REAL TIME RIGA
Project participants are equipped with a
portable trace-unit. It consists of a small handheld computer,
known as a PDA
(Personal Digital Assistant) in marketing terms. The PDA,
with a built-in telephone, is connected to a GPS-receiver
and an antenna to match. The PDA can be carried around in
your hand or in a bag, the antenna (the size of a matchbox)
needs to be worn (or stuck to e.g. the roof of a car using
the magnet) in such a way that is has a good line of "sight"
with satellites. The software developed for the PDA activates
(Global Positioning System)-receiver. By doing a triangular
(timing) measurement the receiver determines its position
on earth and comes up with the participant's location. This
metod results in coordinates with an accuracy of half a meter
up to several meters. On the small screen of the PDA these
coordinates are translated into pixels, so that the participant
gets a visual impression of the route he's taking.
The PDA-software developed for the project
maintains an always-on internet connection to a server at
RIXC and non-stop transmits the resulting coordinates in realtime.
Ths is taken care of by having the built-in telephone set
up a connection over the GPRS
(General Packet Radio Service)-network. GPRS is the so-called
2.5G network, where G stands for Generation, and is an in-between
technology between the current GSM-network and the 3G UMTS
network. It's not a broadband network yet in the way UMTS
promises (?) to be but has a higher bandwith and enables for
A computer (client) responsible for visualisation
is set up with Keystroke-software
developed by Waag Labs which fetches this data, again in realtime,
from the server and projects it in the exhibition space. This
software renders the participants' routes realtime as traces,
slowly but surely causing a map of the city to be constructed.
Spots on the 'map' which are visited or crossed often, gradually
change colour from white to yellow to red, showing the 'intensity
of use' of routes or locations.
(read more: http://www.waag.org/realtime)