I have worked on 25kw units for aircraft (California fish and game) that can
see seagulls at 3/4 mile and measure fishing nets floating in the water.
This is how they busted the commercial fishermen that put out more net than
they were allowed.
The Magic here was in the digital processing to filter out the noise.
You can ether use lots of power or lots of processing power, these days the
processing power is cheaper and safer.