Performance comparison of power fading mitigation techniques in multiband OFDM-UWB signals transmission along LR-PONs

The single sideband (SSB) modulation is assessed as a means to mitigate the dispersion-induced power fading on the distribution of ortogonal frequency division multiplexing (OFDM) ultra wideband (UWB) radio signals along long-reach passive optical networks (LR-PONs). Particularly, two different SSB architectures, namely, Sieben's architecture and four phase modulator (FPM) architecture are optimized to provide maximum sideband suppression. The minimum optical signal-to-noise ratio (OSNR) required to simultaneously distribute all the 14 OFDM-UWB sub-bands along the LR-PON distances ranging between 80 and 100 km is also evaluated through numerical simulation. FPM architecture is preferable over Sieben's architecture because the latter SSB architecture generates carriers-carriers beat term at the photodetector output with high power, thereby causing significant degradation in the OFDM-UWB sub-bands with lower central frequencies. The simultaneous distribution of the 14 SSB OFDM-UWB sub-bands in the LR-PON using the FPM architecture shows a minimum OSNR penalty of 3 dB compared with the centralized dispersion compensation technique.