My job is to collect data from environmental stations and we use cellular modems for that. For LTE modems (we have a lot of old EVDOs) we buy expensive antennas and need two of them. This is normal for the field as we have to do our best to get a strong signal as often there aren't many towers around. However, for setting up and testing cellular modems in my office (which has a typical urban environment), I find that using just one of these modems works very well, is easy to slip on and off, and doesn't get in the way, etc.
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