CubeBUG-1

The Capitán Beto (AKA CubeBUG-1)

Mission

CubeBug-1 ModelCubeBug-1 is the first technology demonstration mission for a new cubesat platform design (mechanics, hardware and software) intended to be released as Open Source and Open Hardware for its use in Amateur projects, University projects and research labs. This project is sponsored by the Argentinian Ministry of Science, Technology and Productive Innovation, INVAP S.E., Satellogic S.A., and Radio Club Bariloche.

As payload on this first mission, some custom designed components will be tested: an ARM based on-board computer, a nano-reaction wheel with its driver circuit and a low resolution camera, all based on COTS components. CubeBug-1 is expected to be launched as part of a group of cubesats in a DNEPR rocket launch planned for September 2012 from Yasny launch base, in Orenburg, Russia.

After the technology demonstration part of the mission is over, the satellite will enter a mode that will include services to the Amateur radio community, including a Digipeter and science data downloads from the payload.

Orbital parameters

Name                 CubeBUG-1
NORAD                39153
COSPAR designation   2013-018-D
Inclination          98.035
RA of A. Node        351.212
Eccentricity         0.0018455
Argument of Perigee  21.587
Revs per day         14.77969514
Period               1h 37m 25s (97.42 min)
Semi-major axis      7 014 km
Perigee x Apogee     623 x 649 km
BStar (drag term)    0.000241260 1/ER
Mean anomaly         338.613

Downlink

Beacon

437438 MHz 437445 MHz. AFSK AX.25, 1200 bps

Call

CUBEB1

Preliminarily TLE

CUBEBUG-1
1 39153U 13018D   13117.77950566 -.00009058  00000-0 -12981-2 0    79
2 39153  98.0793 193.5309 0016761 243.0339 116.8958 14.76296739   242

Telemetry

The source of the AX.25 packet is labeled as “CUBEB” and destination “UI”. The data portion contains a binary blob. There are mainly two beacon formats. Packets starting with FF FF F0 are the complete beacon, packets starting with FF FF F3 are a short beacon, with basic information, and a different encoding. All numbers in the packets are stored in network byte ordering (Big Endinan). Most values require a conversion formula, provided in the next table.

CubeBug-1 Telemetry

The short beacon is encoded a bit different. For every bit the satellite wants to transmit it actually transmits 4. So, for example, the 8 bits 0xA5 become F0F00F0F in the air (a nibble per bit). As this encoding transmits more energy with each bit, it will give us a chance to decode some basic telemetry in a worse scenario. The first three bytes (FF FF F3) identify the packet as a short telemetry beacon, the rest must be “decoded” before interpretation.

CubeBug-1 Telemetry

Status

Launched and active. Will be launched by a Chinese Long March 2 on April 26, 2013.

Here is an image where you can see a carrier with very weak sidebands this data was received on April 26, 2013 around 12:00 UTC.

CubeBUG-1 TLE 26-04-2013 12:20 UTC


Homepage and other references:

CubeBug-1 Satellite information.