CubeSats Galore!

No the Phonesats don’t look like this!

It is an interesting time if you are into chasing satellites as there is a plethora of CubeSat launches imminent.

Last night I settled down and logged into NASA-TV to watch the Orbital Sciences Antares Test Flight (A-ONE Misson) Antares is a new medium-class space launch vehicle. Following this test launch and a further demonstration mission it will hopefully become a cargo deliverly system to the International Space Station (ISS)

As part of this initial test there were a number of CubeSats on board due for deployment unfortunately with just twelve minutes on the clock the launch was halted due to a premature separation of a launch pad umbilical connection to the Antares upper stage used for data communications. Orbital is currently analysing what happened. The next launch attempt is tentatively set for no earlier than Friday pending a successful resolution of the issue and acceptable weather conditions.

The CubeSats due for deployment were part of the NASA PhoneSat project. Three CubeSats called Alexandra, Graham and Bell are 1U sized and similar to the British STRaND-1 CubeSat utilise Commericial Off-The-Shelf (COTS) Electronics, namely a HTC Nexus One smartphone running the Android operating system for the Phonesat 1.0 satellites (Graham and Bell) and a Samsung Nexus S for the Phonesat 2.0 Beta satellite (Alexandra) The satellites also contain an external radio beacon, batteries and a circuit to reboot the phone if it stops transmitting, again all off the shelf commerical parts.

All three satellites are emitting packet transmission over the amateur radio band at 437.425 MHz, utilising the call sign KJ6KRW and will be spaced apart to allow reception of all three during a single pass. More details are available at http://www.phonesat.org

Also onboard Antares was the commericial DOVE-1 satellite, a technology development experiment. Originally intended to have a telemetry downlink on 145.825MHz this apparently is no longer the case.

More information about the Antares payload is at http://amsat-uk.org/2013/04/16/antares-cubesat-launch/

If the Antares does launch on Friday, it will share the skys with Soyuz-2-1a which is due to be launched at 10:00UTC from Baikonur in Kazakhstan. Amongst its payload are four CubeSats with amateur radio payloads, OSSI-1, BEESAT-2, BEESAT-3 and SOMP. Again more details can be found at the AMSAT-UK website at http://amsat-uk.org/2013/04/17/soyuz-cubesat-launch/

Also next week the launch of CZ-2D from the Jiuquan Space Centre is planned on April 26, carrying the Mode J (145/435) linear transponder satellite TURKSAT-3USAT along with the Argentine CubeBug-1 and Ecuadorian NEE-01 Pegasus TV Cubesat

TURKSAT-3USAT – http://amsat-uk.org/satellites/turksat-3usat/
CubeBug-1 – http://amsat-uk.org/2013/03/22/cubebug-1/
NEE-01 Pegasus – http://amsat-uk.org/?p=14689

So it looks like being a busy time, once the orbits are known and the TLEs are published.

Sadly it seems STRaND-1, that got me so excited last month has fallen silent after its transmissions became intermittent over the Easter weekend. After failing to receive any radio transmissions the team are apparently asking the EME weak-signal community to listen for the STRaND-1 LO (Local Oscillator) at 312.5MHz to see if it is still alive.

I think I might be mad!

I know it is difficult to believe but Spring is officially here! At 11:02 today the vernal equinox occurred.

Well earlier at 07:00 I was standing out in a snow shower with the 2m yagi monitoring the ISS downlink on 145.800MHz. This was a school contact with Australia being operated via a telebridge using an Italian ground station. Details here http://www.southgatearc.org/news/march2013/ariss_event_2003.htm

I did get a reasonable signal during the pass but sadly it was marred yet again by interference.

The weather is dreadful at the moment, the picture above shows the view out of the shack window last Sunday afternoon. I had hoped to capture various satellite transmissions but the weather was atrocious. It rained most of the day and then around 14:00 it turned into a short lived heavy snow shower.

On Monday night I went to catch the evening pass of STRaND-1 and AAUSAT3 only for it to start raining once I had got set up!

