[VoiceOps] Ray Baum's act and all-softphone deployments

[Jay Hennigan]

On 9/27/21 13:34, Mark Lindsey via VoiceOps wrote:
> In the top 25 cellular market areas, nationwide cell phone providers are 
> already required to provide Z-axis (elevation) data within 3 meters for 
> 80% of calls [for compatible devices].  The requirements increase each 
> year; by 2026, /all/ cellular providers are required to provide z-axis 
> precision for dispatchable location of +/- 3 meters everywhere in the US.
> 
> This is all in addition to providing +/- 50 meter horizontal (x, y axis, 
> also known as latitude and longitude) precision for 911 calls.

Interesting as elevation accuracy for GPS is worse than lat/long.

So when first responders get dispatched to 34.2270545 degrees north, 
117.6422397 degrees west, 538 meters AMSL, where do they go? (I just 
randomly typed those numbers so if it's under a mountain don't blame me.)

Considering just the x/y axis, determining the right room or suite in a 
large single-story office building, factory or warehouse is going to be 
a challenge. In a huge multi-story high-rise with poor to no internal 
GPS reception it's going to be nearly impossible. Especially if it's in 
the middle of a bunch of other high-rise buildings with corresponding 
multipath and reflections.

-- 
Jay Hennigan - jay at west.net
Network Engineering - CCIE #7880
503 897-8550 - WB6RDV