It is well that the antenna plans are starting to congeal. I do have some comments upon the diagram that John presented, herewith attached.
1) There is an option, whether employed or not, that the U band could be the stacked CP patch design previously shown, with the L band array mounted thereon, also as previously shown.
2) The U band antenna currently shown in John's design could use a modification of the dipole design used for all of the AMSAT-DL P3 satellites. We call that "design adaptation" (not stealing!).
3) The V band antennas are of a great concern as shown in John's design. The P3D V antennas were more than 880mm end-to-end span, and a nominal 144mm spaced off of the spaceframe. Three of these on top of the Eagle seems to me to be of a gargantuan, unwieldy concept. These antennas would greatly impact the spacecraft envelop as mounting in a launcher. John has talked of a bent-end antenna design, is that really practical from an RF sense?
I am wondering if some form of dual-feed full-wave V band loop might not serve better in this application. Stan Wood had shown such a full-wave loop design for the Small Eagle that was only about 50mm high. Properly designed, it would not necessarily have to be 144mm high, so I am led to believe. Can some astute antenna designer look at this for us? I feel that we need to look at the options.
Dick Jansson --------------------------- mailto:rjansson@cfl.rr.com rjansson@cfl.rr.com ---------------------------
