiveness, and compactness of the far-detuned probe laser in a SERF atomic co-magnetometer.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"187 ","pages":"Article 112875"},"PeriodicalIF":4.6,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143714682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improved wavefront reconstruction for Shack–Hartmann wavefront sensor in the presence of shock-related distortions

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2025-03-27 DOI: 10.1016/j.optlastec.2025.112764

Ethan D. Chu, Timothy J. Bukowski, Stanislav Gordeyev

{"title":"Improved wavefront reconstruction for Shack–Hartmann wavefront sensor in the presence of shock-related distortions","authors":"Ethan D. Chu, Timothy J. Bukowski, Stanislav Gordeyev","doi":"10.1016/j.optlastec.2025.112764","DOIUrl":"10.1016/j.optlastec.2025.112764","url":null,"abstract":"<div><div>Previous research has demonstrated that large density gradients, such as those produced by supersonic shockwaves, adversely affect the wavefront reconstruction of Shack–Hartmann wavefront sensors (SHWFS). Shocks cause non-diffraction-limited irradiance patterns, leading to incorrect local tilt measurements by SHWFS, and, as a consequence, degraded reconstructed wavefront accuracy. To study the effect of shocks on the reconstruction accuracy of SHWFS, experimental wavefront measurements were performed, when the interrogating laser beam was propagated along a local shock formed in transonic flow over a partial cylinder. The resulting wavefronts were simultaneously measured by a SHWFS and a digital holography wavefront sensor (DHWFS) and then compared, treating the DHWFS as the ”ground truth.” Significant error was found in the SHWFS measurements, with the error increasing nonlinearly with shock strength. Three metrics, specifically standard deviation, kurtosis, and slope discrepancy, were evaluated for their effectiveness in identifying the dots, distorted by the local shock. Excluding points that exceeded a set threshold significantly improved wavefront accuracy. A complete SHWFS wavefront was then recovered by filling in the excluded points with a spline interpolation. This algorithm decreased the root mean squared error of the SHWFS wavefront by around 30% on average. These findings contribute to the advancement of shock-wave-tolerant phase reconstruction algorithms and introduce a method for more accurate wavefront recovery in the case where a shock partially crosses the aperture.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"187 ","pages":"Article 112764"},"PeriodicalIF":4.6,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143714799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Generation and dynamics of dual-wavelength solitons in ultrafast fiber lasers

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2025-03-26 DOI: 10.1016/j.optlastec.2025.112873

Ling Yun , Guotao Chen , Guangwei Chen , Fan Ye , Jie Zhou , Zuxing Zhang , Ruilin Zheng

{"title":"Generation and dynamics of dual-wavelength solitons in ultrafast fiber lasers","authors":"Ling Yun , Guotao Chen , Guangwei Chen , Fan Ye , Jie Zhou , Zuxing Zhang , Ruilin Zheng","doi":"10.1016/j.optlastec.2025.112873","DOIUrl":"10.1016/j.optlastec.2025.112873","url":null,"abstract":"<div><div>We present a comprehensive investigation of dual-wavelength soliton dynamics in an erbium-doped fiber laser incorporating lead selenide quantum dots (PbSe QDs) as a saturable absorber. Stable dual-wavelength operation at 1529 nm and 1557 nm is demonstrated, exhibiting distinct spectral and temporal characteristics. Reversible transitions between dual- and single-wavelength states are achieved by tuning the intracavity polarization controller. Numerical simulations, in excellent agreement with experimental results, reveal that dual-wavelength generation arises from the interplay of the erbium gain profile, birefringence-induced spectral filtering, and the nonlinear absorption of PbSe QDs. Additionally, soliton interactions exhibit elastic collisions with a 562 Hz repetition-rate difference, confirming independent propagation dynamics. These findings establish PbSe QDs as a promising nonlinear medium for multi-wavelength fiber lasers, with potential applications in dual-comb spectroscopy and wavelength-division multiplexing networks.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"187 ","pages":"Article 112873"},"PeriodicalIF":4.6,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimal process parameter combinations search for desired deposited layer geometry in laser-arc hybrid additive manufacturing based on multi-pass overlapping deposited layer contour prediction model and improved NSGA-II algorithm

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2025-03-26 DOI: 10.1016/j.optlastec.2025.112700

