LTE MODEM/ROUTER LBR20 external antenna connectors

Suesgirl, thank you for the reply. I've purchased something similar to your two discrete antennas, but it's in the form of an integrated pair (kind of like the old TV "rabbit ears") at the end of a cable with two connectors that plug into the SME ports on the ORBI. I've seen a small difference in signal strength, maybe 4dB. Two things you should be aware of; 1) In order for the ORBI's MIMO function to work, you need both antennas to be plugged in and 2) the antennas need to be cross polarized, that is, at right angles to each other, for best MIMO performance. Also, the plane of the "V" thus formed should be perpendicular to the  line between the MINO antenna and the cell tower you're connected to. Since you don't know where that may be (unless you have a mobile app like "Network Cell Info" installed on a device like your smart phone) you'll need to play with direction and location of the antenna. With MIMO, it's not always all about raw signal strength. From the down and up speeds you're getting I'd guess you live in a fairly decent signal area. Here's a link to a useful You Tube video explaining some of this:  MIMO vs Boosters: Do Cellular Boosters Provide the Best Signal & Data Performance? - YouTube