Impact of Sampling-Source Extinction Ratio in Linear Optical Sampling

We report on the impact of the sampling-source extinction ratio (ER) in a linear optical sampling system. To this effect, an analytical model is developed and contrasted with experimental data and numerical simulation, to determine the operational limits of the monitoring system. The ER of the reconstructed signal consists of a combined contribution from the magnitude of the symbol under test and the magnitude of the product between its neighboring symbols and the corresponding subpulses of the sampling source. The sampled signal can be completely reconstructed from its samples for ERs of the sampling source above 35 dB.