The transmission of symmetric 40 Gb/s TWDM-based NG-PON2 utilizing delay interferometer (DI) for RSOA bandwidth enhancement

• TWDM-PON is a new research trend with active research involvements from both industrial and academia worlds.
• Ultimately, TWDM-PON aims for the implementation of high bandwidth in a cost effective manner.
• We demonstrate a 40 Gb/s symmetric TWDM PON system based a low cost RSOA that is enhanced by using delay interferometer (DI) to overcome the bandwidth limitation issue in the former.
• The results have shown good performances and a successful RSOA bandwidth enhancement on TWDM-PON system.

Time and wavelength-division multiplexed passive optical network (TWDM-PON) has been finally selected as the pragmatic solution for the next-generation passive optical network stage 2 (NG-PON2). In this paper, we propose a symmetric 40 Gb/s TWDM-PON system with low cost reflective semiconductor optical amplifier (RSOA) for both downstream and upstream directions. A single bi-pass delay interferometer (DI), deployed in the optical line terminal (OLT), is used to enhance the poor performance of the RSOA with respect to the low bandwidth induced by laser chirp. With the help of the 40 GHz free spectrum range (FSR) DI, we show a successful transmission of the proposed work through simulation study where an aggregate capacity of 40 Gb/s is transported over 40 km transmission distance with 32 splits. The TWDM-PON system at BER of 10−6 has shown a minimum receiver sensitivity of −22.78 dBm and −22.71 dBm for both downstream and upstream, respectively with maximum power penalty of 2 dB for downstream channel and 2.39 dB for upstream channel.