7.2.1 Radiated Measurements in the 434 MHz Band
For the 434 MHz radiated power measurements, an external whip antenna (P/N: ANT-433-CW-QW-SMA) was used as a transmitter
antenna. It was connected to the SMA connector of the BRD4173A Radio Board. The supply for the RF section (RFVDD) and the sub-
GHz power amplifier (SUBGRF_ON, SUBGRF_OP) was 1.8 V provided by the on-chip DCDC converter (for the sub-GHz PA it was
provided as VBIAS through the discrete balun); for details, see the schematic of the BRD4173A. The transceiver was operated in con-
tinuous carrier transmission mode. The output power of the radio was set to 10 dBm.
The measured radiated powers are shown in the table below.
Table 7.1. Maximums of the Measured Radiated Powers in EIRP [dBm]
Frequency
EIRP [dBm]
Orientation
Margin [dB]
Limit in EIRP [dBm]
Fund
9.6
XY/V
2.5
12.1
2nd
-58.2
YZ/H
24.3
-33.9
3rd
-59.2
XZ/H
31.3
-27.9
4th
-50.6
YZ/V
22.7
-27.9
5th
-61.4
XZ/H
33.5
-27.9
6th
-45.2
XZ/H
17.3
-27.9
7th
<-50
*
-/-
>10
-27.9
8th
-48.5
XZ/V
20.6
-27.9
9th
<-50
*
-/-
>10
-27.9
10th
-57.3
XZ/V
29.4
-27.9
* Signal level is below the Spectrum Analyzer noise floor.
As shown in the table, the fundamental is below the regulation limit by 2.5 dB, the harmonic levels are also compliant with large mar-
gins.
7.2.2 Radiated Measurements in the 2.4 GHz Band
For the transmitter antenna, the on-board printed inverted-F antenna of the BRD4173A Radio Board was used (the R1 resistor was
mounted). The supply for the RF section (RFVDD) and the 2.4 GHz power amplifier (PAVDD) was 1.8 V provided by the on-chip DC-DC
converter; for details, see the schematic of the BRD4173A. The transceiver was operated in continuous carrier transmission mode. The
output power of the radio was set to 10 dBm based on the conducted measurement.
The results are shown in the table below.
Table 7.2. Maximums of the Measured Radiated Powers in EIRP [dBm]
Frequency
EIRP [dBm]
Orientation
Margin [dB]
Limit in EIRP [dBm]
Fund
11.8
XZ/H
18.2
30
2nd
-51.2
XZ/H
13.6
-37.6
3rd
-45.3
YZ/H
7.7
-37.6
4th
-50.7
YZ/V
20.7
-30
5th
<-50
*
-/-
>10
-37.6
* Signal level is below the Spectrum Analyzer noise floor.
As shown in the table, due to the high gain of the inverted-F antenna, the level of the fundamental is higher than 10 dBm. The harmon-
ics are compliant with the applied limits with large margins.
BRD4173A Reference Manual
RF Performance
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