Unmanned_droid, Situational awareness will vary between types of UAV, However with a fin mounted camera with a wide angle lens, you can have a pretty good view, and if the EO/IR ball is not being used to look at ground targets it can give a forward view as well, and the IR mode allows other nearby powered aircraft to be seen relatively easily.
Obviously you need a good up and downlink and an alert pilot on the ground if you are relying on see and avoid with a human in the loop.
With a fin-mounted IR camera and some software to see and avoid traffic with a sufficient heat signature, you can also avoid some traffic in autonomous modes. That just leaves gliders (inc. hang & para), gas balloons, parachutists, kites and birds to worry about. Additional cameras to cover blind spots are not heavy these days.
It does help to make sure your 'return home' program reflects your current address though
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https://www.strategypage.com/htmw/htairfo/20081229.aspx