Fig. 1. Experimental setup for IM-DD NRZ transmission system and eyediagrams

Fig. 2. Flow chart for offline DSP

Fig. 3. Flow chart for synchronization of two-way PRBS

Fig. 4. Parameter curve for transceiver S21

Fig. 5. Estimation for channel impulse response. (a) BtB; (b) over 25 km SSMF

Fig. 6. MLSE BER curves for BtB and 25 km transmission. (a) Fixed channel coefficients; (b) adaptive channel estimation

Fig. 7. BER curves for BtB. (a) FFE; (b) DFE

Fig. 8. BER curves for 25 km transmission. (a) FFE; (b) DFE

Fig. 9. Eyediagrams of received signal and equalized signal. (a) BtB, -20 dBm; (b) 25 km, -22 dBm