{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T21:45:27Z","timestamp":1769118327139,"version":"3.49.0"},"reference-count":40,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2017,10,30]],"date-time":"2017-10-30T00:00:00Z","timestamp":1509321600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["No. 51327005, No.91420203, No.61605008"],"award-info":[{"award-number":["No. 51327005, No.91420203, No.61605008"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Jiangsu Province Natural Science Foundation of China","award":["No. BK20160375"],"award-info":[{"award-number":["No. BK20160375"]}]},{"name":"National Major Scientific Instruments and Equipment Development Project","award":["2014YQ350461"],"award-info":[{"award-number":["2014YQ350461"]}]},{"name":"Singapore Defense Innovative Research Program","award":["No. MINDEF-NUS-DIRP\/2012\/02"],"award-info":[{"award-number":["No. MINDEF-NUS-DIRP\/2012\/02"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>A novel de-noising method for improving the performance of full-waveform light detection and ranging (LiDAR) based on differential optical path is proposed, and the mathematical models of this method are developed and verified. Backscattered full-waveform signal (BFWS) is detected by two avalanche photodiodes placed before and after the focus of the focusing lens. On the basis of the proposed method, some simulations are carried out and conclusions are achieved. (1) Background noise can be suppressed effectively and peak points of the BFWS are transformed into negative-going zero-crossing points as stop timing moments. (2) The relative increment percentage of the signal-to-noise ratio based on the proposed method first dramatically increases with the increase of the distance, and then the improvement gets smaller by increasing the distance. (3) The differential Gaussian fitting with the Levenberg-Marquardt algorithm is applied, and the results show that it can decompose the BFWS with high accuracy. (4) The differential distance should not be larger than c\/2 \u00d7 \u03c4rmin, and two variable gain amplifiers can eliminate the inconsistency of two differential beams. The results are beneficial for designing a better performance full-waveform LiDAR.<\/jats:p>","DOI":"10.3390\/rs9111109","type":"journal-article","created":{"date-parts":[[2017,10,30]],"date-time":"2017-10-30T12:16:23Z","timestamp":1509365783000},"page":"1109","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["A Novel De-Noising Method for Improving the Performance of Full-Waveform LiDAR Using Differential Optical Path"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1702-7122","authenticated-orcid":false,"given":"Yang","family":"Cheng","sequence":"first","affiliation":[{"name":"Key Laboratory of Biomimetic Robots and Systems, Ministry of Education, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Department of Biomedical Engineering, National University of Singapore, Singapore 117575, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jie","family":"Cao","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biomimetic Robots and Systems, Ministry of Education, Beijing Institute of Technology, Beijing 100081, China"},{"name":"NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou 215123, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qun","family":"Hao","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biomimetic Robots and Systems, Ministry of Education, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuqing","family":"Xiao","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biomimetic Robots and Systems, Ministry of Education, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fanghua","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biomimetic Robots and Systems, Ministry of Education, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenze","family":"Xia","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biomimetic Robots and Systems, Ministry of Education, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Department of Biomedical Engineering, National University of Singapore, Singapore 117575, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kaiyu","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Biomimetic Robots and Systems, Ministry of Education, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haoyong","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, National University of Singapore, Singapore 117575, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,10,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4771","DOI":"10.1364\/OE.24.004771","article-title":"Deriving backscatter reflective factors from 32-channel full-waveform LiDAR data for the estimation of leaf biochemical contents","volume":"24","author":"Li","year":"2016","journal-title":"Opt. Express"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"537","DOI":"10.3319\/TAO.2016.01.29.04(ISRS)","article-title":"Mapping CHM and LAI for Heterogeneous Forests Using Airborne Full-Waveform LiDAR Data","volume":"27","author":"Tseng","year":"2016","journal-title":"Terr. Atmos. Ocean. Sci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1016\/j.isprsjprs.2005.12.001","article-title":"Gaussian decomposition and calibration of a novel small-footprint full-waveform digitising airborne laser scanner","volume":"60","author":"Wagner","year":"2006","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"5133","DOI":"10.3390\/rs70505133","article-title":"Performance assessment of high resolution airborne full waveform LiDAR for shallow river bathymetry","volume":"7","author":"Pan","year":"2015","journal-title":"Remote Sens."