You will have seen adverts for devices of this type - they've become quite popular in recent
Operating on a frequency of 2.4GHz (that's 2,400,000,000Hz for
the uninitiated!), most have about 10mW or so output and while they work well
over a short range, the range is limited by the low power.
This design has much higher power - around 0.5W output, in
fact. So as you might expect, the range is very significantly extended. With the
simple coax cable "whip" antennas shown here, the range is reliably 200m or
more. But if you use a simple dipole antenna, you could expect much more range -
maybe 10 times or more.