Compressive Sensing system for recording of ECoG signals in-vivo

Figure 6.2.5.3. BPDN method reconstruction comparison.In Fig.6.2.5.2 and Fig.6.2.5.3 input reconstruction is shown for all the ideal cases have beentested. It is clearly observable that the best recovery for the full energy range has beenachieved by the non-inverting SC Integrator without parasitic effects (in yellow), closely followedby the SC Integrator with parasitic effects. The continuous time configurations, in passive oractive topologies have demonstrated to carry out a worst charge and discharge of the capacitorduring the integration phases, and so the final accumulated values for each of the compressedsamples in each of the paths of the channels move away from the theoretical solution calculatedin Matlab, whereupon the reconstructed signal is more noisy than in discrete time-basedintegrators. This discussion is summarized in 6.2.6 with the SNR analysis.6.2.6. SNR Calculations [32]Signal to Noise Ratio has been calculated by considering Eq. 23:(23)Where is the original input signal and is the reconstructed one. In Table 6.2.6.1 SNRcalculations for each of the ideal topologies which have been presented in 6.5 are summarizedfor both of the recovery methods have been considered, LASSO-based and BPDN-based one.According to the results obtained below, the best topology to be improved is the one presentedin 6.2.5, based on switched capacitors and enhanced not to be sensitive to the parasitic whichare introduced by C 1 . Henceforward, a mixing-integration real topology based on switchedcapacitors is considered.68