Abstract.A low cost WDM-OFDM-PON system with clipping pre-distortion and RSOA for colorless ONU is proposed. On the basis of theoretical research, the transmission performance of the back-to-back and after 25km transmission is simulated and analyzed. The results show that proposed system can guarantee the transmission performance with colorless ONUs and recover the signal after 25km transmission.

Abstract-To meet the demands of different high bandwidth service, optical orthogonal frequency-division multiple accessbased passive optical network (OFDM-PON) has been considered as one of the candidate for NG-PON2. In this paper, a joint peakto-average power ration (PAPR) reduction scheme in OFDM-PON system is proposed. The simulation results show that the system PAPR is greatly improved comparing with other methods. The required OSNR of the improved system decreases under the same BER, and the system performance is greatly improved.Keywords-peak-to-average power ration (PAPR); passive optical network (PON); orthogonal frequency division multiplexing (OFDM); daptive predistortion

Abstract-To meet the demands of different high bandwidth service, OFDM-PON has been considered as one of the candidates for NG-PON2. In this paper, downstream transmission performance based on LDPC-OFDM coding PON system is studied. The simulation results show that employing the LDPC-OFDM coding in PON system can achieve 10 Gb/s downstream transmission. The transmission performance of the LDPC-OFDM system is improved 4.2 dB than uncoded system at the BER of 10 -4 . When the SNR is greater than 2. 6 dB, the Gallager method has better BER performance than the Mackay and BIBD construction schemes, and when the SNR is greater than 4. 6 dB, LLR-BP and the improved decoding algorithm enables to improve system performance. Keywords-low-density parity-check (LDPC); passive optical network (PON); orthogonal frequency division multiplexing (OFDM)

Wavelength division multiplexing passive optical network (WDM-PON) is an important alternative technique for 5G mobile fronthaul due to the large bandwidth and low latency. Wavelength and bandwidth allocation algorithm is very important in WDM-PON. In this paper, a dynamic wavelength and bandwidth allocation algorithm considering the average traffic difference of the cells in mobile fronthaul is proposed. The algorithm allocates bandwidth with cell average traffic (CAT) under wavelength sharing scheme in WDM-PON based mobile fronthaul. The latency performance of the original static sequence allocation algorithm (SSA) and CAT based dynamic allocation algorithm is compared and analyzed. Simulation results show that the new algorithm can effectively guarantee the QoS of various types of cells in mobile fronthaul.