albert ren has provided an update on cusat built by students at cornell university.
it is hoped cusat will be launched onboard a spacex rocket from kwajalein in the marshall islands later this year. a list of candidate payloads for the spacex falcon 1 launch in june can be seen at
http://lostzenpuppy.blogspot.com/cusat consists of two functionally identical satellites that will launch together and separate in orbit. image and positioning data will be downlinked using 9k6 ax25 packet on 70cms from a 2 watt transmitter. cross linking between the two parts will also take place on 70cms.
the international amateur radio union (iaru) has coordinated these frequencies for the mission:
cusat-1 437.405 mhz
cusat-2 437.485 mhz
cross link 437.305 mhz.
albert has posted this update on the amsat bulletin board (amsat-bb):
several weeks ago, nate parsons sent you all an email requesting assistance with our antenna setup on the satellite and ground stations. i just wanted to express our thanks and appreciation for all the help and advice that everyone provided to us, as it was very helpful and got us back on track. it's been a little while since that flurry of activity, so i thought i'd give you an update on how things have progressed since then.
because of the schedule and program constraints, we had to settle on a commercial-off-the-shelf solution for our space segment design. the antenna we ended up choosing was the comet sma-503 antenna. in a ridge test out at cornell, the results were much improved over the previous square-loop antenna design. in case anyone was wondering, the coating on the antenna is very easy to remove, but the base of the antenna should be left alone as that contains a matching circuit and is structurally necessary.
we also had the fortunate circumstance of a patch antenna becoming available to us, but unfortunately this design is too large to integrate onto the satellite.
on the ground station side, we've replaced the in-shack pre-amp that we had with a mast-mounted pre-amp that we bought from ssb. we have one ground station fully assembled at kwajalein in the marshall islands. the next big hurdle on that front is the software that we need to control the ground station. we've decided to write our own antenna tracking software, taking advantage of the fact that our ground station is essentially at the same location as the launch site.
currently, the antenna is undergoing final testing at the aef down at kirtland. we hope to ship the satellite out by the end of the next weekend in order to meet the schedule for the spacex launch, should we become the chosen payload.
again, thanks for all your help! please let us know if you have any questions or any other suggestions - we appreciate it all. we'll also keep you updated of any changes or news from the program.
regards,
albert ren
cusat ground segment lead
cusat website
http://cusat.cornell.edu/cusat youtube video
http://www.youtube.com/watch?v=iwgrt-ikntgspace exploration technologies corporation – spacex
http://www.spacex.com/iaru frequency co-ordination for cusat
http://www.amsat.org.uk/iaru/finishe....asp?serial=92join the amsat bulletin board amsat-bb at
http://www.amsat.org/amsat-new/tools...t/maillist.php
