【摘 要】
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Vortex optical communication has been a hot research field in recent years.A key step is mode recognition in the orbital angular momentum[OAM]free-space optical[FSO]communication system.In this article,we propose an OAM mode rec-ognition method based on i
【机 构】
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Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices,Guangzhou 51000
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Vortex optical communication has been a hot research field in recent years.A key step is mode recognition in the orbital angular momentum[OAM]free-space optical[FSO]communication system.In this article,we propose an OAM mode rec-ognition method based on image recognition technology,which uses the interferogram between the vortex beam and the Gaussian beam to identify the OAM mode.In order to resist the influence of atmospheric turbulence on the recognition accuracy,we added a Gaussian smoothing filter into the recognition process.Mloreover,we used random phase screens to generate interferogram sets at distances of 1 km and 2 km.The verification result shows that the proposed scheme pro-duces high identification accuracy for the distorted optical field.The average accuracy can reach 100％ and 87.78％ under the conditions of medium-and strong-turbulence levels,respectively.It is anticipated that these results might be helpful for improving the reliability of the OAM-FSO communication system in the future.
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