Processing-Speed Enhancement for a Long-Loop VCSEL-Based Time-Delay Reservoir Computing

Clock acceleration is proposed to enhance the processing speed for a long-loop VCSEL-based time-delay reservoir computing (TDRC). The polarization manipulation is further investigated to solve the speed degradation problem due to unwanted resonances at critical time ratios between the input clock cycle and the feedback delay. Then, complex time series prediction task is adopted to test the feasibility of proposed method. Numerical results indicate that the processing speed can be doubled by clock acceleration without significant performance degradation. Moreover, the use of orthogonal polarization optical feedback effectively mitigates the problems due to critical time ratios, increases the prediction performance by about 50%, and thereby improving the tunability of processing speed.