Thesis - Department of Electronic & Computer Engineering

the system level. Our results show that arbitration is the best choice for neuromorphicsystems whose activity is sparse in space and in time. A Poisson model has been usedfor collision analysis in feed-forward communication system [12]. For this pulse coupledrecurrent system, we propose a periodic model, which is shown to give bettermodelling than Poisson model, especially for a network whose size is small or whichcontains neurons with significantly different activities. These results should be applicableto the implementation of the recurrent cortical competition and other complexnetworks with pulse coupled techniques.1.3 Thesis OrganizationThe remaining of this thesis is organized as follows. In chapter 2 we introduce thecontinuous WTA models on which the pulse coupled WTA neural networks are based.Pulse based communication schemes are presented in chapter 3. Related works arealso listed and compared. In chapter 4, the system level models of the communicationschemes used in this work are described. Chapter 5 elaborates the pulse coupled modelin detail. Analysis on the behavior of the model with different design parameters arealso covered. Performances of pulse coupled winner-take-all networks under differentcommunication schemes are compared, with simulation results and discussions. Aperiodic model is proposed for collision analysis. Conclusions are summarized inchapter 6.3