Experimental performance analysis of a low complexity 20 Gb/s PAM4-PON based on legacy 10G hardware

This paper presents the experimental performance analysis of a $20 \mathrm{~Gb} / \mathrm{s}$ PAM4-PON which was deployed using 10 G legacy electrical and optical hardware. It studied the behavior of the BER vs the decrement of the received optical power on the ONU side and the behavior of the optical path penalty. The test results of the $20 \mathrm{~Gb} / \mathrm{s}$ PON were contrasted with the performance of a traditional $10 \mathrm{~Gb} / \mathrm{s}$ PAM2-NRZ PON. With a received optical power of -10 dBm it was possible to achieve a BER of $10^{-9}$ with the PAM4-PON, whilst in a PAM2-NRZ PON the same BER is achievable when a signal of $\mathbf{- 1 9} \mathrm{dBm}$ is received in the ONU. The optical path penalty of the PAM4 is greater than 2.5 dB when the optical link length is close to 30 km, but it is very low when the ODN is shorter than 25 km.