Arnie M
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It worries me a bit if police say they can place CB phone "at" the Ocean Club.
IMO the data harvested in May 2007 locates phones only by the name of the mast, which yields a huge area such as "in or near PdL"
Triangulation expert evidence between the 3 masts using the azimuth (Angle of Arrival) and Time Difference of Arrival (TDOA) might get him very close to OC but I think they must have GPS (or WiFi connection as suggested).
But look at the many thousands of phone data which the Met experts used to track the 6 phones of the "doctors group". The data gives mast name only. There is not a single example of AoA or TDoA or phoneGPS being used in that analysis.
Yes.
But I think you are correct that it all comes down to what data was available from the tower logs in the first place.
My experience on other cases is the kind of data you could get say 10 years ago, is much less than today, and also there are limiting factors in what data is stored in the medium term.
So if you show up with a warrant a year later for a particular number, then it may no longer be possible to get more detailed data for example - this happened on the McStay case. All that was left was the specific data connections - e.g. inbound call.
This is frustrating, but of course LE cannot harvest all the data of all citizens whenever they want.
Phone tracking ..... I will try to explain it as simple as possible ..... years ago I did a detailed explanation on a different case , complete with pictures and diagrams , but I dont feel like looking it up again.
When you make a call it uses a high tech encrypted signal between you and the person you are speaking to .... and that signal has absolutely nothing to do with phone tracking .... nor is it recorded or preserved .
However every phone constantly emits "pings" .... a low tech analog type signal broadcast in all directions sending out feelers for towers and your physical phone in your pocket always knows where it is in relation to all the towers it is locating .... (unless you turn your phone completely off ) ... that way your phone knows which tower is closest with the strongest signal if you decide to make a call.
And if you are moving or driving this simple signal system continues to monitor surrounding towers so it can hand you over to a stronger signal as you approach it.
Each cell phone tower antenna (mast) has an array of up to 6 rectangular panels in a circle facing all directions .... but your phone only locks on to the one directly facing you (your phone) .... as you move one panel will hand you over to the next etc.
All of these low tech signals are recorded .... they take very little storage space and are often kept for a long time or forever ..... most importantly is that is how the phone company determines where calls are placed from and what type of long distance charges may apply .
Mainly phone companies like to sell the information to marketing and advertising companies .... no private information is revealed ... it is more like .... we have a thousand people (phones) from a certain area of a city stopping at a certain shopping center so marketing companies know the best places to spend advertising dollars.
Police can only access those records with a warrant ... and they can tell the direction , speed (elapsed time) between locations and if more than 2 towers are being pinged pinpoint location down fairly accurately. It is simple old school triangulation used by navigators for hundreds of years ... instead of looking at the horizon and a couple of stars through a sextant like the old ships did .... your phone looks at towers. Very simple.
In the MM case if the parents and group of friends remained at the resort it would just use the local tower of course ... and if CB was in the area it would indicate the same tower ..... but if he was driving around that information should be there also ... and typically police remain tight lipped about everything they know. Unless CB was smart enough to turn his phone completely off ... there should be a record of which direction he went the evening MM disappeared.
And that would be most interesting