112G Electrical System Performance Study based on an improved Salz SNR Methodology

In early system design stage for 112G when no silicon nor hardware components are available, an improved Salz SNR analytical model is derived and a methodology for assessing system margin is introduced. Unlike traditional ICR based Salz method, major noise terms that are recognized to be dominant and are weighted much higher in PAM4 than in NRZ systems are included. Performance ‘upper limits’ such as maximal tolerable insertion loss and crosstalk for ‘optimal’ modulation scheme is analyzed based on six backplane link architectures and those with higher possibility to meet the ‘upper limits’ are selected based on full channel modeling for margin analysis.