Fig. 4
(a) An example of a serialised information signal, \(\:j\left(t\right)\), obtained for a single instance of transmittance measurement of ethanol \(\:\mathcal{T}=[T\left({\lambda\:}_{c,1}\right),\:T\left({\lambda\:}_{c,2}\right),T({\lambda\:}_{c,3}\left)\right]\). The signal is periodic with \(\:3\tau\:\), where \(\:\tau\:\) is the round-trip time for the EORC. (b) A depiction of a mask signal, \(\:m\left(t\right)\), with 30% modulation depth and a bias of 1. The mask signal is periodic with \(\:\tau\:\) and each mask lasts for \(\:\theta\:=\:\tau\:/{N}_{x}\), where \(\:{N}_{x}\) is the number of random value masks (5 in this example). (c) An example of the EORC input signal, \(\:u\left(t\right)\), created from the modulation of the serialised information signal, \(\:j\left(t\right)\), by the mask signal, \(\:m\left(t\right)\). The depicted example is for a single instance of an ethanol transmittance measurement with 5 mask values, shown in different colours. (d) A visualisation of demultiplexing for an input signal, \(\:u\left(t\right)\), with \(\:{N}_{x}=5\). Application of demultiplexing to the reservoir activation states, \(\:x\left(t\right)\), instead, yields the neuron activation states (\(\:\mathbf{X}\)).
