Receiver sensitivity improvement by impulsive coding

Abstract
We show that optical receivers operated impulsively are more sensitive than for nonreturn-to-zero (NRZ) operation. Impulsive sensitivity improvements of 5.8 and 4.7 dB are measured for two pin-FET receivers using a modelocked laser transmitter, and compared to theoretical expressions for the NRZ and impulsive Q-factors. We also show that the optimum detection bandwidth for impulsive coding is larger than for NRZ, in contrast to previous models.