> the students were supposed to each get a software radio and build a Wi-Fi-like system (the software radios proved difficult and, much later, I helped make this an acoustic modem project).
What was the reason why the software radios proved difficult?
Not OP but in general sourcing software and hardware radios in that time was very difficult. There weren’t good open-source implementations and everything had to be sorta reverse engineered which meant that anyone with the skill to do that was selling it for a lot of dollars.
A semi-off-topic side question:
> the students were supposed to each get a software radio and build a Wi-Fi-like system (the software radios proved difficult and, much later, I helped make this an acoustic modem project).
What was the reason why the software radios proved difficult?