What are the limitations of determining a 5G smart phone's location?

[dlgoff]

TL;DR Summary

What is the radius around smart phone location

I'm curious about what the radius around where a 5G smart phone location would be.

 

[anorlunda]

Can you rephrase the question? I'm not sure what radius you're asking about.

 

[dlgoff]

Can you rephrase the question? I'm not sure what radius you're asking about.

I'm asking, if you put a 5G smart phone on the ground, and drew a circle around it where it's laying. Can it be tracked? And if so, what would that radius be?

 

[anorlunda]

It will be pinging the nearest cell tower. That places you within the radius of the tower's range. That's the same for 2G, 3G, 4G, and 5G or any cellular technology. 5G should be no different.

Otherwise, I'm totally not understanding your question.

 

[dlgoff]

It will be pinging the nearest cell tower. That places you within the radius of the tower's range. That's the same for 2G, 3G, 4G, and 5G or any cellular technology. 5G should be no different.

Otherwise, I'm totally not understanding your question.

I guess what I'm really wanting to know is, if I'm carrying a smart phone, how closely can I be found. From my location, there should be a circle around me where I can be found. What would that radius be?

 

[berkeman]

I'm asking, if you put a 5G smart phone on the ground, and drew a circle around it where it's laying. Can it be tracked? And if so, what would that radius be?

Does it have its GPS location feature enabled?

Or are you asking what is the tower-only location resolution and accuracy compared to 4G?

 

[dlgoff]

Does it have its GPS location feature enabled?

Assuming it does and it's enabled, How close to where the phone is can it be found. BTW I don't have a smart phone. I am just curious about how close I could be found; say I was lost somewhere. i.e from my position, there should be some circle around me where the phone could be found.

 

[berkeman]

Assuming it does and it's enabled, How close to where the phone is can it be found. BTW I don't have a smart phone. I am just curious about how close I could be found; say I was lost somewhere.

It looks like it's pretty good. The GPS accuracy will be independent of 5G or 4G, etc.

 

[berkeman]

BTW, if you are lost and cell phone battery consumption is a concern, only enable the GPS location feature long enough to get your coordinates (like from Google Maps), then go back to tower-only location feature to save on battery life. Then text your position to 911 (if that feature is enabled in the area where you are), or text it to somebody you know who can relay the information to searcher via the 911 phone network.

 

[dlgoff]

It looks like it's pretty good. The GPS accuracy will be independent of 5G or 4G, etc.

View attachment 295708

Okay. Thanks berkeman. That's exactly what I was looking for. 16 feet.

 

[dlgoff]

@berkeman
BTW, I saved that image from GPS.gov

 

[Borek]

Actually if you have GPS switched off you can be still located using information from cell towers, but the shape of the area won't be circle, more like some kind of a polygon, as in Voronoi diagram.

5G has a very short range, something like 1000 or 1500 feet, that should put an upper limit on the Voronoi cell size.

 

[sysprog]

If it's cell tower proximity only, using comparison of signal strengths between two or more towers, along with triangulation, it's not nearly as accurate as GPS, but in an urban are with high density of cell towers, it can get within a block or so. Here's a 911-oriented FCC white paper on various methods of locating a phone:

 

[Melbourne Guy]

There is another potential location method, @dlgoff, and that is via in-range WiFi networks. Maps have been developed based on SSIDs picked up by the phone and enriched with the associated GPS coords. Add enough of these data points and sites such as https://wigle.net/ can provide location to within 20m. Android as least has been harvesting this telemetry for years!

 

[sysprog]

From the FCC white paper linked in post #13:

Wi-Fi-based positioning system (WPS) or WiPS/WFPS is used where GPS is inadequate due to various causes including multipath and signal blockage indoors. Wi-Fi positioning takes advantage of the rapid growth of wireless access points in urban areas. The Wi-Fi hotspot database gets filled by correlating mobile device GPS location data with Wi-Fi hotspot MAC addresses. The possible signal fluctuations that may occur between the phone and the access point can increase errors and inaccuracies in the path of the user. Additionally, in a power outage scenario, W-Fi detection may not be possible.​

 

[artis]

IIRC in theory as the radio frequency increases the resolution of the "spot" you want to triangulate increases so you should be able to have better accuracy at determining your location.
But I suspect that 5G will only be in urban areas since it's usable radius is lower than 4G and you won't probably put a cell tower after every 10th tree in a forest.

 

[Oldman too]

BTW, if you are lost and cell phone battery consumption is a concern, only enable the GPS location feature long enough to get your coordinates (like from Google Maps), then go back to tower-only location feature to save on battery life. Then text your position to 911 (if that feature is enabled in the area where you are), or text it to somebody you know who can relay the information to searcher via the 911 phone network.

When it comes to low batteries, this will be a cool feature. a real bonus. (Sorry, hope I'm not straying from the topic)

https://www.nature.com/articles/s41598-020-79500-x

https://rh.gatech.edu/news/645735/leveraging-5g-network-wirelessly-power-iot-devices

 

[Dullard]

Interestingly (perhaps):

Both GPS and cel tower 'triangulation' are weak on the 'elevation' part of determining a location. In both cases, the geometry is the problem - best geometric precision is obtained when the satellites (or towers) are at opposite ends of the axis of interest. That's tough for elevation.