These terms describe RF design process rather than a partcular device:
The front-end of RFIC design includes system partitioning, functional simulation, behavioural modeling, schematic design etc and its back-end design includes layout drawing, DRC, LVS, parasitic extractions and back annotation etc.
front end invariably means the logic design using some HDL tools and their verification...
Then comes synthesis of the code..
in backend, the synthsised netlist is converted to gates on layout...