Cubesats are small shoebox sized satellites that are usually designed by universities or amateur radio organizations for basic space experiments or amateur radio communications. Typically they have an orbit lifespan of only 3-6 months.
Cubesats typically transmit signals at around 435 MHz, and they are powerful enough to be received with a simple home made antenna and an RTL-SDR. To help with this Thomas N1SPY has created a YouTube video where he shows exactly how to construct a cheap eggbeater antenna made out of a few pieces of copper wire and an SO-239 UHF connector. Later in the video he demonstrates some Cubesats being received with his antenna, an RTL-SDR and the SDR-Console V3 software.
2018: Thomas N1SPY chases mini satellites on a budget
BY70-1 is a Chinese amateur Cubesat satellite which was recently launched on December 29, 2016. It is expected to stay in orbit for only 1 – 2 months due to a partial failure with the satellite releasing into an incorrect orbit. The purpose of the satellite is for education in schools and for amateur radio use. The receivable signals include an FM repeater and BPSK telemetry beacon both of which can be received at 436.2 MHz. The telemetry beacon is interesting because it also transmits images from an on board visible light camera. These signals can easily be received with an RTL-SDR or other SDR with an appropriate antenna.
Over on his blog Daneil Estevez has been posting about decoding these telemetry images. He’s been using telemetry data collected by other listeners, and the gr-satellites GNU Radio decoder which is capable of decoding the telemetry beacons on many amateur radio satellites. So far the decoded images haven’t been great, they’re just mostly black with nothing really discernible. Hopefully future decodes will show better images.
If you want to track the satellite and attempt a decode, the Satellite AR Android app has the satellite in its database.
Not many people seem to have gotten telemetry decodes or images yet, but below we show an image decoded by @bg2bhc on Twitter.
Recently, the FUNcube-1 satellite was successfully launched. The FUNcube is a CubeSat (a low cost miniature 10cm cube sized satellite) which is intended mainly for educating young people about radio, space, physics and electronics, but has also piqued the interest of amateur radio hobbyists.
Blogger and Amateur Radio enthusiast N4JTC has posted a guide on setting up a satellite receiving station with the rtl-sdr. Originally the guide was intended for receiving the PhoneSat test satellites, but they have now gone offline after a week as planned. But, the guide is still useful for any current and future satellites.
The recent launch of the PhoneSats got my SDR and satellite juices flowing again. This time I decided to automate things because work seems to get in the way of my satellite listening fun. I found a combination that works great and incorporates FREE software and inexpensive hardware.