STRaND-1 – I think I have a faulty antenna!

Over the weekend I have made a couple of attempts at receiving the STRaND-1 satellite telemetry and indeed have a few IQ wave files that require processing but I don’t expect to get any successful decodes out of them as they have been rather patchy and variable.

During the pass on Sunday evening I wasn’t getting anything and as it neared the end of the predicted pass I gave up and picked up the antenna tripod to put it away and suddenly a strong signal appeared on the SDR waterfall! I suspect I have a problem with the antenna, either a faulty connection in the coax or connectors that was briefly corrected by the act of moving the tripod. It isn’t the first time I have had issues and will have to investigate further.

The weekend wasn’t a total loss, I did manage to capture a reasonable NOAA-18 pass on Sunday afternoon! Between washing the cars and doing some gardening!

STRaND-1 – First attempts

As I posted earlier this week a number of satellites were launched into orbit on board the PSLV-C20 rocket, this included the first UK CubeSat, STRaND-1.

STRaND stands for Surrey Training, Research and Nanosatellite Demonstration and STRaND-1 is hopefully the first of a long line of STRaND nanosatellites from the academic researchers at the Surrey Space Centre (SSC) based at the University of Surrey in conjuction with Surrey Satellite Technologies Limited (SSTL).

The innovative STRaND-1 CubeSat was built and tested in just three months and is designed to demonstrate the feasibility of using cheap smartphone electronics to control a spacecraft, since it contains a Google Nexus One Android phone as part of its experimental payload. STRaND-1 carries an amateur radio AX.25 packet radio downlink on 437.568 MHz using 9k6 bps FSK modulated data HDLC frame, NRZI encoding.

Official orbital elements (TLEs) have already been produced so the current position and prediction passes can be calculated and available on n2yo.com

At the time of this post STRaND-1 is passing over in UK in the early morning (South-North) and early evening (North-South), both times are not particularly convenient on weekdays due to work commitments, but last night I did manage to have my first proper attempt to capture some of the telemetry.

My ‘ground station’ consisted of a FUNCube Dongle and SDR-Radio (V1.5) with doppler correction enabled. It was connected to a small Moonraker ZL-Special 7-element antenna mounted on a small tripod with my Android phone running the Satellite-AR application mounted behind it. The Satellite-AR assists in pointing it in the correct direction as the pictures below demonstrate.

This slightly blury picture shows the satellite cluster containing STRaND-1 displayed in the Satellite-AR app, by moving the antenna on the tripod I attempt to keep this in the centre of the screen hopefully maximising the signal.

As you can see on the waterfall I did manage to receive the telemetry signal. It isn’t a continuous signal, data is broadcast in short bursts with long gaps between the ‘frames’

The next stage was to take this and using a number of software packages, including a TNC modem emulator and extract the data. The process is described here by Jan van Gils (PE0SAT) I have had a few attempts with my captured signals, unfortunately with little success I think due to the signal to noise ratio being too low.

This morning I was up nice and early to capture the pass at approximately 05:50, this time I used my FUNCube Dongle Pro Plus on another laptop, but for some reason the received signal was very poor. In desperation I took the antenna off the tripod and held it horizontally rather than vertically and did manage to get a signal, unfortunately it was at the end of the pass and STRaND-1 was heading over the horizon.

Still I am happy with my initial efforts.

STRaND-1 Cubesat

Right I have put the CB to one side, it has sadly proved very frustrating but more on that another time.

The current buzz are the newly launched satellites, including STRaND-1 http://amsat-uk.org/tag/strand-1/

This satellite has received quite a bit of media coverage by virtue of the fact it is carrying an Android Google Nexus-One smartphone as part of its payload. (BBC new article)

So I’ve blown the dust off the the FUNCube Dongles and removed the cobwebs of the 70cm Yagi and am planning on waving it at the sky in the early evening trying to capture some of the telemetry transmissions on 437.568MHz.