[Starlink] Re: Starlink and Iran

David Lang
2026-01-17T00:08:00Z

Ulrich Speidel wrote:

> On 17/01/2026 8:03 am, Michael Richardson wrote:

>> Ulrich Speidel via Starlink <starlink@lists.bufferbloat.net> wrote:

>> here. Why? Because there is a limit on the amount of power per square metre
>> and MHz of bandwidth (EPFD) that systems such as Starlink may project onto
>> the surface of the Earth. It's an ITU-imposed limit, so the FCC can't really
>> do much about it. SpaceX are on public record for not being happy with it and
>> with their v2's they're riding right up against that limit.

>> 1. Who checks/enforces this ITU limit?

> The licensing authorities in the respective countries (i.e., the FCC in the
> US - and they're held to account by their competitors, of which SpaceX has a
> few in the US). At an international level, if one country were to ignore
> this, so would everyone else, which would make space-to-ground comms in these
> bands pretty unworkable pretty quickly as there'd be a lot of "my output
> power is bigger than yours" happening. One of the main reasons for having
> this limit is to ensure GEO sats can get their signals through. Whether the
> current level that the limit is set at and the way it's computed is
> appropriate is another question, and SpaceX have certainly tried to litigate
> that before the FCC.

have you looked at what the latest changes allow?

>> 2. Could the physically satellites go higher over some territory? How much
>> higher?

>> I assume it's software controlled.

> A satellite has three types of energy that determine its orbital motion:
> Potential energy from orbital height, kinetic energy from moving, and energy
> stored in its thruster fuel.

I think he's talking about the radio energy at the receiver, not satellite
energy.

David Lang