[time-nuts] - LightSquared is back now called Ligado

[bill]

Hi,
This is going to affect INMARSAT and Iridium satellite phone service as 
well.  Does anyone know anything about this?

As I see it, putting such transmitters into operation will render 
consumer grade GNSS receivers unusable.  High-end survey and
reference receiving systems might have to be upgraded with sharper 
filtering (much more costly and bulky) to maintain reliability.
If Ligado transmitter spurious emission requirements at band edge will 
have to meet unrealistic requirements to prevent interference
with GNSS.  L-band satphone service could be completely cooked.

I guess the FCC suffers from being co-opted by the current crop of 
kleptocrats and incompetents that affect other branches of government as 
well..and not just in the USA!
Cheers,
Bill


On 18.04.20 11:37, Dave B via time-nuts wrote:
> Hi.
>
> Reading that web page, they are talking dBW levels, not dBm levels.
> Hopefully that is a typo, as 0dBW is of course 1000 times more than 0dBm.
>
>
> To quote from the page:-
>
> The base-station power reduction is "from 32dBW to 9.8dBW," and Ligado
> committed to a 23MHz "guard-band using its own licensed spectrum to
> further separate its terrestrial base station transmissions from
> neighboring operation," the FCC said.
>
> 32dBW if I'm not mistaken, is some 1500W !   9.8dBW is just under 10W.
> (Maybe someone costed the potential electric bill per site?)
>
>
> dBW is a common spec' in licensing forms, certainly over hear.
>
> Even so, 9.8dBW from a femtocell (like a plug in wall wart sized thing)
> is going to really anger the tinfoil hat brigade.
>
>
> But anyway, what the hell is the point of a satellite based system, if
> you're going to pollute the downlink frequencies.  Even more so, when
> said satellite reception systems are working with signal levels close to
> the ambient noise anyway.
>
> That, and isn't 5G intended for (among other things) mobile devices?
> That probably will be trying to use GPS etc as well.   Shoot in own foot
> time I think.
>
>
> Regards.
>
> Dave B.
>
>
>
> On 18/04/2020 00:56, time-nuts-request at lists.febo.com wrote:
>> Message: 1
>> Date: Fri, 17 Apr 2020 13:37:26 -0400
>> From: Scott McGrath <scmcgrath at gmail.com>
>> To: time-nuts at lists.febo.com
>> Cc: Mike Rogers <mike at mrogers.org>
>> Subject: [time-nuts] LightSquared is back now called Ligado
>> Message-ID: <1840EAFF-B006-4512-8DA3-F7C1463B8370 at gmail.com>
>> Content-Type: text/plain;	charset=us-ascii
>>
>> Supposedly lowering Tx power on terrestrial network from +23 DBm to +9.8 DBm will make everything better.  Ajit Pai is listening only to carriers and ignoring DoD who is stating it will significantly degrade and/or make useless the GPS system.
>>
>>   Not to mention ADS-B which was installed at great expense by the private and commercial aviation systems. And is totally dependent on the GPS segments most affected by Ligado
>>
>> Read and weep
>>
>> https://arstechnica.com/tech-policy/2020/04/fcc-to-approve-5g-network-despite-military-saying-it-will-harm-gps/