Problem with use of GPS or similar giving Police a wrong fix.

[oldestguy]

I';m a civil engineer but also a Ham operator, but know nothing about using GPS (our surveyors use it I think). In the past three months the Police here stop in because they are getting a false alarm at our address (three times now). Our single cell phone is not turned on, but uses a local area code, while the offending phone is a nearby area code. I suspect that somehow the various towers receive the same signal from a given distance and the several towers then come up with where the signal circles cross. Could not those crossing areas be far from me also? So any advice for the local cops? Nice guys, but it wastes their time to come in and visit.

 

[GregLocock]

GPS is satellite based and rather hard to spoof. They must be using a location system based on cell phone towers. There are good reasons for that, many people do not run GPS on their phones as it wastes power.

Cheers

Greg Locock


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[MikeHalloran]

Phones today also use wifi hotspots for positioning.

Mike Halloran
Pembroke Pines, FL, USA

 

[IRstuff]

Seems silly to me that the police don't check to see what the billing address is for the false alarm.

Most older alarms are tied to landlines, and thence a physical address. Cellular systems are not so, and they must broadcast an address that is likely a manual entry, and subject to typos and errors.



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[VEBill]

A couple of years ago, there was a news item about a poor traumatized household that happened to reside at somebody's default center of the USA. Due to inept system design and programming, any 911 calls where the initial or default location was only as precise as "USA" were somehow defaulted to the same latitude and longitude, which was then translated into their address.

The solution, which took forever to implement, was that the inept company adjusted their default latitude and longitude to be in the middle of a nearby lake.

Just an example of the design fragility of the 911 system.

Such issues can be dangerous, as sometimes the 911 call is about something seemingly requiring an armed response. Done intentionally it's called 'Swatting' and has resulted in serious incidents. So it's not something to be taken lightly.

If it continues, it might call for legal action against your local 911 call center, if such is needed to capture the attention of their management. They're probably the only ones in a position to investigate and correct. They should do so willingly and proactively, or be legally encouraged to do so.

Good luck.

 

[IRstuff]

One other point about location services; my company routes EVERYTHING through their central corporate data processing center, which is half the country away from where I physically reside.

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[DanEE]

It might be worth contacting the Emergency Operations Center Director responsible for the 911 call center covering your area as this is in part a call center/dispatcher protocol/training issue. I'm also a ham, with our ham club being affiliated with and meets in our local EOC facility. It ought to be in their dispatcher training protocol for them to be cross checking the location with the caller, rather than relying solely on cell phone location data, as these type errors can be quite common. I've seen the call protocol for the dispatchers at our EOC and it puts a lot of emphasis on this. Concur with VE1BLL comments, this is neglience on their part in training and call protocol; if you don't get adequate response with the EOC, document these incidents, and escalate the issue.

Depending on how modern their call center dispatcher software is, they could possibly flag the phone numbers and address in question that there is a problem with cell phone location errors frequently pointing to your address. I have a scanner for the trunked radio system in our area, and it is quite common for officers enroute on the call to ask dispatch about the call history for that phone number/location.

Many modern call centers have GIS data integrated in so dispatchers confirm and give detailed location data to officers, fire or EMTs while enroute. It's not uncommon for the dispatcher to relay easily visible landmarks, color/type vehicles parked in the vicinity, info obtained from the caller, and passed on to the responders to verify upon approach.

If nothing else works, get public attention on the matter; if there is a local TV station that does "troubleshooter" type reports, call the TV station every time this happens. Public humulation works in many cases where nothing else will.