Phil Karn and I used this series when we were doing some calculation and
now Chris Bartram (Mutek front end fame and uwSDR founder) pointed this
series out. There appears to have a new section added: SDR in deep
space. This is a very very important link for RF communications
engineers dealing with space matters.
http://descanso.jpl.nasa.gov/Monograph/mono.cfm
Bob
The Center for Strategic and International Studies has released a report
titled "Health of the U.S. Space Industrial Base and the Impact of Export
Controls", available at:
http://diig-csis.org/calendar/detail.asp?EVENT_ID=261&MONTH_CHOICE=2&DAY_CH…
The Aerospace Industries Association states that the report "provides
quantifiable evidence that the U.S. space industrial base has been weakened by
U.S. export control policy for commercial satellites and their components.
Based on a government survey of more than 200 U.S. companies, the report
concludes that second- and third-tier suppliers, the source of much
innovation, have been hit especially hard since export sales are vital to help
offset their significant investments in research and development. The report
identifies practical recommendations to improve controls on commercial
satellites and components while still ensuring these technologies are
protected appropriately."
Some particularly relevant passages:
Finding 9: Some elements of the export controls laws are in conflict with US
National Space Policy.
Finding 6: The current export control policy has not prevented the rise of
foreign space capabilities and in some cases has encouraged it.
Finding 11: The US is the only country that classifies commercial
communications satellites as "munitions".
Dan Schultz N8FGV
I regret to inform the Eagle group that at Juan's request, he is no
longer in the Eagle project and is not available to work on AMSAT
projects and has even gone so far as to resign, not renew, or not get
an AMSAT membership.
I really do regret this. I tried, almost at the expense of another
friendship, to make this work. But in the end Juan had an agenda that
was inconsistent with AMSAT's, and he was VERY critical of AMSAT without
being proactive in helping with corrective actions. His agenda moved to
taking on the entire development of the Intelsat payload by
professionals in the Bay area and with a seven figure number as the
cost. It moved steadily from volunteers to employment. When I asked
for the CV of the people he wanted to involve, it lead to a an
explosion and quitting as the request of CV's from people he wanted me
to pay millions was an insult. I was supposed to take his word to come
to a meeting where they would tell me what we should do. I just could
not go down the path he wanted. I want to remind everyone here of an
explosion that Juan mounted last year. I suggested that we might need
to begin outsourcing some work. He exploded and said that it was
inconsistent with AMSAT work. Now, he leaves because he wanted to do
exactly that and views all my attempts to get information as some kind
of insult or invasion of territory.
I hope you all know that we never like to lose volunteers for any reason
if it can be helped and if any of you remember my awards at Pittsburgh,
you know I singled Juan out for "MVP" for 2007. This was done in
conjunction with Jim Sanford. Juan did us a lot of good in 2007 and I
wish this could have worked out. My apologies to the group for this
disruption and I accept blame and responsibility for this loss but I
just could not go forward.
I will directly work with John to work out arrangements for finishing
the rework of the 70 cm receiver. As a result of our very successful
relationship with Juan, I have many questions that Jan King, Karl
Meinzer, and many others in this list completely missed in the review.
It would be easy to see looking at the group that did the review how one
might get complacent.
I have a plan to move the RX forward. I will be asking the individual I
wish to involve this week.
Bob
I've been thinking about how the use of mode UV might change with a
geostationary satellite. It could allow for the use of very simple antennas
for mobile operation as was done with AO-16. Since the satellite is
stabilized and fairly large, it may be possible for AMSAT to procure
space for a broadside array with at least 2 elements on 2 meters with
vertical polarization. This would give 8 or 9 dBi of gain and be
compatible with 1/4-wavelength whip antennas mounted on automobiles
in mid-latitude locations. It would also allow the speed of the currently
planned digital uplinks and downlink to be increased.
This digital downlink could allow multi-user digital voice operation with
fairly low power given that 2400 and 1200 bps MELP vocoders are now
available. 50 kHz could allocated for SSB and 50 kHz for a TDM digital
downlink. A 24 kBaud QPSK downlink could handle 10-20 users using a rate 1/2
error correcting code. If we assume that the man-made noise level is 6 dB
above the thermal noise level, a 1 dB NF LNA, 6 dB SNR and a 32 kHz
bandwidth for the downlink signal, -116 dBm is required at the receiver.
Path loss is 168 dB, so at least 52 dBm EIRP is required from the satellite
which means 20-25 W of transmitter output. This seems feasible for the
HELAPS transmiter or there could be a separate transmitter and a high-level
power combiner.
Both 70-cm analog and digital uplinks could be handled by a common receiver
using a short (1 m) yagi antenna or a broadside array.
73,
John
KD6OZH
AMSAT Engineering needs experienced help programming MPS-430. This
processor will be in a Cubesat. It would be my preference for us to use
FreeRTOS on it but this is not a decision I will mandate if adequate
reasons for not following this path can be provided. Email me directly.
Bob
Apologies for the private email sent publicly:
Chuck I have tried to send you several emails. Please respond to me
directly with your new email address.
Thanks for the bandwidth.
73's
Bob
All,
I arrive at Orlando airport after 4pm today. The hotel is 22 miles away. I
rented a 7 passenger van to help with transportation over the weekend.
Anyone who wants transportation this afternoon from the airport should call
me on my cell phone (see below). So I know to wait for you. I will be
waiting for Tom Clark who arrives an hour later so you can call any time
before 5pm.
Rick
W2GPS
AMSAT LM2232
Richard M. Hambly, CNS Systems, Inc.
363 Hawick Court, Severna Park, MD 21146
410-987-7835 phone, 410-987-7836 Fax, 410-299-2147 cell
<mailto:[email protected]> rick(a)cnssys.com, <http://www.cnssys.com>
www.cnssys.com, <http://www.gpstime.com> www.gpstime.com
_____
From: Rick Hambly (W2GPS) [mailto:[email protected]]
Sent: Wednesday, January 30, 2008 5:56 PM
To: 'John.Klingelhoeffer(a)verizon.net'
Cc: Robert McGwier (rwmcgwier(a)gmail.com); 'Tom Clark, K3IO'; 'Martha';
'Barry A. Baines'; Elaine Hambly (elaine(a)cnssys.com)
Subject: Orlando Trip, Flight Itinerary
All,
Here is my flight itinerary for the Orlando trip.
AirTran Airways.
February 07, 2008, Flight 472 [Non-Stop] Seat: 22F
Departing Baltimore/Washington, MD (BWI) at 02:04 PM
Arriving Orlando, FL (MCO) at 04:14 PM
February 11, 2008, Flight 470 [Non-Stop] Seat: 22F
Departing Orlando, FL (MCO) at 04:51 PM
Arriving Baltimore/Washington, MD (BWI) at 06:57 PM
Payment Information:
Ticket Total 266.00
Rick
W2GPS
AMSAT LM2232