Definitely, there are MACs whose form of carrier sense is
detecting preamble rather than detecting energy. In my same
piece of work, we put a matched filter in the FPGA and the
host specifies the coefficients of the match filter, then you
gate on that. But, I don't think it's unreasonable to think
basic energy detection is not general purpose enough? I think
supporting some basic form of energy detection would start to
enable better MAC implementations...
and afterwards I have every intention of rolling a match
filter in to the FPGA also. So, maybe your suggestion is I
build a separate FPGA implementation if people want MAC
functionality. I can do that if people believe that the
functionality is not general enough.