Effect of optical beat interference on the dynamic range of a subcarrier multiple access passive optical network using Fabry-Perot lasers

Fiber-in-the loop systems that use subcarrier multiple access can have error floors from optical beat interference (OBI). We show that, when Fabry-Perot lasers are used, OBI can limit the allowable variation in received power from the lasers in the multiple access system. We demonstrate a 7 dB increase in the allowable power variation by using a very large optical modulation index.