Encoding and decoding communications based on superimposed-state double-ring perfect vortex beam arrays

An encoding/decoding scheme utilzing superimposed-state double-ring perfect vortex beam arrays (SDR-PVBAs) is proposed. SDR-PVBAs are generated based on the displacement theorem of the Fourier transform. The double rings within the array exhibit a 256 distinct morphologies, encoded as hexadecimal values from 00 to FF, corresponding to the gray levels ranging from 0 to 255. Consequently, SDR-PVBAs composed of multiple double rings can transmit coded information, enabling high-capacity communication. At the receiver end, a residual network (ResNet) is employed to recognize the various superposition modes and decode the information carried by the arrays. In the experiment, a 180 × 180 pixel grayscale image was successfully transmitted. After decoding of the arrays using ResNet, the image was accurately recovered with a recognition accuracy of 99.926%, validating the feasibility of the proposed scheme. This research extends the application of PVBAs in high-capacity optical communications.