so, alex smith walked in front of the frequency cart, it looks like they're using these:
RTS RKP-4B 4-Position Wireless UHF Keypanel-Base Station[]=60&fam[]=61&fam[]=68
which is telex encrypted UHF intercom. the rkp-4 replaces the BTR-1. i could be wrong, it was only on screen for like 2 seconds. I think they had one guy go to all the stadiums so the equipment is standardized as far as initial planning, but then it's up to the teams or game crew to run it (from something i saw a while back).
nascar has a company called racing radios that does basically all the setup etc for their stuff (initial and per race), everything's ordered through them, but it's mainly motorola TRBO based stuff, so it's 4-5watt UHF LMRs more or less.
for UHF line of sight is super important. VHF bends around things a bit more (they tested a vhf digital intercom system at the pro-bowl).
sorry if that's way off topic. it's a continuation of a post in the headset issue thread from last week.