ORIGINAL: mikehannah
Hi
Thanks for the steer. But it confirmed what I had drenged out of the back of my memory ( antenna theory never was my favourite subject and too be honest Maxwell's equations did my head in) but I did remember that flat Antennas were highly directional. So yes you get the gain but at a cost. That being said I am very curious what they have in that weatronics box.
But it doesnt answer my question. Why hasnt anyone else adopted a flat antenna?
M
Mike,
More than likely its because nobody else has a downlink - the Weatronics unit does. In order to get a reliable downlink at the distances our models fly, you have to have a higher gain than simple 1/4 wave dipoles can give you. In the research work I'm working on with NASA, we have a 5W transmitter on the aircraft (at 2.2450 GHz, but that's close enough to 2.4 to illustrate the problem), and a one meter steerable dish antenna that gives us more than 30 dB of gain. Still, at the distances that a jet can fly we get data dropouts. Yes, we are operating at a much higher bandwidth than the Weatronics unit needs to for its downlink, but the bottom line is, you need a high gain antenna on the ground to receive data from an aircraft...
Bob