TransCore AR2200, Руководство пользователя

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AR2200 RF Module Overview
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RF output power is on whenever the reader is on. However, RF output power may be
switched off through reader firmware commands. RF output power can also be con-
trolled through interfacing proximity sensors with the reader. Proximity sensors allow
RF output power to be switched on only in the presence of objects to be identified.
Proximity sensors are useful in installations using battery power or where continuous
RF output power is not desirable.
Increasing or decreasing the RF signal strength directly impacts the system's reading
range. To confine the reading range to its optimal area, RF power can be indepen-
dently adjusted, in eight steps, from +32.5 dBm to +25.5 dBm, for each antenna. You
can adjust the RF power with RF power select switches on the RF module’s input/out-
put (I/O) interface.
Caution
Do not attempt to increase the RF signal strength. Contact TransCore if you think
that you need to adjust the RF signal strength.
For ease of installation, the RF module is connected to the reader by cable attached to
a removable 21-terminal plug.
Features
The RF module includes the features listed in this section.
Range Sensitivity Adjustment
Jumper JP1 can be jumpered to inhibit the effect of the range sensitivity adjustments.
When JP1 is jumpered the maximum broadcast range will be ensured. This may be
done when the RF module is used in a traffic monitoring system where the maximum
size read zone is desired. Sensitivity circuit potentiometers, one for each antenna,
access an infinite range of settings from maximum broadcast range (range sensitivity
adjustment OFF, no mask signal injection) to maximum signal injection (minimum
sensitivity).
ISO Compatible
The RF module meets the criteria for equipment configuration and performance spec-
ified by the International Organization for Standardization’s DIS 10374 container
identification standard.
Patented Design: High-Speed Signal Capture,
Noise Immunity
The RF demodulation circuitry consists of a two-channel homodyne receiver patented
by TransCore that prevents signal loss, allowing the system to read tags moving at
high speeds. The differential aspect of the RF module design improves system
immunity to noise.
Frequency Range
The RF module is available in a range of 865–930 MHz band frequencies (see Table
2-1).
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