Now the company that created the technology and licenses it to Cingular Wireless, AT&T Wireless and VoiceStream Wireless is launching its final two-month test that will likely decide the future of the technology, executives say.
"The pressure is really on," said Chris Wade, chief executive of Cambridge Positioning Systems, which created the (EOTD) Enhanced Observed Time Difference technology. "We're focusing large parts of our company on this effort."
All U.S. carriers are trying to meet a 1996 federal mandate to be able to locate cell phones dialing 9-1-1 within 100 yards. While satellite-based systems have proven easier to adapt to the standard, the land-based EOTD system suffers in rural areas because of a lack of base stations to locate a call.
EOTD uses up to four different cellular base stations to figure a cell phone's location, measuring the arrival times of the call at various different cellular antennas. But in rural areas, cellular base stations are sometimes miles apart. Instead of four, it's likely there will be just two base stations to help figure out the location, making it less accurate, Wade said.
"This is not developing an IP router or a new kind of modem," he said. "This was brand new, completely unthought-of-before technology that takes a long time."
The technology has beaten the standards in urban tests, Wade said.
The three carriers using EOTD have already told the Federal Communications Commission they will miss an upcoming June deadline because of problems companies are having in making EOTD network equipment and handsets. Cingular Wireless told the FCC it would abandon EOTD in 2003 if it still doesn't have working equipment.
The upcoming tests will be conducted on Cingular's network equipment in San Francisco, AT&T Wireless's networks in Dallas and Portland, and VoiceStream equipment in Washington, Rhode Island and Texas, Wade said. The technology has to locate two-thirds of 911 calls within 100 yards, the federal mandate for E911 accuracy.
"Yes, sure, we are behind schedule; we are delayed," Wade said. "The real answer is no technology is really good enough. You are going to get areas in which you are very good and stunningly accurate, and you'll get some areas that are absolutely horrible."
The FCC is considering requests for a delay from the three carriers to work out the EOTD issues. The FCC has generally granted most delay requests, the last coming in October when the FCC let all U.S. carriers miss a deadline to begin building their E911 networks.
While most got off with a waiver, the FCC proposed fining AT&T Wireless $2.1 million, a fine AT&T Wireless has promised to fight. Cingular Wireless has agreed to make a "voluntary contribution" of $100,000 to FCC regulators.