Communication stops if distance between two nodes increases

Hi,

Firstly thanks for the reply.my another question is that we are using cy8cplc20 microcontroller for powerline line communication between  two  nodes.so when the two nodes are little nearby the communication is good but when the distance between them is increased,then the two nodes stops communicating.can you help me out with solution for the above.

Below attached is the code of PLC.Thanks in advance.

Regards

Shafi