Can You Find Me Now? E911 & VoLTE

July 11, 2016

emergencyOver 240 million 911 calls are made in the US each year. Before an emergency responder can help a caller, she must know where the caller is. This was relatively easy when people called 911 from fixed phones. But not today, when over 70% of 911 calls are made from mobile phones.

Going Mobile – Rules for Wireless 911

The FCC recognized the “can you find me now?” problem for wireless 911 in mid-90s, and issued wireless 911 rules that apply to operators with licensed spectrum:

  • Basic 911: Allow all 911 calls, even if the caller is not a subscriber
  • Phase I Enhanced 911 (E911): Provide PSAP with caller’s telephone number and location of base station used
  • Phase II E911: Provide PSAP with caller’s location, accurate within 50m to 300m based on location technology used

Operators could either use handset based location technology (i.e. GPS) or network based location technology to meet Phase II E911 requirements. When using a network based solution, they had to provide 100m accuracy for 67% of the calls, and 300m for 95% of the calls. When using handset based solutions, they had to provide 50m accuracy for 67% of the calls, and 150m for 95% of the calls.

New Rules – for the Great Indoors

Today, over 70% of mobile calls originate inside buildings. Neither GPS nor network-based location techniques optimized for the macro network work well inside buildings. So, if you make an emergency call from a building, you may be out of luck.

In February 2015, the United States FCC issued its “Wireless E911 Location Accuracy Requirements – Fourth Report and Order” that asks major wireless services providers to provide (1)dispatchable location or (2) x/y location within 50 meters within the following time frames:

  • By 29 Jan 2017: 40% of all wireless 911 calls
  • By 29 Jan 2018: 50% of all wireless 911 calls
  • By 29 Jan 2020: 70% of all wireless 911 calls
  • By 29 Jan 2021: 80% of all wireless 911 calls

The FCC R&O has additional requirements on vertical location (“z-coordinate”) as well for cases where a dispatchable location is not available. The end goal of these requirements is to ensure that the person receiving emergency assistance receives timely help, and service providers should “view these requirements as a floor, not a ceiling”.

Meeting Indoor E911 requirements – with SpiderCloud

SpiderCloud’s E-RAN platform can help operators deliver dispatchable location for E911 calls today. Further, there are no handset dependencies, thus any VoLTE handset can place an E911 call to the PSAP servicing the call, and be located.

How is this done?

  • Every Radio Node is its own radiating element, and is provisioned as an individual ECGI with dispatchable location information of building, floor, and zone attached to it.
  • The PSAP receiving an E911 call queries a database to convert the ECGI to the dispatchable location.
  • Assuming a typical cell spacing of 100 feet, the First Responders are well inside the 50 meters (164 feet) FCC requirements.

SpiderCloud’s scalable Small Cells add unique and cost effective native capabilities to the E911 Public Safety environment for indoors where GPS does not function and alternative solutions can’t cost effectively add E911 to comply with FCC resolution demands. There is no need to rely on handsets in the x/y/z location determination process as dispatchable location is solely a network based function. And, most important, since each SpiderCloud small cell covers a relatively small area, the associated dispatchable location is more precise, and improves the speed at which an emergency responder can find the caller.

Safety Matters – and not just because the FCC demands it

Meeting E911 requirements helps operators differentiate their services from over-the-top (OTT) providers. The day is not far when Apple or Samsung give handset owners the option of picking the default dialer on their handsets. Subscribers could still continue to use Verizon or AT&T, or they could pick Whatsapp, Google Voice, or Facetime. Wireless service providers would need to offer a differentiated services package. Reliable 911 – outdoor and indoor – could be a key part of their offering.

– Art King, Director of Enterprise Services & Technologies
Twitter: @ArtKingg
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– Amit Jain, Vice President of Marketing & Product Management

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