Suppression of Nonlinear Optical Effects in DWDM-PON by Frequency Modulation Non-Coherent Detection

We propose a simple and cost-effective method, using direct frequency modulation (FM) noncoherent detection (NCD) scheme, to suppress the nonlinear optical effects in dense wavelength division multiplexed (DWDM) communication. The FM transmitter comprises directly modulated distributed feedback laser saturable semiconductor amplifier. In NCD receiver, an slope filter as intensity (IM) signal convertor is placed before conventional photodetector. Because has more evenly power, bit-pattern-dependent are consequently suppressed. After analyzing FM-NCD system traditional IM (IM-DD) system, we found that minimum achievable BER of proposed scheme 40 dB smaller. Moreover, 2 Tbps (10 Gb/s × 200 channels) capacity was achieved by 100 km DWDM passive networks (PONs), which twice IM-DD under same condition. These results indicate WDM-PONs with strong candidates for future broad access show great potential combination metro generations PONs.