[aprssig] GPS possible disruption SE US Jan 20 - Feb 22

Thu Jan 20 13:27:46 EST 2011

NASA is one of the agencies that have entered into an agreement with the 
DoD on GPS testing...

Mike
WM4B

On Thu, Jan 20, 2011 at 1:00 PM, Gregg Wonderly wrote:

> On 1/20/2011 11:58 AM, Gregg Wonderly wrote:
>> What is the modulation of the GPS signal? Is it something that a 
>> larger power
>> transmitter could blanket an area and override the sats as in the FM 
>> capture
>> effect? I'd guess that "moving things around" could be a good reason 
>> for this
>> test. It implies that once a target is "guessed", that a high speed 
>> interceptor
>> could arrive overhead and direct GPS guided weapons away to somewhere 
>> else.
>>
>> I'd guess that smart weapons would be designed to "integrate over 
>> time"
>> correction of their trajectory and might not be vastly redirect-able 
>> at the last
>> minute. But dealing with wind changes and other things might make 
>> them much more
>> nimble and this could allow them to be "flown over" for a long amount 
>> of time
>> and directed to someplace else, completely.
>>
>> The recent noise about North Korea being ready to deliver long range 
>> nukes might
>> be a stimulus for this kind of activity.
>
> Also, given the location of this activity, it would not surprise me to 
> see an empty vehicle launched out of NASA out over the sea as a proof 
> of effectiveness if this is indeed what might be happening.
>
>> Gregg Wonderly
>> W5GGW
>>
>> On 1/20/2011 11:20 AM, mwbesemer at cox.net wrote:
>>> That is possible, and could probably be implemented via the WAAS 
>>> system, in
>>> areas that are augmented by WAAS.
>>>
>>> However, keep in mind that either jamming or offsetting GPS for 
>>> aviation or
>>> maritime customers would be relatively ineffective due to the fact 
>>> that those
>>> platforms are required to have redundancy in their navigation 
>>> systems via
>>> another source. (GPS backed by INS, DNS, Omega, LORAN, etc.) Also, 
>>> when near or
>>> over land, VORTACs are available for aircraft use (although they 
>>> could be shut
>>> off in case of emergency).
>>>
>>> Consider, however, the case of smart-munitions. Those that are 
>>> GPS-guided (are
>>> likely to) go into a fail-safe mode if GPS guidance was completly 
>>> disrupted
>>> (jammed). This mode might result in the self-destruction of the 
>>> weapon or in the
>>> safeing of the weapon (rendering it non-explosive, although you 
>>> still would not
>>> want it landing on your house).
>>>
>>> I'm only speculating on all of this (of course) but I did spend the 
>>> majority of
>>> the past 30 years doing RT&E/DT&E with the military. Most likely, we 
>>> will NOT
>>> hear anything specific regarding the results/purpose of this test 
>>> (unless
>>> Wikileaks gets a hold of it!) for the next 25 years or so. There are 
>>> some things
>>> that the public really doesn't need (or want) to know about.
>>>
>>> 73,
>>>
>>> Mike
>>> WM4B
>>>
>>>
>>>
>>>
>>> On Thu, Jan 20, 2011 at 12:03 PM, Lynn W. Deffenbaugh (Mr) wrote:
>>>
>>>> But with a jammer, the receiver knows they don't have a fix and 
>>>> something's
>>>> up. I'm more thinking an experimental scrambler/offsetter that 
>>>> allows GPS
