Chapter 78. THEIR DIFFERENT DRUMMER pages 341 - 346
"My purse,’ she said, as they drove back to Bobby’s."
Chapter 78. THEIR DIFFERENT DRUMMER
Leaving the building in the hands of the "dustmen" and her purse behind, Hollis tells Garreth to stop the car when she sees emerge from a small car parked by the Phaeton, Inchmale and Heidi Hyde carrying a three-foot, gift-wrapped ax handle.
At a bar near the flat, Bigend tells Hollis that her purse is near Hastings and Main, "on foot, apparently" before getting on a bus as Hollis imagines him "watching this on that huge screen in his office. The world as video game."
Inchmale tells Hollis that Bigend wants The Curfew to record a $15M-budget video of "Hard To Be One" for a Chinese car commercial before telling him that he thought it would be good for him and Heidi to check on Hollis, who might be in trouble. [715 characters]
Remotely tracking Hollis's purse like this via the electronic gadgets inside it, is just about possible with mobile phone Location Based Services technology.
However any GPS devices, which can provide a more accurate position fix, and which are reasonably ok for tracking vehicles or containers with external antennas, require a clear line of sight to at least 2 GPS satellites in the sky. Technically 4 satellites are needed to provide data to solve the spherical geometry equations including elevation or altitude above sea level and to decide which of the two valid solutions to the equations (on opposite sides of the globe) applies. The standard GPS software waits until the device has acquired timing signals from 4 satellites, a process which usually takes several minutes from when it is powered on.
Unless Hollis's purse is completely transparent to very weak radio signals, and is never taken into a vehicle or building, this is unlikely.
Even then the GPS device still needs to transmit its position, that it has fixed from the satellites probably via the mobile phone network. Such real time tracking devices do not communicate back up to the orbiting satellites, unlike the many mainstream media false depictions of the technology.
William Gibson is aware of the limitations of GPS tracking, as he earlier had Alberto explain to Hollis how he needs Bobby Chombo's skills to allow his Locative Art installations to work indoors.
UPDATE:
William Gibson has admitted that he had to revise his text at a late stage, just before the galley proofs stage (according to his appearance at the TUC conference centre in London) , when science fiction author and internet copyright and privacy activist Cory Doctorow pointed out that GPS does not work indoors, but that he might be able to triangulate off the three nearest cell phone base station masts.
