Looking for satellite observations in UHF frequency outside of 420-450MHz

Hello everyone,

I am relatively inexperienced when it comes to sorting through the SatNOGS observations page. I figured it would be a good idea to start this discussion in the observations tab in case someone can help me.

I am part of a cubesat startup called UA Space and I am walking through the steps of filing for a frequency assignment. With our current satellite design, I am not sure that we will qualify with the IARU to use amateur radio frequencies in the UHF band for our satellite project (435-438MHz range) since we are not planning to add a transponder to our satellite. I was expecting to still go through the route of filing with IARU since the SatNOGS network has so many satellites and ground stations tuned to that range, but after reading through some forum posts (one linked below), Cubesat 101 (pages 44-48), and not hearing back from some contacts I had found in IARU, I am investigating just filing for an experimental license using special temporary authority (STA) using the UHF band (401 and 406 MHz based on the page 28 in the FCC Online Table of Frequency Allocations).

I am trying to find ground stations and satellites that might have used the UHF band outside of the amateur band, because we want to increase our chances of making observations by having multiple ground stations capable of receiving in this range. If anyone can provide some guidance or feedback on this approach, that would be very much appreciated. I hoping that someone might have already had a similar discussion in another post and that you could redirect me to it.

Thanks,
Chet Wiltshire
KO4AFB
Command and Data Handling Team Lead
uaspace.ua.edu

LINKS BELOW:

Continuing the discussion from Many satellite offer no perceived benefit for HAM radio:

Cubesat 101 https://www.nasa.gov/sites/default/files/atoms/files/nasa_csli_cubesat_101_508.pdf

IARU page for Amateur Radio Satellite Frequency Coordination
https://www.iaru.org/reference/satellites/

FCC ONLINE TABLE OF FREQUENCY ALLOCATIONS
https://transition.fcc.gov/oet/spectrum/table/fcctable.pdf

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Hello @ua_space Chet,

Thanks for reaching out to our community. I think there are two aspects that need to be discussed here: the technical one and the policy one.

Regarding the technical one, most UHF stations in SatNOGS should be able to receive a transmission in the 401-406 Mhz range without an issue. Albeit most equipment is tuned around 437Mhz but reception and demodulation should still be possible down there. E.g. check observations of NOUR-1 (for SSA purposes) or ARKYD-6A. From a legal standpoint the stations are signaling with their antenna selection if they want to receive transmissions in this band. So I would not expect any issue with that.

Regarding policy, that is a more complicated issue. In principle SatNOGS, as it currently operates, is a non-profit crowd-sourced ground station network with most stations being volunteers, with an emphasis on open data. In order to collaborate with a mission, we would need to know your status (non profit/for profit) and your stance around open data. Then if compatibility can be achieved, we generally ask for missions to contribute or sponsor a ground station setup to expand the network. Let us know more information about your mission and if you need any additional info about our operations.

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Hi @pierros,

I am so happy you found two satellites using 401 MHz (probably won’t find any in 406MHz since it is for uplink) because I wasn’t sure if there were observations in that range. This will be very useful information to share with my team so that may help convince them that it is okay to break out of the UHF amateur band and speed up our frequency assignment process.

I hope the information below answers some of your questions!

We are currently working on the SatNOGS version 3.1 rotator that we plan to add to the SatNOGS network, and we are currently working on getting the V2 rotator controller board working. I will save that discussion for the other boards, but I should add that this is a university project that is not for profit. Our radio that we choose for our mission might use encrypted packets (looking at different suppliers for UHF radio), but we plan to make the information for decoding our telemetry open for the public at this time. We plan to test a drag sail during our BAMA-1 mission and we are planning to beacon telemetry from our cubesat. We also plan to create and maintain a dashboard that we can use for technical and outreach purposes.

Respectfully,
Chet Wiltshire
KO4AFB
Command and Data Handling Team Lead
uaspace.ua.edu

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