The FCC is set to ban LightSquared from going ahead with its proposed national wireless broadband network, following a government report concluding that it would interfere with navigation gear.
The National Telecommunications and Information Administration has written to FCC chairman Julius Genachowski saying there's no safe way to implement the 4G-LTE technology.
"Based on NTIA's independent analysis of the testing and analysis performed over the last several months, we conclude that LightSquared's proposed mobile broadband network will impact GPS services and that there is no practical way to mitigate the potential interference at this time," the letter reads.
"Furthermore, while GPS equipment manufacturers may be able to mitigate these issues via new technology in the future, the time and money required for federal, commercial and private sector users to replace technology in the field and the marketplace, on aircraft and in integrated national security systems cannot support the scheduled deployment of terrestrial services proposed by LightSquared."
It's by no means the first time that LightSquared has faced significant opposition to its plans. Last month, it protested that tests showing widespread interference from its system were rigged.
The problem is that it's actually the GPS systems that are 'bleeding' into LightSquared's frequency band, rather than the other way about - meaning that LightSquared feels it has right on its side.
Even now, it says it plans to carry on fighting.
"NTIA relies on interference standards that have never been used in this context, and were forced by the GPS community in order to reach the conclusions presented today," it says in a statement.
"This, together with a severely flawed testing process that relied on obsolete and niche devices, shows that the FCC should take the NTIA's recommendation with a generous helping of salt."
It calls on the FCC to carry on looking for a solution.