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1433","DOI":"10.1080\/01431160701736398","article-title":"3D vegetation mapping using small-footprint full-waveform airborne laser scanners","volume":"29","author":"Wagner","year":"2008","journal-title":"Int. J. Remote Sens."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"229","DOI":"10.3390\/rs70100229","article-title":"Modeling forest aboveground biomass and volume using airborne LiDAR metrics and forest inventory and analysis data in the Pacific Northwest","volume":"7","author":"Sheridan","year":"2014","journal-title":"Remote Sens."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"9951","DOI":"10.3390\/rs6109951","article-title":"Now you see it\u2026now you don\u2019t: Understanding airborne mapping LiDAR collection and data product generation for archaeological research in Mesoamerica","volume":"6","author":"Carter","year":"2014","journal-title":"Remote Sens."},{"key":"ref_8","first-page":"447","article-title":"Land Cover Classification from Full-Waveform LIDAR Data Based on Support Vector Machines","volume":"XLI-B3","author":"Zhou","year":"2016","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1016\/j.optlaseng.2016.09.001","article-title":"Target recognition of log-polar ladar range images using moment invariants","volume":"88","author":"Xia","year":"2017","journal-title":"Opt. Lasers Eng."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"S71","DOI":"10.1016\/j.isprsjprs.2011.09.008","article-title":"Relevance assessment of full-waveform LiDAR data for urban area classification","volume":"66","author":"Mallet","year":"2011","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"169","DOI":"10.3319\/TAO.2014.12.02.02(EOSI)","article-title":"Land Cover Classification Accuracy Assessment Using Full-Waveform LiDAR Data","volume":"26","author":"Chang","year":"2015","journal-title":"Terr. Atmos. Ocean. Sci."},{"key":"ref_12","first-page":"87","article-title":"Classifying land cover based on calibrated full-waveform airborne light detection and ranging data","volume":"11","author":"Xu","year":"2013","journal-title":"Chin. Opt. Lett."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"100","DOI":"10.3832\/ifor0562-004","article-title":"Analysis of full-waveform LiDAR data for forestry applications: A review of investigations and methods","volume":"4","author":"Pirotti","year":"2011","journal-title":"iForest Biogeosci. For."},{"key":"ref_14","unstructured":"Ducic, V., Hollaus, M., Ullrich, A., Wagner, W., and Melzer, T. (2006, January 14\u201315). 3D vegetation mapping and classification using full-waveform laser scanning. Proceedings of the International Workshopd Remote Sensing in Forestry, Vienna, Austria."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1407","DOI":"10.1080\/01431160701736448","article-title":"Analysis of full waveform LIDAR data for the classification of deciduous and coniferous trees","volume":"29","author":"Reitberger","year":"2008","journal-title":"Int. J. Remote Sens."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.isprsjprs.2008.09.007","article-title":"Full-waveform topographic LiDAR: State-of-the-art","volume":"64","author":"Mallet","year":"2009","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2014","DOI":"10.3390\/rs5042014","article-title":"Characterization of Canopy Layering in Forested Ecosystems Using Full Waveform LiDAR","volume":"5","author":"Whitehurst","year":"2013","journal-title":"Remote Sens."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Li, D., Xu, L., Li, X., and Wu, D. (2014, January 14\u201317). A novel full-waveform LiDAR echo decomposition method and simulation verification. Proceedings of the IEEE International Conference on Imaging Systems and Techniques, Santorini, Greece.","DOI":"10.1109\/IST.2014.6958470"},{"key":"ref_19","first-page":"1989","article-title":"Modified Levenberg\u2013Marquardt-Based Optimization Method for LiDAR Waveform Decomposition","volume":"38","author":"Xu","year":"2000","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"563","DOI":"10.1364\/OE.22.000563","article-title":"Differential optical-path approach to improve signal-to-noise ratio of pulsed-laser range finding","volume":"22","author":"Hao","year":"2014","journal-title":"Opt. Express"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2360","DOI":"10.1364\/AO.43.002360","article-title":"Design and performance of a multiwavelength airborne polarimetric LiDAR for vegetation remote sensing","volume":"43","author":"Tan","year":"2004","journal-title":"Appl. Opt."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"25935","DOI":"10.1364\/OE.20.025935","article-title":"Range determination for generating point clouds from airborne small footprint LiDAR waveforms","volume":"20","author":"Qin","year":"2012","journal-title":"Opt. Express"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"779","DOI":"10.1016\/j.optlaseng.2005.07.010","article-title":"Simple approach to predict APD\/PMT LiDAR detector performance under sky background using dimensionless parametrization","volume":"44","author":"Agishev","year":"2006","journal-title":"Opt. Lasers Eng."