Junhua Wang , Luhaotian Feng , Junfei Xu , Xiaoqin Zha , Yunhao Cui , Kun Li , Tancheng Xie

{"title":"Optimal process parameter combinations search for desired deposited layer geometry in laser-arc hybrid additive manufacturing based on multi-pass overlapping deposited layer contour prediction model and improved NSGA-II algorithm","authors":"Junhua Wang , Luhaotian Feng , Junfei Xu , Xiaoqin Zha , Yunhao Cui , Kun Li , Tancheng Xie","doi":"10.1016/j.optlastec.2025.112700","DOIUrl":"10.1016/j.optlastec.2025.112700","url":null,"abstract":"<div><div>Laser-arc hybrid additive manufacturing (LHAM) leverages the synergistic effect of a combined laser-arc heat source to overcome the limitations of both laser additive manufacturing (LAM) and wire arc additive manufacturing (WAAM). As an advanced process, LHAM holds significant potential for development within the realm of metal additive manufacturing (MAM). How to achieve an optimal combination of process parameters based on the ideal deposited layer geometry of LHAM is a key issue that constrains the maturation of the LHAM process. In this study, an automated solution for obtaining the ideal deposited layer and searching for optimal process parameter combination for LHAM multi-pass overlapping was investigated. Orthogonal experiment was designed to obtain the original data of LHAM multi-pass overlapping deposited layer. Parabolic curve was used to fit the LHAM single-pass layer contour and a multi-pass overlapping layer contour prediction model was constructed based on the iterative approach. The accuracy of the prediction model was evaluated using three metrics. Aiming at the shortcomings of the second-generation non-dominated genetic algorithm (NSGA-II), an improved NSGA-II algorithm was proposed, and an optimisation model for the combination of process parameters was constructed by combining the entropy-weight TOPSIS method. The optimisation model was able to automatically optimise the process parameter combinations through the expected deposition layer morphology parameters. The relative error of the actual height of the multi-pass overlapping layer from the preset height selected by the optimal combination of process parameters was only 2.067%, and a smoother surface of the layer was obtained, which verified the feasibility of the optimisation model.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"187 ","pages":"Article 112700"},"PeriodicalIF":4.6,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Model-based tip-tilt correction for segmented mirror of space telescope using extended beacon

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2025-03-26 DOI: 10.1016/j.optlastec.2025.112852

Zexia Zhang , Bing Dong , Guoliang Tian , Jinping He

{"title":"Model-based tip-tilt correction for segmented mirror of space telescope using extended beacon","authors":"Zexia Zhang , Bing Dong , Guoliang Tian , Jinping He","doi":"10.1016/j.optlastec.2025.112852","DOIUrl":"10.1016/j.optlastec.2025.112852","url":null,"abstract":"<div><div>A model-based tip-tilt correction method using extended beacons is proposed for aligning the segmented mirror of space telescopes. This method is based on the relationship between the low spatial frequency content of images and the coefficients of Chebyshev segmented tip-tilt (CSTT) modes. Tip-tilt correction is accomplished by introducing positive CSTT modal biases with known amplitudes and capturing 2N-1 focal images in each correction cycle, where N is the number of segments. The performance of the method is evaluated through both simulations and experiments. The results demonstrate that the tip-tilt errors can be effectively corrected within only a small number of iterations, achieving an accuracy of λ/30. Additionally, the impacts of various factors on the correction performance are analyzed, including spectral bandwidth, image noise, the presence of piston errors and figure errors, and the number of mirror segments. The proposed method does not require additional optical components and offers high accuracy along with low computational complexity, making it highly suitable for cophasing of earth-observation segmented space telescopes.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"187 ","pages":"Article 112852"},"PeriodicalIF":4.6,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

In-situ surface inspection for wire-arc directed energy deposition integrating 3D topography reconstruction, defect detection and roughness measurement

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2025-03-26 DOI: 10.1016/j.optlastec.2025.112871

