If the individual patches have too much gain it may restrict the offpointing angle. The beam needs to be steered 45 degrees off the spin axis. Doesn't this require that the individual patches have sufficient gain at that angle?
73,
John KD6OZH
----- Original Message ----- From: "Louis McFadin" w5did@amsat.org To: K3IO@verizon.net Cc: "John B. Stephensen" kd6ozh@comcast.net; "AMSAT Eagle" eagle@amsat.org Sent: Tuesday, September 26, 2006 15:28 UTC Subject: Re: [eagle] Re: Antenna Plans
Tom, Is there a special thing about having the 6 X 6 arrays square? Is the spacing between the element a specific number? Stan and I are going to look a making some patches in cavities like we have made for some of the small military satellites. We were able to obtain 8dB gain with those and they were circular polarized. Please give us the specific spacing and exact frequencies and we will see if we can make a prototype.
On Sep 26, 2006, at 2:09 AM, Tom Clark, K3IO wrote:
John B. Stephensen wrote:
Why not 4 entirely separate patches as far apart as possible or 3 patches next to the edges not occupied by the V antenna.
73,
John KD6OZH
If you consider the "remote" element along with all 6 elements along the [Bx By] baselines, we get a really easy way to resolve ambiguities rapidly. If you consider the 6+1 elements as an array, the net power pattern is the Fourier transform of the autocorrelation function. The sampling function ends up nearly complete with the geometry I showed. If I've confused the issue too much, wait for my antenna arraying papers at the symposium.
Tom
Via the Eagle mailing list courtesy of AMSAT-NA Eagle@amsat.org http://amsat.org/mailman/listinfo/eagle