Hello! 

I recently bought this router from a local seller and I want to use it with an internet operator that provides 4G internet through band 1 (2100). The problem is that the indoor signal is awful. Knowing the location of the cell tower, I was considering buying this directional antenna:

https://www.dipolnet.com/lte_mimo_antenna_atk-log_lte_800-2170mhz_10m_cable_sma_plug__A7056_10.htm

I know you don't recommend using aftermarket antennas, but this is the only thing I can do to get a good reception. I want to know if this router is compatible with the router an if it supports MIMO.