I'm unconvinced Clarke's Law is operative here.
A more appropriate model is the Swiss Army Knife... a single tool to be
all things to all people. In reality, such a tool or program does nothing
very well. Examples abound.
YMMV,
-John
=
Any competent engineer could have
Any competent engineer could have told the powers that be that a satellite
system based in LEO has a relatively high risk profile from the
Universe/hostile activity/spoofing and jamming
Yes GPS is/was oversold.
Trouble is Clarkes law applies here (any sufficiently advanced technology is
Exactly what do you mean by ... based in LEO has a relatively high risk
profile from the Universe/hostile activity/spoofing and jamming...?
Other than a LOS, in a jammers immediate area, GPS is not subject to
jamming, and for the critical users, ie, the DOD, very difficult to jam,
even in a LOS.
I think the largest concern about jamming is for civilian uses, rather
than military, mainly because military receivers are designed and built to
be more immune. Also, military systems are far more likely to have good
grade INS.
Furthermore, there are probably a couple of orders of magnitude more
Satnav are not LEO but MEO. Which is good - less sv to cover the earth. Less
good because distance is higher compared to LEO regarding signal power at earth.
--
Björn
Skickat från min Mobil
Originalmeddelande
Från: Scott McGrath scmcgr...@gmail.com
Datum: 2013-07-30
It is easy to jam a simple GPS receiver. Harder to jam a military
receiver. In a conflict a jammer of any kind is pretty much a beacon that
says here I am. It is one of the bigger problems of jamming, you have to
radiate RF. So either you have to be very close to your target or have a
The atmosphere protects the earth from a lot of stuff the universe throws at us
Solar flares , space junk , micrometeors just the usual hazards the space at
large has. Inability to service satellites when transmitters or RCS fuel
exhausted
Sent from my iPhone
On Jul 30, 2013, at 9:31 AM,
If you read article the City of London basically has a GPS denial 10-15 minutes
daily this covers a couple square miles
A lot of people are under the misconception that the spy shop jammers only do a
few feet. Reality is most of them are 100-500 mw and blank out at least a
square mile
A
What does that have to do with ... based in LEO has a relatively high
risk profile from the Universe/hostile activity/spoofing and jamming...?
I note the previous correction to your statement, that it is MEO not LEO.
Lester B Veenstra MØYCM K1YCM W8YCM
les...@veenstras.com
US Postal
Yes. LOS jamming of the civilian code is easy; However whey do you think the
use of LEO aids this?
Any competent engineer could have told the powers that be that a
satellite system based in LEO has a relatively high risk profile from
the Universe/hostile activity/spoofing and jamming
It doesn'tIt simply increases the risk that GPS will be made unavailable
due to events outside the operators controlHence system risk profile is
high
Was not so high when LORAN was available as aviation, maritime and timing
applications could gracefully degrade to LORAN in the
Well which is it:?
Question: LOS jamming of the civilian code is easy; However why do you think
the use of LEO [MEO] aids this?
Your response: It doesn't
Then you state:It [ from context, the use of MEO orbit] simply increases
the risk that GPS will be made unavailable due to events
Don't junk your ADF just yet.
On 07/30/2013 11:46 AM, Scott McGrath wrote:
It doesn'tIt simply increases the risk that GPS will be made unavailable
due to events outside the operators controlHence system risk profile is high
Was not so high when LORAN was available as aviation,
Hi
A sector antenna autocorrelateor should be a pretty useful gizmo for tracking
GPS jammers. You have most of the gear already in a cell site. Software patch
and away you go. Of course you would need pretty good timing, but that's not
impossible ….
Bob
On Jul 30, 2013, at 7:27 PM, Chuck
Group,
Has anyone used IEEE 1588 to synchronize clocks on an Ethernet network?
I was involved in the design of time sync for Foundation Fieldbus circa
2000.
We needed one millisecond accuracy, so we went with SNTP on local
networks.
I've just seen an ad for a switch that can do 1588, and looked
The only switch I know that supports IEEE 1588 is the Cisco CGS 2520 and it was
about 10 k before discount. It's intended for use in smart grid applications
NICs are about 500 each from a variety of vendors. Altera makes most of the
silicon
Sent from my iPhone
On Jul 31, 2013, at 12:19 AM,
16 matches
Mail list logo
