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* * *

"I've got something for you." The man making the phone call identified himself to Daphne as Frederick Osbourne of AirTyme Cellular. He continued, "A lieutenant named Boldt left both his and your names in case I had anything, and I'm only getting Boldt's voice mail."

   Information concerning Flek's cellular phone, she realized, her heart leaping in her chest. She and Boldt had discussed Osbourne. "Yes," was all she could think to say.

   "It's not real-time. He and I went over that. I'm sorry about that. We're working on it; we have some good ideas, actually, how we might improve that. I explained the various technologies and their limits to the lieutenant when we spoke. But I think you'll find it interesting. Would you like to come over to the offices?"

   "It's seven o'clock," Daphne pointed out. "If you have a location for the suspect, perhaps you could just give it to me over the phone," she suggested.

   "Not exactly a location," he answered. "More like a theory. I think it better explained in person. Can you get hold of Lieutenant Boldt?"

   "I can try. Yes."

   "You'll want to see this before eight o'clock . . . at least before eight-thirty. Sorry I've called so late, but I only put it all together just now. By eight-thirty you'll have lost him."

   "Lost him," Daphne repeated, her mind whirring as she realized Osbourne believed he had found him. "I'll be right there."

* * *

Liz knocked on the door to her husband's study, waited a moment and then let herself inside. Krishevski occupied the throne of the recliner while her husband sat in a chair facing him like a child in the principal's office. She paused, looked her husband in the eye, and said, "Phone call for you."

   "No calls right now," he reminded her politely.

   "It's her," she said. "Says it's 'important.'" She drew the quotation marks in the air.

   "I'll have to call her back."

   "I'll tell her," Liz said. She seemed to take pleasure in it. She pulled the door shut, wondering why the music was playing so loudly and what it was meant to cover.

* * *

The AirTyme Cellular Regional Control Center—"RCsquared," Osbourne called it—occupied portions of the twenty-first and twenty-second floors of the Columbia Center skyscraper. Normally such real estate would have commanded quite the water view, but RC-squared was a blacked-out control room that stepped down in tiers to a curving wall of projection screens mapping cellular phone traffic over a seven-state area that included portions of Utah, Nevada, and northern California. It looked like something from Mission Control. Daphne counted seventeen people at computers, all wearing telephone headsets. The room was alive with hushed, indistinguishable voices.

   "Wow," Daphne said, sensing that Osbourne expected some kind of reaction.

   He checked his wristwatch. "We're pressed for time. I wanted to show you what I've come up with. So, if you'd direct your attention to the last screen on the right, Lieutenant Matthews.

   "As I'm sure you're aware," he continued, "the U.S. Congress passed a bill requiring us to geographically locate nine-one-one calls placed from cellular telephones, which presented us with a serious task in terms of the older generation analog phones. The new generation digital phones have GPS chips—Global Positioning Systems—inherent in their technology. But the older analog models without the chips have only their signal.

   "There are several ways to attempt to locate an an

alog cellular phone that's in use, and probably a half dozen companies competing for the best methodology," he continued. "All of these methods were derived from the military. The two most common are DF, direction finding, and TDOA, time difference of arrival. Both are variations on something called triangulation. We use a company out of Canada that has taken TDOA one step further into something called hyperbolic trilateralization. Triangulation and trilateralization work off the same principle: If you have three antennas, all receiving a radio signal from the same source, and you can measure and record the time that a source radio signal arrives at each of those antennas, then you can plot the location of that original source signal. A cell phone signal lights up several towers at a time, sometimes as many as a half dozen or more. These towers pass reception and transmission one to the other in what's called a hand-off, as they determine which is the closer or more optimal tower. Because trilateralization works at very high speeds, constantly measuring the time to base, as we call it, its method of triangulation is far more accurate than many of its competitors. You with me so far?"

   "I think so."

   "The long and the short of it is, the older method of triangulation could take several minutes or even hours to process accurately. This newer method I'm talking about is a real-time system with pinpoint accuracy because it's measuring a cell phone transmission in nanoseconds and plotting the location accordingly. Your problem is this," he stated. "Full government compliance is not mandated for another eighteen months. AirTyme has the hyperbolic trilateralization software and, of course, our firmware network of towers and transmission centers, but the two are not yet fully married. Adding to our difficulty—two of the three towers we may be using to measure time to base may belong to one or more competitors. They will gladly provide us the TDOA data, but it takes time to arrange. We estimate full network compatibility in ten months."

   "You're losing me," she admitted. "You do, or do not have a way to locate that cell phone number Lieutenant Boldt gave you?"

   "With the help of our competitors, we can run the software on data previously gathered. In terms of your needs that means we can . . . if you envision it as laying the TDOA software on top of information we've already collected . . . the software then analyzes that data and spits out a location for us, though that data is typically hours old because we've had to gather it elsewhere." He saw her disappointment register. "The only other technology available to us—log-on signals—is real-time, but allows no location accuracy whatsoever. To my knowledge no one's come up with anything for log-ons. But that's one of the areas we're looking into for you."

   "You said I might miss him," Daphne reminded, looking at her own watch, "which implied you had found him, or did I misinterpret?"

   Osbourne reached forward and tapped the man in front of him on the shoulder. The computer technician danced his fingers across the keyboard. Until that moment, Daphne had not realized this person was a part of their discussion. Osbourne said, "Eyes on the screen to the right."

   The screen was enormous, perhaps a hundred square feet, half the size of a small movie theater screen. On it appeared a color map of the city that Daphne clearly recognized. The dark green to the left she took to be Puget Sound.

   Osbourne said, "If the person you're interested in had been calling on a newer phone, our GPS technology would have done the work for us. The only shortcoming of GPS is line-of-sight interference, which TDOA gets around, and therefore ends up complementing the technology perfectly. But your suspect is calling out on an older model analog, I'm afraid. Each time he placed a call in the last eighteen hours, our network, and our competitors' networks, recorded those signal transmissions, for his and hundreds of thousands of other phones, all concurrently, twentyfour/seven. A tower receives his signal, and the computers time-stamp that arrival for the sake of billing records. Downtown, his transmission signal might light up six or eight towers, all at fractions-of-a-second differences. We have a record of all of that." He tapped the man's shoulder again. "What you see next are the various transmission locations of calls he has made. A red dot means he was standing still. A red line means he was moving. We shade that line pink to burgundy, to indicate direction—pink being the area of origin, burgundy, termination."