Abstract This study demonstrates the line coding performance integrated with measured multimode index fibers and high speed spatial single mode laser sources. The line coding that are used are pulse amplitude modulation and non return to zero coding. Optimum lighted power form with the spectral base band form wavelength based on NRZ line coding is clarified. Optimum lighted form band power with the spectral base band form wavelength based on the PAM line coding is studied. The max lighted base power base band form variations with the time durations in the presence of NRZ line coding is simulated. Optimum lighted band form power with the time durations based on both PAM and NRZ line coding. Max electrical base band power form amplitude variations with time durations based on the NRZ line coding is clarified.