光电神经网络的光轴。
Optical Axons for Electro-Optical Neural Networks.
机构信息
Faculty of Automatic Control and Computer Engineering at Gheorghe Asachi Technical University of Iasi, 700050 Iasi, Romania.
Optical Communications Research Group, Faculty of Engineering and Environment at Northumbria University, Newcastle Upon Tyne NE7 7XA, UK.
出版信息
Sensors (Basel). 2020 Oct 27;20(21):6119. doi: 10.3390/s20216119.
Recently, neuromorphic sensors, which convert analogue signals to spiking frequencies, have been reported for neurorobotics. In bio-inspired systems these sensors are connected to the main neural unit to perform post-processing of the sensor data. The performance of spiking neural networks has been improved using optical synapses, which offer parallel communications between the distanced neural areas but are sensitive to the intensity variations of the optical signal. For systems with several neuromorphic sensors, which are connected optically to the main unit, the use of optical synapses is not an advantage. To address this, in this paper we propose and experimentally verify optical axons with synapses activated optically using digital signals. The synaptic weights are encoded by the energy of the stimuli, which are then optically transmitted independently. We show that the optical intensity fluctuations and link's misalignment result in delay in activation of the synapses. For the proposed optical axon, we have demonstrated line of sight transmission over a maximum link length of 190 cm with a delay of 8 μs. Furthermore, we show the axon delay as a function of the illuminance using a fitted model for which the root mean square error (RMS) similarity is 0.95.
最近,已经有研究报道了神经形态传感器,它可以将模拟信号转换为尖峰频率,用于神经机器人技术。在仿生系统中,这些传感器与主要的神经单元相连,以对传感器数据进行后处理。使用光突触可以提高尖峰神经网络的性能,光突触提供了远距离神经区域之间的并行通信,但对光信号的强度变化很敏感。对于具有多个神经形态传感器的系统,这些传感器通过光学方式与主要单元相连,使用光突触并不是优势。为了解决这个问题,本文提出并实验验证了使用数字信号光激活的带有突触的光轴。突触权重由刺激的能量编码,然后独立地进行光传输。我们表明,光强度波动和链路的不对准会导致突触的激活延迟。对于所提出的光轴,我们已经证明了在最大链路长度为 190 厘米的情况下可以进行视线传输,延迟为 8 μs。此外,我们还展示了轴突延迟作为照度的函数,使用拟合模型的均方根误差(RMS)相似性为 0.95。