"no clouds" is overstating the effect somewhat. I've operated a number of mission critical Ku band based systems that met four nines of overall link uptime. The operational effect of a cloud that isn't an active downpour of rain is negligible. Continual overcast of clouds is not much of a problem at all, it's active rain rate in mm/hour and its statistical likelihood, climate parameters of the location.

Yes, during rain fade events, current generation VSAT modems will drop all the way down to BPSK 1/2 code rate to maintain a link, with corresponding effect on real world throughput in kbps each direction, but entirely dropping a link is rare.



On Mon, Jul 6, 2020 at 9:40 PM Denys Fedoryshchenko <nuclearcat@nuclearcat.com> wrote:
On 2020-07-07 06:48, Eric Kuhnke wrote:
> This is why adaptive coding and modulation systems exist. Also dynamic
> channel size changes and advanced computationally intensive FECs.
>
> You don't think people working on microwave band projects above 10GHz
> with dollar figures in the hundreds of millions are unaware of basic
> rain fade and link budget methodology, do you?
>
> On Mon, Jul 6, 2020, 8:44 PM Denys Fedoryshchenko
> <nuclearcat@nuclearcat.com> wrote:
>
>> On 2020-07-07 05:04, joe mcguckin wrote:
>>> Theoretically, Starlink should be faster cross country than
>> terrestrial
>>> fiber.
>>>
>>>
>>> Joe McGuckin
>>> ViaNet Communications
>>>
>>> joe@via.net
>>> 650-207-0372 cell
>>> 650-213-1302 office
>>> 650-969-2124 fax
>>
>> When there is no clouds.

In my experience, all that ACM has achieved is that when link becomes
"slow" and if it rains outside, it means that it will be down completely
after few seconds.
Previously with CCM or DVB-S without 2, it simply disappear without
warning.
And yes, I have and cheap and expensive Microwaves >10Ghz too.
ACM/VCM really helps if you want to live on the edge, milking each db,
(edge of link budget, e.g. small antenna size, interference), and this
is actually very important to increase profitability, especially in case
of multipoint VSAT, but it is near useless against rain fade.