Use of 430-440 MHz by AST SpaceMobile constellation

Image by PE0SAT of 435.900 MHz downlink received Sept 12, 2024

AST & Science LLC (AST SpaceMobile) currently have five Bluebird satellites, launched 12 September 2024, in Low Earth Orbit using the amateur radio 430-440 MHz band, see
https://community.libre.space/t/asts-bluebird-1-5/12255

These amateur frequencies are used for the uplink and downlinks with up to 50 kHz bandwidth 430.5, 432.3, 434.1, 435.9 and 439.5 MHz.

AST say they have ground stations in Australia, Argentina, Bulgaria and Korea.

They are planning to launch a further 243 satellites also using 430-440 MHz and in February submitted a request for use of those amateur frequencies to the FCC Space Bureau
https://apps.fcc.gov/els/GetAtt.html?id=371448&x=.

In April the FCC responded with these questions to AST
https://forum.amsat-dl.org/cms/index.php?file-download/7502/

AST’s responded in May to the FCC questions regarding their filing, see answer regarding IARU
https://apps.fcc.gov/els/GetAtt.html?id=376295

The Interference Analysis Report submitted by AST in their answer doesn’t mention the interference that would be caused from the 430-440 MHz transmissions, see
https://apps.fcc.gov/els/GetAtt.html?id=373778&x=.

FCC issued this Public Notice in June – comment to FCC by July 21
https://www.fcc.gov/document/space-bureau-accepts-filing-ast-science-llc-application

For some background on FCC attitudes see the interview the Chief of the FCC’s Space Bureau, Jay Schwarz, gave to the American Enterprise Institute (AEI). It primarily concerns the ITU-R EPFD limits but it reflects the new thinking at the FCC about getting rid of “outdated assumptions about system design and spectrum use”
https://www.aei.org/technology-and-innovation/how-the-fcc-space-bureau-is-rethinking-the-rules-of-space/

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AMSAT-UK