Trying to get a Netgear C7800 to work without cable internet

[wifi-problems]

I live in a remote area, and the internet we have is provided via LTE signal to a BEC Airconnect 8110 Router, which then provides the wifi to our house. I had a Netgear C7800 in the garage and want to see if I can use it in addition to the Airconnect Router to provide better wifi to the house. So Airconnect receives the LTE signal, but then I want the C7800 to provide the wifi (attempting to do so via ethernet from the Airconnect)

I can only get ethernet out of the Airconnect, so I can't give the C7800 the coaxial cable that it usually receives. Any thoughts on ways to make this work? or is it even possible?

[plemans]

there used to be a work around to make it function as a sort of access point but I've heard a report or 2 of them auto-rebooting when they don't detect a coax signal. Not sure if that'd be the case with yours so you can try the work around. 

Follow this guide for the c6300. should still be the same process. 

https://community.netgear.com/t5/Cable-Modems-Routers/Can-I-use-a-C6300-cable-modem-without-cable-in...