Hello. Can you tell me if I can use antennas of this type for the frequency of 900 - 1200 MHz!
If not, what antennas could you recommend?
The installation will be outdoors.
The antenna is only specified for 868/915. The only way to know for sure if it works in the 900 - 1200 MHz range would be to measure it with a VNA.
Checking myself, I mean, is it possible to use this type of antennas or not?
It would highly depend on the frequencies desired and what you have to mount to
I will install it on a steel foundation.
Yes I don’t see why you couldn’t use an antenna like this, assuming it fits within your frequency requirement.