I’ve spoken with a contact who has a great deal of experience in the industry and here are his thoughts on this issue:
"This is a huge challenge for exhibitors and organisers and generally speaking it’s not always the organisers fault as you are putting X amount of visitors and exhibitors in the same place and asking them to feed from the same network at the same time which obviously puts a huge drain on connection. The bigger the show the bigger the problem unfortunately! If his hotspots aren’t working then this is more a service provider issue and maybe he needs to look at a new supplier. Alternatively he should look at investing in a portable WiFi booster for mobile. If it’s a laptop connectivity issue he should look at a plug in option. This unfortunately is not an issue that has a one fix option as the biggest part of this is the venue investing in the very best(often the most expensive) wireless package for venues but a lot of them simply won’t do it. As an exhibitor he may need to forego location to be nearer the main signal with a stand near/beside it. Personally I would be asking questions of his current supplier and invest in a portable modem as this gives him the best option."
Hope that helps!