A novel WDM-PON structure based on orthogonal FSK/ASK re-modulation scheme is presented in this paper.In the downstream direction

a FSK modulation technology based on phase-to-intensity modulation conversion is adopted to generate 40 Gbit/s FSK signals

while in the upstream direction

10 Gbit/s ASK signals are directly modulated onto the FSK signals to achieve orthogonal modulation format.The performances of the entire system are studied and simulation results show that this structure can satisfy the requirements for access network transmission and provides an option for the future high-rate access networks.