User's Manual

RF Characteristics
A DIVISION OF TRIMBLE
36 Hardware Overview
Receive Sensitivity
The receiver sensitivity is influenced by both user-defined settings and by external
environmental factors. These factors are:
Transmit Level
Gen2 “M” setting
Region of Operation
Receive sensitivity is strongly influenced by the amount of interference caused by the
reader’s own transmit signal. This interference can be reduced by reducing the transmit
level. ThingMagic always quotes the receive sensitivity at the highest transmit level (+27
dBm for the Nano), but 1 dB of sensitivity is typically gained for every dB that the
transmitter output level is reduced.
The Gen2 “M” setting influences how data is encoded when sent from the tag to the
reader. Higher “M” values send data at lower rates and are more noise immune,
increasing the module’s sensitivity. Lower “M” values send data at higher rates,
decreasing the sensitivity somewhat.
The region of operation is also a factor. The Nano has slightly better receive sensitivity in
the EU and India regions (865 to 868 MHz) than in the North American region and