Role of delay-times in delay-based photonic reservoir computing

Delay-based reservoir computing has gained a lot of attention due to the relative simplicity with which this concept can be implemented in hardware. However, unnecessary constraints are commonly placed on the relationship between the delay-time and the input clock-cycle, which can have a detrimental effect on the performance. We review the existing literature on this subject and introduce the concept of delay-based reservoir computing in a manner that demonstrates that no predefined relationship between the delay-time and the input clock-cycle is required for this computing concept to work. Choosing the delay-times independent of the input clock-cycle, one gains an important degree of freedom. Consequently, we discuss ways to improve the computing performance of a reservoir formed by delay-coupled oscillators and show the impact of delay-time tuning in such systems. (c) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

Delay-based reservoir computing has attracted attention in hardware implementation due to its relative simplicity. This review paper introduces the concept of delay-based reservoir computing without requiring a predetermined relationship between delay time and input clock cycle. By independently choosing delay times, an important degree of freedom is gained. The study discusses ways to enhance computing performance in reservoirs formed by delay-coupled oscillators and demonstrates the impact of delay time tuning.