User's Manual

COBALT UHF-SERIES CHAPTER 3: CONFIGURING THE COBALT
PAGE 38 OF 140

Choose Nearest, Instruct the reader to return only the information of the tag
with the stronger signal, which can be assumed is the “nearest” in space,
even if in real world condition this might be not always true.
Furthermore, users may retrieve or set the desired UHF configuration settings by
clicking on the buttons “Get UHF Config” and “Set UHF Config”.
3.2 NOTE ABOUT THE READER POWER
The performance of a UHF reader depends on the
radiated
power, not simply on the
reader output power that can be set with the above parameter. The radiated power
depends on the reader output power, the cable attenuation and the antenna gain.
The radiated power limits are set by the different governments (see table below for
details).
REGION REGULATIONS RADIATED POWER
USA FCC Part 15
4 W EIRP (36 dBm)
Europe EN 302 208
2 W ERP (35 dBm)
Table 3-1:Reader Radiated Power Limits
The UHF-CNTL-XXX-02 controllers produce up to 500 mW output power.
EXAMPLE OF A CALCULATION:
Radiated Power = Reader Power + Antenna Gain – Cable Losses
500 mW (27dBm) + 6.85 dBi - 1.5dBm = 32.35 dBm (~1.7 W ERP)
3.3 CONFIGURING THE COBALT VIA “CONFIGURATION
TAG”
As noted, the Cobalt UHF controllers are software configurable via the Cobalt
Dashboard Utility. However, they can also be configured through the use of the
Cobalt UHF Configuration Tag supplied with each unit.
The Configuration Tag can be used to restore the factory default values for all
versions of the Cobalt UHF RFID Controller.
3.3.1 Restoring Factory Defaults
1.
Place the Configuration Tag in the antenna’s RF field.
2.
Cycle power to the controller or issue the “Reset Controller” command
(Command 0x35).
As power returns to the unit, the LEDs will blink.
3.
After the LEDs blink, remove the Configuration Tag from the antenna’s RF field.
Factory default values have been restored.