[Discuss-gnuradio] How can I add channel encoder/decoder and equalizer in usrp_transmit_path.py and usrp_receive_path.py?

Hi:

I am new to gnuradio and have a question regarding how to build a communication link from scratch. 

This is the communication link I want to build:

Tx link: 

Data bit stream -> Hamming Coding -> QAM modulation -> add training sequence -> (send to the air)  

Rx link:

QAM demodulation  -> Decision feedback equalizer -> Hamming Decoding -> Bit stream

It seems that the existing gnuradio example usrp_transmit_path.py and usrp_receive_path.py don't have channel coding and equalization.

Does anyone know how to (1) add channel encoder and training sequence in usrp_transmit_path.py, and (2) add the equalizer and channel decoder in usrp_transmit_path.py?  

If it is too easy for a beginner to modify the example code, what could be a better way to build up such a communication link?

Thanks,

Rachel