The speed at which tags pass through the IZ affects the number of tags that can
be read in a particular time interval (usually measured in seconds). The length
of time a tag spends in the IZ is called dwell time. By knowing the dimensions of
the IZ and direction and speed of tag travel, you can calculate dwell time. The
interrogator specifications should supply the number of tags it can read in 1 second.
This number is usually not very accurate to use however, because the manufacturer
does not provide details regarding how that number was calculated.A
single tag within an IZ may be read, for example, 1000 times per second, but
when multiple tags are placed in the IZ at the same time, that number does not
scale. With more than one tag in the zone, the interrogator has to use an
anti-collision algorithm to singulate the tags before reading them.