Signal remodulation mechanism is a promising cost-effective choice for future optical access networks. This paper investigates the scheme of the phase modulator to remodulate upstream data in the bidirectional WDM PON and TWDM PON system. The simulation results of downstream is carried out using two data formats such as RZ and NRZ at varying lengths of single mode fibers in this scheme. In addition, the upstream transmission compares different remodulators such as Phase modulator, Mach–Zehnder modulator (MZM) and Electroabsorption modulator. By analyzing the eye diagram and Q-value, the performance of upstream and downstream transmission is obtained. It is observed that the PM remodulation TWDM-PON with NRZ modulation format has better performance, which is a rational solution for NG-PON2 cost-effectiveness.