>>>> receivers within the cone of influence to arrive at a solution 
>>>> based on the
>>>> received signals and generate fix, but they really aren't at the 
>>>> location the
>>>> fix describes. And the GPS consumer won't know that they're being 
>>>> mis-lead
>>>> (literally!).
>>>>
>>>> Lynn (D) - KJ4ERJ - Author of APRSISCE for Windows Mobile and Win32
>>>>
>>>> mwbesemer at cox.net wrote:
>>>>> Nope... you're thinking about it from the wrong angle.
>>>>>
>>>>> Ever heard of a GPS Jammer?
>>>>>
>>>>> Mike
>>>>> WM4B
>>>>>
>>>>>
>>>>> On Thu, Jan 20, 2011 at 11:36 AM, Gregg Wonderly wrote:
>>>>>
>>>>>> It sounds like a transmitter at 40,000ft that might be a "relay" 
>>>>>> of existing
>>>>>> GPS data. Perhaps they are trying to figure out how to make GPS 
>>>>>> work on the
>>>>>> ground in cities with tall buildings?
>>>>>>
>>>>>> Gregg
>>>>>> w5GGW
>>>>>>
>>>>>> On 1/20/2011 9:15 AM, Earl Needham wrote:
>>>>>>> I'm just wondering what they're doing that might disrupt GPS...
>>>>>>>
>>>>>>> Vy 7 3
>>>>>>> Earl
>>>>>>> KD5XB
>>>>>>>
>>>>>>> KD5XB -- Earl Needham http://groups.yahoo.com/group/cw_bugs 
>>>>>>> Quoting from
>>>>>>> the Coast Guard: ZUT Posted via Blackberry
>>>>>>>
>>>>>>> -----Original Message-----
>>>>>>> From: Steve Noskowicz<noskosteve at yahoo.com>
>>>>>>> Sender: aprssig-bounces at tapr.org
>>>>>>> Date: Thu, 20 Jan 2011 07:12:37
>>>>>>> To: TAPR APRS Mailing List<aprssig at tapr.org>
>>>>>>> Reply-To: TAPR APRS Mailing List<aprssig at tapr.org>
>>>>>>> Subject: Re: [aprssig] GPS possible disruption SE US Jan 20 - 
>>>>>>> Feb 22
>>>>>>>
>>>>>>>
>>>>>>> --- On Lynn W. Deffenbaugh (Mr) wrote:
>>>>>>>> ... I was looking for the coordinates that I could understand 
>>>>>>>> ...
>>>>>>>> Lynn (D) - KJ4ERJ -
>>>>>>>
>>>>>>> - - - - - -
>>>>>>>
>>>>>>> I often say that... "Can you explain that in terms I know?" (;-)
>>>>>>>
>>>>>>> 304906N = 30.4906 Deg North
>>>>>>>
>>>>>>> 0802811W = 80.2811 Deg West
>>>>>>>
>>>>>>> Google maps finds it A-OK.
>>>>>>>
>>>>>>> If you'd like it, I have an Excel spreadsheet that does 
>>>>>>> conversions between
>>>>>>> all forms of these. That is:
>>>>>>> 1 - Degrees.decimal (As shown above)
>>>>>>> 2 - Degrees, Minutes.decimal
>>>>>>> 3 - Degrees, Minutes, Seconds.decimal
>>>>>>>
>>>>>>> Contact via my web site or MYCALL at arrl.net
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> aprssig mailing list
>>>>>> aprssig at tapr.org
>>>>>> https://www.tapr.org/cgi-bin/mailman/listinfo/aprssig
>>>>>
>>>>> _______________________________________________
>>>>> aprssig mailing list
>>>>> aprssig at tapr.org
>>>>> https://www.tapr.org/cgi-bin/mailman/listinfo/aprssig
>>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> aprssig mailing list
>>>> aprssig at tapr.org
>>>> https://www.tapr.org/cgi-bin/mailman/listinfo/aprssig
>>>
>>> _______________________________________________
>>> aprssig mailing list
>>> aprssig at tapr.org
>>> https://www.tapr.org/cgi-bin/mailman/listinfo/aprssig
>>>
>>
>>
>> _______________________________________________
>> aprssig mailing list
>> aprssig at tapr.org
>> https://www.tapr.org/cgi-bin/mailman/listinfo/aprssig
>>
>
>
> _______________________________________________
> aprssig mailing list
> aprssig at tapr.org
> https://www.tapr.org/cgi-bin/mailman/listinfo/aprssig