A multizone RF read/write system for conducting transactions with vehicles
traveling at high speeds. A first RF read zone is created, preferably by
use of a first gantry that extends over at least one lane and contains at
least one RF source that creates a large powerful RF read zone for
reading or reading and writing to a transponder on a passing vehicle.
Additional RF read zones arranged in tandem with the first RF read zone
are created by at least one additional RF source that is located on an
additional gantry extending over at least one lane, or located on the
first gantry. Accordingly, multiple RF read zones are created to conduct
transactions with passing vehicles. In one aspect, the multiple RF read
zones can be used to ensure that tolling transactions with a single
vehicle are more likely to be completed and have a higher degree of
accuracy. In another aspect, the multiple RF read zones each employ a
different RF technology so that multiple types of RF toll tags can be
read and written.