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Lai, X., and Zheng, M. (2015). A Method for LiDAR Full-Waveform Data. Math. Probl. Eng., 2015.","DOI":"10.1155\/2015\/164318"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"3242","DOI":"10.1109\/TGRS.2011.2178420","article-title":"A Robust Signal Preprocessing Chain for Small-Footprint Waveform LiDAR","volume":"50","author":"Wu","year":"2012","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Zhang, Y., Ma, X., Hua, D., Cui, Y., and Sui, L. (2010, January 16\u201318). An EMD-based method for LiDAR signal. Proceedings of the 2010 3rd International Congress on Image and Signal Processing, Yantai, China.","DOI":"10.1109\/CISP.2010.5648129"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Azadbakht, M., Fraser, C.S., Zhang, C., and Leach, J. (2013, January 11\u201313). A signal denoising method for full-waveform LiDAR data. Proceedings of the ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences, Antalya, Turkey.","DOI":"10.5194\/isprsannals-II-5-W2-31-2013"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1016\/j.optcom.2004.01.017","article-title":"Noise reduction in LiDAR signal based on discrete wavelet transform","volume":"233","author":"Fang","year":"2004","journal-title":"Opt. Commun."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Persson, \u00c5., S\u00f6derman, U., T\u00f6pel, J., and Ahlberg, S. (2005, January 12\u201314). Visualization and analysis of full-waveform airborne laser scanner data. Proceedings of the International Archives of Photogrammetry Remote Sensing and Spatial Information Sciences, Workshop Laser scanning, Enschede, The Netherlands.","DOI":"10.1117\/12.604655"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1228","DOI":"10.1109\/4.938373","article-title":"A wide dynamic range receiver channel for a pulsed time-of-flight laser radar","volume":"36","author":"Ruotsalainen","year":"2001","journal-title":"IEEE. J. Solid-State Circuits"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"25026","DOI":"10.1364\/OE.24.025026","article-title":"Analytical and numerical approaches to study echo laser pulse profile affected by target and atmospheric turbulence","volume":"24","author":"Hao","year":"2016","journal-title":"Opt. Express"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Xu, G., Pang, Y., and Li, Z. (2011). Calibration of full-waveform LiDAR data by range between sensor and target and its impact for landscape classification. Int. Soc. Optics Photonics, 8286.","DOI":"10.1117\/12.912741"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1007\/s00340-013-5447-9","article-title":"A method of background noise reduction in LiDAR data","volume":"113","author":"Cao","year":"2013","journal-title":"Appl. Phys. B"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Mitev, V., Matthey, R., Carmo, J.P.D., and Ulbrich, G. (2005, January 19\u201320). Signal-to-noise ratio of pseudo-random noise continuous wave backscatter LiDAR with analog detection. Proceedings of the SPIE 5984, LiDAR Technologies, Techniques, and Measurements for Atmospheric Remote Sensing, Bruges, Belgium.","DOI":"10.1117\/12.627638"},{"key":"ref_35","first-page":"89801","article-title":"Errata: Review of ladar: A historic, yet emerging, sensor technology with rich phenomenology","volume":"51","author":"McManamon","year":"2012","journal-title":"Opt. Eng."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"4437","DOI":"10.1364\/AO.45.004437","article-title":"Estimating random errors due to shot noise in backscatter LiDAR observations","volume":"45","author":"Liu","year":"2006","journal-title":"Appl. Opt."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"549","DOI":"10.3319\/TAO.2016.02.19.01(ISRS)","article-title":"Full-Waveform LiDAR Point Cloud Land Cover Classification with Volumetric Texture Measures","volume":"27","author":"Tsai","year":"2016","journal-title":"Terr. Atmos. Ocean. Sci."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"13761","DOI":"10.1364\/OE.23.013761","article-title":"Synergistic application of geometric and radiometric features of LiDAR data for urban land cover mapping","volume":"23","author":"Qin","year":"2015","journal-title":"Opt. Express"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1190","DOI":"10.1109\/LGRS.2013.2288152","article-title":"Robust Ground Peak Extraction with Range Error Estimation Using Full-Waveform LiDAR","volume":"11","author":"Jalobeanu","year":"2014","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1303","DOI":"10.1080\/01431160903380599","article-title":"Rigorous pulse detection from full-waveform airborne laser scanning data","volume":"31","author":"Lin","year":"2010","journal-title":"Int. J. Remote Sens."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/11\/1109\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:48:55Z","timestamp":1760208535000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/11\/1109"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,10,30]]},"references-count":40,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2017,11]]}},"alternative-id":["rs9111109"],"URL":"https:\/\/doi.org\/10.3390\/rs9111109","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,10,30]]}}}