When you dial 9-1-1 from a cellular phone...

• The call may be answered in a different town or county.  Radio signals do not always travel the most direct route and may "bounce" out of your local area.
• If your call is disconnected, the dispatcher may not be able to call you back.
• You must carefully describe your location.  If you don't know the exact address, use prominent landmarks - buildings or features that most people will recognize.

Today, the technical requirements of an effective and efficient 9-1-1 system are directly tied to the dynamic world of telecommunications.  The growth of wireless telephone service alone has taken priority in the daily operations and planning of future 9-1-1 requirements.  It's estimated that 45% of the population in Texas have a cellular phone (2002).  About 50% of all 9-1-1 calls in Ector County originate from a wireless telephone.

The use of cellular and PCS (we use the generic term wireless) phones has attracted the attention of lawmakers and in July 1996, the Federal Communications Commission issued Report and Order 94-102  calling for the accommodation of wireless 9-1-1 calls.  In affect, the "enhanced" features of  9-1-1 are to be available to those users just as they are to wire line telephone users.

The basic components of Enhanced 9-1-1 are Automatic Number Identification (ANI) and Automatic Location Information (ALI) and the FCC report calls for these components to be implemented for wireless service in two phases.

Phase I

By April 1998 wireless providers are required to furnish the information necessary for Automatic Number Identification (ANI) for 9-1-1 calls.

ANI is more difficult to furnish to wireless callers because wireless telephone numbers must include all ten digits (the area code + telephone number).  A cellular phone user can roam about the entire country with their phone number so it cannot be assumed that when they dial 9-1-1 in Ector County they are calling from a telephone number with a local area code.  Unfortunately, the existing telephone switching equipment in Ector County does not allow the use of ten-digit telephone numbers for selecting the route of wireless calls.  A plan is underway by telephone companies throughout the state to replace this older switching equipment but it is a time-consuming and expensive project.  We are also considering interim solutions for Phase I and, ultimately, 9-1-1 service fees will be needed to help pay for these upgrades.

Phase II

By the end of 2003, wireless providers will be required to furnish the information necessary for Automatic Location Information (ALI) for 9-1-1 calls.  The location will be identified by coordinates that place the caller's location "within 400 feet, at least 67% of the time".  NOTE - SOME WIRELESS CARRIERS WILL REQUIRE THEIR SUBSCRIBERS USE A NEW GPS-ENABLED TELEPHONE BEFORE THE CALLER CAN BE LOCATED.  CHECK WITH YOUR CARRIER TO MAKE SURE YOU HAVE THE APPROPRIATE TELEPHONE HANDSET.

Because of their very nature, wireless callers do not have a permanent location or address.  ALI information is a challenge because location technology must be developed and implemented to allow public safety dispatchers to identify the caller's location.   The location of a wireless caller may be identified by computers comparing the difference in time of arrival of the wireless signal between two or more receiving antennae.  The use of GPS is another alternative method for locating wireless callers but GPS would require the replacement or retro-fitting of all existing wireless telephones.  Several technologies are being tested but many technical and budget problems remain.
 
 
 

FCC REQUIRES WIRELESS CARRIERS TO FORWARD ALL 911 CALLS (FCC DOCKET 94-102)

In December, 1997 the FCC ruled that all wireless carriers are required to transmit all 911 calls regardless of whether the calls are placed by the carriers' subscribers.  In other words, if you subscribe to cellular service with Cellular Company One but you are travelling in an area covered by Cellular Company Two, Company Two may not be required to pass your phone calls to other telephone numbers but they must pass your calls if you dial 9-1-1.  This also means that if you have a working cellular telephone but do not subscribe to cellular telephone service with any cellular carrier, you can still use 9-1-1 (barring technical incompatibility).