Equalizer in Optical OFDM using Optisystem

I am working on Optical OFDM using Optisystem. Detection used is Coherent.
I used 4QAM modulator and demodulator.
It is basically four channel OFDM each having data rate of 10 Gb/s.
These four channels are send simultaneously using WDM.
The Transmission link consists of two optical amplifiers and two optical fibers.
After coherent detection i got bit error rate in the range of 10 raise to power -9.
I also check BER with LPF after coherent detection.
Now i am trying to use Equalizer.
I am refering a paper which user Tunable Adaptive Equalizer having Phase modulator and Dispersive element.
Please Help me I do not Know how to get this equalizer.
I have tried MLSE equalizer but it results in more BER.

The CW laser power is -5 dbm and linewidth is 0.15 Mhz.
LO power is -2 dbm and linewidth 0.15 Mhz.

I am attaching the block diagram image.

can you plz help me with first part of your project..that is simulation of CO-OFDM without eqaulizer..
I need urgent help with it...at least give me complete block diagram and values in optisystem

ok ,where the problem exactly ,I did that befor one year , can you send picture or file ,I will did for u because the setting for parameters very important ,especielly BER analyser.