At the 2014 AMSAT Space Symposium AMSAT Vice President – Engineering Jerry Buxton announced the plan for the next generation of AMSAT satellites. “The door is open for everyone, to submit their ideas. AMSAT Engineering has a long term strategy and this is the first step.”
The Engineering long term strategy includes the following goals
- Advancement of amateur radio satellite technical and communications skills
- Enhance international goodwill
- Grow and sustain a skilled pool of amateur radio satellite engineers
- Establish and maintain partnerships with educational institutions
- Develop a means to use hardware common to all opportunities
With respect to the last goal Jerry said “Within the bounds of the type of satellite it takes to achieve any of the various orbit opportunities, let’s consider in those plans the possibility of developing a platform that can suit any and all orbits. Perhaps a modular CubeSat, using a common bus as we did in Fox-1, which gives great flexibility in building and flying different sizes and configurations of CubeSats with simple common-design hardware changes.”
Submissions should be thorough and contain the following information. The purpose of the proposal is not just in suggesting an idea; being an all-volunteer team AMSAT needs your help in carrying out the idea.
- Implementation – CubeSat platform
- Estimated timeline
- Cost – volunteer resources, commercial (COTS) units
- Launch – how does it get to orbit
- Strategy – how it fits into AMSAT’s Engineering long term strategy
As mentioned above the idea should be based on the CubeSat platform. This is the standard through which we will look for launches in the foreseeable future.
The Fox-1A Engineering Unit transponder was on the air at 2014 Space Symposium. Attendees were able to work each other through the transponder and pose for pictures while holding the actual engineering unit. In addition, the slow speed telemetry that accompanies every voice ID beacon and transponder conversation was being received, decoded, and displayed for all to see.
Fox-1A Engineering Unit and Telemetry Display
W2BFJ and WD9EWK have a DX QSO
CO6CBF with Fox-1A EU
Pictures of some of the Fox-1A flight unit/spare systems, fresh out of the conformal coating process.
Fox-1A IHU system used in the flight spare
Fox-1A PSU system used in the flight unit
The Fox-1 series of satellites feature a slow speed telemetry, with 200 bps data being sent along with the transponder audio or voice ID activity. This allows telemetry to be sent continuously during normal transponder operation while QSOs are taking place.
The slow speed data is contained in the audio spectrum below 300 Hz. Using DSP techniques, high pass filtering is applied to the uplink signal and voice IDs, low pass filtering is applied to the telemetry audio which is generated by the IHU, and the combined audio is sent on the downlink as the voice and data. Forward error correction added to the downlink stream provides data recovery for up to 1/4 second signal fades.
Screen print of actual Fox-1A downlink slow speed telemetry received over the air on a FUNcube Dongle Pro+ with SDR# and a decoded/displayed with command line version of the AMSAT ground telemetry decoding software used in our testing
The slow speed data on Fox-1A contains four different payload types: Current telemetry readings, High telemetry readings, Low telemetry readings, and Vanderbilt University radiation experiment telemetry. The payloads are transmitted in a scheduled rotation that delivers one payload or frame about every 5 seconds. Current telemetry is thus received every 15 seconds, experiment telemetry is received about twice every 15 seconds, and high or low telemetry received once every minute (alternating minutes between high and low).
The telemetry contains many satellite health and operation values, including readings such as solar panel output, battery voltages, temperatures from various areas of the satellite, IHU performance, and the Penn State University MEMS gyro experiment data.
AMSAT will be providing free GUI software for decoding and displaying both slow and high speed telemetry from the Fox-1 series of satellites, as we get closer to launch. The software will be similar to the user software that was provided for ARISSat-1.