Pointing will be harder as the beamwidth decreases by 44%. I'd rather have an L-band uplink as its cheaper to generate RF for high data rate uplinks. However, its easier for us to solve engineering problems than regulatory problems.
Hams are using 12-foot TVRO dishes with COTS positioners for 10 GHz EME. When I lived in LA, I had a 2-foot dish for 10 GHz that was mounted on a Yaseu el-az rotator. It was difficult to point but it worked.
73,
John KD6OZH
----- Original Message ----- From: "Matt Ettus" matt@ettus.com To: "John B. Stephensen" kd6ozh@comcast.net; "EAGLE" eagle@amsat.org Sent: Monday, September 11, 2006 01:48 UTC Subject: Re: [eagle] Re: DCP Bands
John B. Stephensen wrote:
Consideration of X-band was dropped early in the meeting, but should be
part
of the re-evaluation as a downlink band. I suspect that S2 is not viable
as
an uplink or downlink because of regulatory issues outside our region. If
S1
is unavailable and L remains a potential problem, C/X is a possible solution. The proposal in the U.K. to sell 10.125-10.225 and
10.475-10.575
GHz still leaves 10.450-10.475 GHz available for amateur satellites.
I do not believe X-band is viable.
As we said at the meeting, links with both sides gain-limited will get worse at 6dB per octave. Links with both sides aperture-limited get better at 6dB per octave. Links with one side gain and one side aperture limited stay constant.
Remember, the satellite side of the link is gain-limited, so that means that for everything to stay the same, we'd have to keep the same apertures on the ground. A 60cm and 1.8m dish at 10 GHz are very tough to aim with simple setups. What is the pointing accuracy required for a 1.8m 10 GHz dish?
Matt