Hao Wang , Songyu Qi , Tiejun Zang , Chao Chen , Xiaohui Zhao , Yu Liu

{"title":"In-situ surface inspection for wire-arc directed energy deposition integrating 3D topography reconstruction, defect detection and roughness measurement","authors":"Hao Wang , Songyu Qi , Tiejun Zang , Chao Chen , Xiaohui Zhao , Yu Liu","doi":"10.1016/j.optlastec.2025.112871","DOIUrl":"10.1016/j.optlastec.2025.112871","url":null,"abstract":"<div><div>In wire-arc directed energy deposition (WA-DED), the in-situ surface inspection is imperative for acquiring 3D topographies, detecting weld bead surface defects, and measuring surface roughness to facilitate autonomous quality evaluation and repair path generation. However, existing offline inspection methods fail to provide comprehensive, real-time surface characterization. To address this limitation, a laser vision-based in-situ inspection system, where 3D topography reconstruction, defect detection and roughness measurement are innovatively integrated into a unified real-time scanning task, is developed. The inspection system consists of three subprocesses running simultaneously. By employing the novel laser centerline extraction algorithm CIICEA alongside the novel spatial curve fitting algorithm K-QCBFA, the complete 3D topographies of the printed geometries are reconstructed with a high precision of 0.247 mm. Surface hump and depression defects on the weld bead are identified and classified with a high accuracy of 97.44 % by applying the specific defect detection criterion derived from the analysis of the weld bead height difference curve. Utilizing the surface datum plane determined by the RANSAC algorithm, the geometrical indices for surface roughness, including <span><math><mrow><msub><mi>R</mi><mi>z</mi></msub></mrow></math></span>, <span><math><mrow><msub><mi>R</mi><mi>a</mi></msub></mrow></math></span>, <span><math><mrow><msub><mi>S</mi><mi>z</mi></msub></mrow></math></span> and <span><math><mrow><msub><mi>S</mi><mi>a</mi></msub></mrow></math></span>, are quantitatively evaluated with errors of ≤ 0.1558 mm. Experimental validations demonstrate that the system provides comprehensive multi-source surface information during the WA-DED process, capabilities not achievable with single-function inspection technologies, thus enabling sufficient data for effective part quality improvement.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"187 ","pages":"Article 112871"},"PeriodicalIF":4.6,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Turbulence-tolerant 12-bit/symbol OAM shift keying free space optical communication using a two-stage neural network

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2025-03-26 DOI: 10.1016/j.optlastec.2025.112758

Lin Weiqing, Liu Yejin, Lian Shengdi, Li Yanghong, Wu Zitong, Xiao Yu, Huang Haoyu, Liang Yaodong, Deng Dongmei

{"title":"Turbulence-tolerant 12-bit/symbol OAM shift keying free space optical communication using a two-stage neural network","authors":"Lin Weiqing, Liu Yejin, Lian Shengdi, Li Yanghong, Wu Zitong, Xiao Yu, Huang Haoyu, Liang Yaodong, Deng Dongmei","doi":"10.1016/j.optlastec.2025.112758","DOIUrl":"10.1016/j.optlastec.2025.112758","url":null,"abstract":"<div><div>Orbital angular momentum-shift keying free space optical (OAM-SK FSO) communication inherently suffers from disturbances in atmospheric turbulence (AT), which significantly degrades the communication performance. In this manuscript, we demonstrate a turbulence-tolerant 12 bit/symbol OAM-SK FSO communication system using a two-stage neural network, which features a modified U-Net for compensating OAM modes, and a two-step convolutional neural network for decoding. In simulation, the full capability (accuracy <span><math><mrow><mo>></mo><mn>98</mn><mo>.</mo><mn>87</mn><mtext>%</mtext></mrow></math></span>) of the proposed model in recognizing all types of OAM modes disrupted by different levels of AT is demonstrated. After transfer learning on experiment data, the model still exhibits good generalization in the practical system. The transmission of a 12,000-depth pseudo-random binary sequence encoded by 1000 12-bit symbols is displayed in a mock-up experiment, and bit error rates of <span><math><mrow><mn>2</mn><mo>.</mo><mn>50</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>4</mn></mrow></msup></mrow></math></span>, <span><math><mrow><mn>4</mn><mo>.</mo><mn>17</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>4</mn></mrow></msup></mrow></math></span>, <span><math><mrow><mn>4</mn><mo>.</mo><mn>75</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup></mrow></math></span> under weak, moderate and strong AT are observed respectively. This study provides a new, to the best of our knowledge, platform for high-capacity, robust FSO communication.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":"187 ","pages":"Article 112758"},"PeriodicalIF":4.6,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0