{"title":"利用光束测量估算湍流介质的时变折射率:一种数据同化方法。","authors":"Anjali Nair, Qin Li, Samuel N Stechmann","doi":"10.1364/JOSAA.518013","DOIUrl":null,"url":null,"abstract":"<p><p>In applications such as free-space optical communication, a signal is often recovered after propagation through a turbulent medium. In this setting, it is common to assume that limited information is known about the turbulent medium, such as a space- and time-averaged statistic (e.g., root-mean-square), but without information about the state of the spatial variations. It could be helpful to gain more information if the state of the turbulent medium can be characterized with the spatial variations and evolution in time described. Here, we propose to investigate the use of data assimilation techniques for this purpose. A computational setting is used with the paraxial wave equation, and the extended Kalman filter is used to conduct data assimilation using intensity measurements. To reduce computational cost, the evolution of the turbulent medium is modeled as a stochastic process. Following some past studies, the process has only a small number of Fourier wavelengths for spatial variations. The results show that the spatial and temporal variations of the medium are recovered accurately in many cases. In some time windows in some cases, the error is large for the recovery. Finally, we discuss the potential use of the spatial variation information for aiding the recovery of the transmitted signal or beam source.</p>","PeriodicalId":17382,"journal":{"name":"Journal of The Optical Society of America A-optics Image Science and Vision","volume":null,"pages":null},"PeriodicalIF":1.4000,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Estimating the time-evolving refractivity of a turbulent medium using optical beam measurements: a data assimilation approach.\",\"authors\":\"Anjali Nair, Qin Li, Samuel N Stechmann\",\"doi\":\"10.1364/JOSAA.518013\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>In applications such as free-space optical communication, a signal is often recovered after propagation through a turbulent medium. In this setting, it is common to assume that limited information is known about the turbulent medium, such as a space- and time-averaged statistic (e.g., root-mean-square), but without information about the state of the spatial variations. It could be helpful to gain more information if the state of the turbulent medium can be characterized with the spatial variations and evolution in time described. Here, we propose to investigate the use of data assimilation techniques for this purpose. A computational setting is used with the paraxial wave equation, and the extended Kalman filter is used to conduct data assimilation using intensity measurements. To reduce computational cost, the evolution of the turbulent medium is modeled as a stochastic process. Following some past studies, the process has only a small number of Fourier wavelengths for spatial variations. The results show that the spatial and temporal variations of the medium are recovered accurately in many cases. In some time windows in some cases, the error is large for the recovery. Finally, we discuss the potential use of the spatial variation information for aiding the recovery of the transmitted signal or beam source.</p>\",\"PeriodicalId\":17382,\"journal\":{\"name\":\"Journal of The Optical Society of America A-optics Image Science and Vision\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.4000,\"publicationDate\":\"2024-06-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of The Optical Society of America A-optics Image Science and Vision\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://doi.org/10.1364/JOSAA.518013\",\"RegionNum\":3,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"OPTICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of The Optical Society of America A-optics Image Science and Vision","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1364/JOSAA.518013","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"OPTICS","Score":null,"Total":0}
Estimating the time-evolving refractivity of a turbulent medium using optical beam measurements: a data assimilation approach.
In applications such as free-space optical communication, a signal is often recovered after propagation through a turbulent medium. In this setting, it is common to assume that limited information is known about the turbulent medium, such as a space- and time-averaged statistic (e.g., root-mean-square), but without information about the state of the spatial variations. It could be helpful to gain more information if the state of the turbulent medium can be characterized with the spatial variations and evolution in time described. Here, we propose to investigate the use of data assimilation techniques for this purpose. A computational setting is used with the paraxial wave equation, and the extended Kalman filter is used to conduct data assimilation using intensity measurements. To reduce computational cost, the evolution of the turbulent medium is modeled as a stochastic process. Following some past studies, the process has only a small number of Fourier wavelengths for spatial variations. The results show that the spatial and temporal variations of the medium are recovered accurately in many cases. In some time windows in some cases, the error is large for the recovery. Finally, we discuss the potential use of the spatial variation information for aiding the recovery of the transmitted signal or beam source.
期刊介绍:
The Journal of the Optical Society of America A (JOSA A) is devoted to developments in any field of classical optics, image science, and vision. JOSA A includes original peer-reviewed papers on such topics as:
* Atmospheric optics
* Clinical vision
* Coherence and Statistical Optics
* Color
* Diffraction and gratings
* Image processing
* Machine vision
* Physiological optics
* Polarization
* Scattering
* Signal processing
* Thin films
* Visual optics
Also: j opt soc am a.