双模式涡旋光束的轨道角动量的精确识别

Accuracy Recognition of Orbital Angular Momentum of Dual-Mode Vortex Beams

基于轨道角动量(OAM)的自由空间光学通信被认为是很有前景的下一代通信应用,为了实现OAM复用通信,需要突破的关键技术之一就是接收端涡旋光束OAM的探测。采用卷积神经网络方法,提出并研究了一种双模式涡旋光束的OAM精确识别的理论方案。这种OAM光束可以提供两个可控的自由度-OAM量子数和比例参数。研究了训练样本的图片分辨率或样本数目与OAM识别准确率的关系。还研究了不同的OAM量子数l、比例参数n与OAM识别准确率的关系。研究表明,当OAM量子数的范围为1~10,比例参数为0.01~0.99时,不同OAM模式的识别准确率达到100%。

Free space optical communication based on orbital angular momentum(OAM)is considered to be a promising next generation communication application.In order to realize OAM multiplexing communication,one of the key technologies is the detection of vortex beam’s OAM at the receiving end.Using convolution neural network method,a theoretical scheme for accurate identification of OAM of dual-mode vortex beams is studied.The OAM beam can provide two controllable degrees of freedom,e.g.the topological charge number l and the proportional coefficient n.The relationship of the training sample resolution or the number associated with the accuracy of the model is presented.The recognition accuracy is closely related with the quantum number l of the OAM,and the proportional coefficient n.This studies show that when l ranges from 1 to 10,and n varies from 0.01 to 0.99,the recognition accuracy rate of OAM is 100%.