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Smart1 Lunar orbiter reception



All,

There are some interesting Amateur reception reports at S band, including
the Smart1 lunar probe, at:
http://www.uhf-satcom.com/sband/

(Smart1 is generating 5 watts into a 12dBi antenna. The example on that
site, uses a 2Hz FFT bandwidth and a 1.5mtr dish, so the link budget is
about 27dB higher than Dave's forecast. Hence the 20dB SNR that is shown.)

There is also some spacecraft data at:
http://www.ssc.se/data/content/DOCUMENTS/2004102215175913smart1.pdf

Jules
G0NZO


Date: Mon, 19 Jun 2006 20:08:03 EDT
From: G0MRF@aol.com
Subject: Re: [amsat-bb] Lunar Orbits

Hello Trevor.

Looking through the NASA site, it appears the recent SMART-1 mission, which
used the Xenon-Ion drive, achieved orbit in November 2004 and is expected to
crash on the surface in 2 months time. So, that one orbited for a little
under
 two years.
Thinking of amateur radio beacons: The path loss on 2.4GHz is about 212dB.
A
quick look at signals suggests a 1W ERP signal could be detected in a 100Hz
bandwidth with a 1m dish.
For a beacon running a JT65 type signal, 1W would be QRO. Although keeping
accurate time while in moon orbit may be a little tricky.

Regards

David G0MRF




"Lunar orbit capture occurred on 13 November 2004 at a distance of 60,000
km
from the lunar surface. The ion engine began firing in orbit at 05:24 UT
(12:24 a.m. EST) on 15 November to start a 4.5 day period of thrust to lower
the
orbit. The first perilune took place on 15 November at 17:48 UTC (12:48 p.m.
EST) at an altitude of about 5000 km above the lunar surface. The engine was
then used to lower the initial 4962 x 51477 km altitude, 5 day, 9 hour
period,  81 degree inclination orbit, putting SMART-1 into a 300 x 3000 km
polar
orbit.  Lunar commissioning began in mid-January 2005 and lunar science
operations in  February 2005. The mission has been extended from its
originally planned
6-month  lifetime by a year, so it will now conduct mapping of the Moon's
surface and  evaluating the new technologies onboard from lunar orbit until
August 2006. The  xenon-ion engine was shut down in September 2005 after
exhausting
its fuel  supply. It operated for almost 5000 hours and underwent 843 starts
and stops.  SMART-1 is expected to crash into the Moon on 17 August 2006
----
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