Hi,
Please read the documentation on how to add a new module in NS-3 and particular to the NS-3.18 version
This is based on the NS-3.11. There are a few changes in the structure/wscript file since then.
1) You do not add the jamming-module.h, you have to ADD the complete jamming-module folder inside /src
Also there are changes in existing modules, wifi in particular. You should change the interference/preamble files.
2) There is no patch for NS-3.18 available. Contributions are welcomed.