SAMSys MP9311 Series, User Manual

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MP9311 User’s Guide
12
Setting Transmit Power - TD0
Output power on the MP9311 is set by configuring the Transmit Power (TD0) register.
The output power is entered in tenths (1/10) of dBm with steps of 1/10 dBm. All
values are in decimal. For example, entering a value of 121 equates to 12.1 dBm.
For example, to set the MP9311 output power to 17.5 dBm, issue the following
CHUMP command to the reader:
}Cw,d:TD0,b:175!
The valid range of values for TD0 is from 0 (0 dBm) to 280 (28 dBm).
Setting Antenna Gain - TG0 (MP9311-Wxx only)
In order to comply with ERP and threshold limits according to EN 302 208,
MP9311-Wxx models must be configured with the proper antenna gain. Antenna gain
is set by the TG0 register. Before operation, you must determine the actual antenna
gain used in the installation, G
A
.
To program the TG0 register, issue the following CHUMP command to the reader:
}Cw,d:TG0,b:xxx,f:1!
Where:
xxx is computed as follows: xxx = (G
A
(db) + 13.0) * 10
The range of allowable xxx is 000 through 230 which gives an allowable antenna gain
range of -13dB to +10dB. Proper LBT operation according to EN 302 208 is not
guaranteed with antennas outside of this range.