Are there any network protocol that we can use at competition?

[Zholl]

Going to have to agree with Eric here. The purpose of the rule restricting teams setting up wireless access has generally been to cut down on the amount of wireless interference on the field. 802.11ad may get around this problem since it runs at 60GHz, however just because it doesn't directly interfere with b/g/n wireless doesn't mean it can't produce interference with that spectrum. Also, it's such a new standard that I can foresee two problems with you attempting to use it: 1) you can't get equipment to work with it/have to buy all new equipment to use it, and 2) the volunteer staff won't be aware/knowledgeable enough on the standard to know whether or not it interferes with the field wireless, and you'll be asked to shut it down anyways.

Bluetooth could also be problematic. It's range and speed are pretty heavily limited in comparison to the 802.11 standards, and may not be effective for your purposes as a LAN, which is why it's typically only used in Personal Area Networks anyways. Also, while it's much lower power, it does still operate in the 2.4GHz range, and will directly interfere with WiFi.

Cellular data may work, though not easily if you're looking for a LAN setup. You may need to setup a team VPN to make that work as a local network. And depending on the venue that may not be feasible just because of coverage or speed issues, not to mention that you may not have enough team members willing to pay for the data that ends up getting used.

Unfortunately, there's probably not a simple way for you to set this up that does not violate the rules on establishing a wireless network at competition, at least if you're needing a significant amount of range. I'd personally just go the GP route and come up some system that falls completely in line with the rules set out by FIRST, instead of trying to get around them on a technicality. Perhaps a line of sight IR laser transmission?