ThingMagic Sargas User Guide
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14
4 Hardware Overview
4.1
Ports and Connectors
4.1.1.1 Antenna Connections
The Sargas supports two monostatic bidirectional RF antennas through two Reverse Polarity SMA (abbreviated
to “RP-SMA”) connectors: labeled ANT1 and ANT2 on the Sargas - Figure 9.
The maximum RF power that can be delivered to a 50 ohm load from the external port is 1.0 Watts, (+30.0
dBm). Depending on the antenna used and the local regulations for your region of operation, the maximum
permitted level may be lower than this.
The RF ports can only be energized one at a time, but the reader can be configured to alternate between
antennas many times per second, often resulting in the appearance of continuous reading on both antennas.
4.1.2
Figure 9: Sargas RFID Antenna Ports
Antenna Requirements
The performance of the Sargas is affected by antenna quality. Antennas that provide good 50 ohm match at the
operating frequency band perform best. The degree of antenna match is measured as a return loss, in negative
dBm units, with a higher numerical (more negative) value being a better match. Specified sensitivity
performance is achieved with antennas providing -17 dB return loss or better across the operating band.
Damage to the reader will not occur for any return loss of -1 dB or greater.
WARNING -
Damage may occur if antennas are disconnected during operation or if the Sargas
sees an open or short circuit at its antenna port.
WARNING -
To comply with FCC’s RF radiation exposure requirements, the antenna(s) used for this
transmitter must be installed such that a minimum separation distance of 22 cm is maintained between
the radiator (antenna) & people in front of the antenna at all times and must not be co-located or
operating in conjunction with any other antenna or transmitter unless appropriate additional proximity
restrictions are imposed.
