Channel Estimation Based on Interference Cancellation Method for FBMC-PON

Abstract

Based on the traditional orthogonal frequency division multiplexing passive optical network (OFDM-PON) system, filter bank multi-carrier passive optical network (FBMC-PON) eliminates the CP by introducing a prototype filter, dramatically improving spectral efficiency. Meanwhile, thanks to its excellent bit error rate (BER) performance, FBMC-PON becomes one of the significant alternatives to OFDM-PON. In previous practical cases, the interference approximation method (IAM) based channel estimation algorithm, which mainly enhances the power of train sequence, plays superior in FBMC-PON. However, the interference cancellation method (ICM) channel estimation method is a better choice due to the self-cancellation of imaginary interference, especially for short-distance optical fiber access channels. We analyze the different train sequences and consider that in the short fiber channel of PON, it is more vital to suppress the imaginary interference rather than improve the train sequence’s power. The simulation results show that the performance of FBMC-PON based on ICM is one order of magnitude higher than that of OFDM-PON and half an order of magnitude higher than that of IAM in the case of 20km fiber. Our proposed channel estimation algorithm only changes the structure of the train sequence and does not increase any additional computational complexity.