TransCore Amtech IT2200, Инструкция по установке, обслуживанию и ремонту

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IT2200 Reader System with Multimode Capability Installation & Maintenance/Service Guide
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that they are better able to distinguish between a nearby tag to be read and one slightly
more distant that is not to be read.
Passive backscatter tags do not transmit any RF, they merely modulate and reflect the
RF signal sent to them by the antenna. Beam-powered tags use the power from the RF
signal to reflect the modulated signal back, much as a mirror simply reflects light.
Beam-powered tags have an indefinite life expectancy, but are limited by a shorter
range.
When responding to a reader, active tags (ones that generate their own signal) add to
radio noise background whereas passive backscatter tags do not.
Depending upon the application, implementers can choose from read-only or read/
write models. Passive tags that are battery-powered or beam-powered, or active tags
(which are always battery-powered) can be chosen. Tags can also be selected with
different memory capacities.
Host Computer
The host computer must be capable of accepting data from the specific type(s) of
reader(s) being used in the system and variable bit formats, while offering flexibility
and expandability. Finally, the host computer must support multi-user, multi-tasking,
and multi-operating system environments.
The host computer performs many functions aside from directing the reader(s), such
as transferring the data received from the reader(s) to designated users, displaying it in
required form, and archiving it for reference.
The host computer may be used to provide other services such as controlling the
vehicle detectors, exit gates, and lights at a toll plaza.
Operational Characteristics
The performance of a given electronic identification system varies with the principles
of the systems and the details of implementation. The operational characteristics are
determined primarily by the following factors:
•
Reading range, or the maximum distance between the antennas and tag allowing a
successful read and/or write transaction
•
Maximum speed at which a tag on a moving object can be successfully read
•
Number of characters stored in the tag
•
Number of characters to be written to the tag
•
Coding format of the tag data
•
Sensitivity to tag orientation and placement
•
Immunity of the system to noise and interference