BLUEWALKER-3 & BLUEBIRD1-5 (AST)

    • New

    AST based on a CubeSat:

    Light-1, which is a 3U cubesat from United Arab Emirates (this was first discovered by Tetsurou Satou JA0CAW). The framing contains the typical elements of the built-in packet handler of low cost FSK chips such as the Texas Instruments CC11xx family. Scott Tilley noticed some details that seem to explain this connection: Light-1 was built by NanoAvionics, which apparently has collaborated with AST SpaceMobile in the BlueWalker 3 mission. Therefore, it seems that the satellite bus used by BlueWalker 3 is that of a typical cubesat.


    Would it make sense to complain directly at AST Spacemobile? As far as I am aware the next generation of the birds at AST is not finally designed.

    • New

    Yes, it's no secret that BlueWalker 3 was a NanoAvionics cubesat from Lithuania with a huge foldable antenna attached. These new satellites seem to be the same. They even use the same protocol on UHF.

    The reason they're preferring UHF instead of S-band for TTC is that they got zero complaints for requesting UHF. In S-band uplink you often get lots of complaints from NASA. You can see all the limitations they've gotten in this grant related to avoiding interference to NASA satellites.


    Reading the FCC grant carefully, it is clear that the UHF grant is only for communications with the 5 groundstations (all outside the US!!) listed at the end of the document. The grant doesn't allow continuous beaconing as they're doing!!

    The major point is that AST are transmitting over the US on UHF, which shows that they're even not at all following what the FCC grant says. Perhaps because they think nobody will observe and complain. In this respect, the FCC might want to find them or at least call them to order. ARRL/AMSAT-NA are the best to complain by providing evidence collected by SatNOGS because they're US entities.


    Even though doing TTC with 5 particular groundstations in amateur spectrum still seems unfair, continuously beaconing worldwide (and with a rather high duty cycle) is orders of magnitude worse.


    Observations using SatNOGS seem to be constantly beaconing, including inside the US (example: https://network.satnogs.org/observations/10234701/).


    It might be reasonable to fill in a complain with the FCC. Primarily though AMSAT NA and/or ARRL, but all other's like AMSAT-UK / RSGB, AMSAT-F, AMSAT-HB, DARC, etc.. should also act accordingly. AMSAT-DL is already in touch with DARC and IARU.


    It's strategically important for amateur radio, to act strong as a community in this case. If this slips without consequences, then it sets precedent for more cases of the same, whether it's all the future 243 AST satellites, or someone else's.

    • New

    It would be good to collect interference and potential interference on those frequencies used by BlueBird 1-5. For sure someone will ask for it. A lot of people might even not be aware were it is originating from. For example Repeaters on 439.5 MHz or 430.5 MHz (Repeater input in UK).

    • 430.5 MHz
    • 432.3 MHz
    • 434.1 MHz
    • 435.9 MHz
    • 439.5 MHz