Re: Story of missing hiker in Joshua Tree NP
Posted: Wed Nov 24, 2021 11:55 am
Thanks Richard. Here's the source discussing cell phone distance determination (Other Hands). See page 3.
https://www.otherhand.org/wp-content/uploads/2012/04/Ewasko-ping-discussion.pdf
Is there newer information indicating Bill's phone used a different distance determination? I've seen in various places that multiple methods are possible, though most require more than one tower, or GPS on the phone. I'm not a cell phone expert, though I've worked in technical fields and know that seemingly simple answers (like cell phone distance) are rarely simple in practice. Conversely, some simple appearing things are simple and very accurate.
I lean in the direction of the early SAR folks who dismissed the distance as unreliable (and searched primarily outside the 10.6 miles). Especially with a single ping far from the tower in rough terrain. I take the ping clue as Sunday morning Bill's phone was almost certainly on and made contact with Serin tower, maybe from 10 miles or so.
https://www.otherhand.org/wp-content/uploads/2012/04/Ewasko-ping-discussion.pdf
I’m back into speculation mode here, but I think what the Verizon tech who examined the ping
did was to look at the RSSI levels and said, “That recorded tower signal strength corresponds to
a distance of 10.6 miles”. I then took that information and drew a 10.6 mile radius around the
tower’s location. But unless we were in flat Kansas, what I did was completely wrong.
Is there newer information indicating Bill's phone used a different distance determination? I've seen in various places that multiple methods are possible, though most require more than one tower, or GPS on the phone. I'm not a cell phone expert, though I've worked in technical fields and know that seemingly simple answers (like cell phone distance) are rarely simple in practice. Conversely, some simple appearing things are simple and very accurate.
I lean in the direction of the early SAR folks who dismissed the distance as unreliable (and searched primarily outside the 10.6 miles). Especially with a single ping far from the tower in rough terrain. I take the ping clue as Sunday morning Bill's phone was almost certainly on and made contact with Serin tower, maybe from 10 miles or so.