TransCore Amtech IT2200, Инструкция по установке, обслуживанию и ремонту

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Theory of Operation
2-9
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Frequency and power
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Tag lifetime
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Tag read/write accuracy rate
Reading Range
A well-defined reading range (sometimes called a capture window) is required for
successful performance of any ID system. This region is a volume of space extending
outward primarily from the front of the antenna.
Tags outside the reading range do not reflect enough RF signal to be processed by the
reader. Read/write tags may not receive a strong enough modulated signal from the
reader to be able to interpret the command being transmitted.
Reading Speed
Reading speed capability of a system is limited by the need to receive a complete code
frame (a tag's encoded message) while the tag is within reading range. Because signal
reception does not always start at the beginning of the tag's message, the system must
be designed to receive 10 full code frames to ensure reading an entire message.
Reading speed can be extended by
•
Decreasing the number of characters (length of message) stored in the tag
•
Increasing the volume of the reading range
Number of Characters Stored in Tag
For the IT2200-series tags, the number of characters stored in the tag consists of 16
pages of 16 bytes (128 bits) for a total of 256 bytes of data.
Number of Characters Written to an IT2200-Series Tag
From 1 to 16 bytes of data can be written to a specified frame during a write
command. If you only want to write one byte of data, then that byte has to be the most
significant byte. The IT2200-series tags do not support byte addressing.
Coding Format of the Tag Data
The coding format of the data written to the tag varies depending on tag configuration
and customer requirements.