Performance evaluation of RZ signaling in indoor unguided optical links operating beyond 50 Mbps

We examine the performance of simple modulation techniques, such as the basic baseband pulse amplitude modulation (PAM), in indoor unguided optical links, in order to minimize both intersymbol interference (ISI), induced by multipath propagation, and phase distortion effects, due to the interference suppression receiver filter. This study has been realized by means of a direct application of the correlation operator, according to the idea of minimum-distance receiver design. We conclude that on-off keying (OOK) with return-to-zero (RZ) pulses provides better performances than other signaling formats more frequently proposed in reported works, also considered in this study. The above conclusion is validated by the corresponding bit-error rate (BER) computation