User Manual

6.2 Radiated Power Measurements
During measurements, the BRD4310A Radio Board was attached to a Wireless Starter Kit Mainboard which was supplied by USB. The
voltage supply for the Radio Board was 3.3 V. The radiated power was measured in an antenna chamber by rotating the board 360 de-
grees with horizontal and vertical reference antenna polarizations in the XY, XZ, and YZ cuts. The measurement planes are illustrated
in the figure below.
X
Z
Y
Figure 6.2. Illustration of Reference Planes with a Radio Board Plugged into the Wireless Starter Kit Mainboard
Note: The radiated measurement results presented in this document were recorded in an unlicensed antenna chamber. Also, the radi-
ated power levels may change depending on the actual application (PCB size, used antenna, and so on). Therefore, the absolute levels
and margins of the final application are recommended to be verified in a licensed EMC testhouse.
6.2.1 Radiated Measurements in the 2.4 GHz Band
The supply for the module (VDD) was 3.3 V provided by the mainboard; for details, see the BRD4310A schematic. The transceiver was
operated in continuous carrier transmission mode. The output power of the radio was set to 0 dBm based on the conducted measure-
ment.
The fundamental was set to the frequency where the maximum antenna gain was measured. The results are shown in the table below.
Note: The frequency in which the antenna gain has its maximum value can vary between modules due to the technological spreading
of the passive RF components and the antenna.
Table 6.1. Maximums of the Measured Radiated Powers in EIRP [dBm]
Frequency EIRP [dBm] Orientation Margin [dB] Limit in EIRP [dBm]
Fund 0.3 XY/H 29.2 30.0
2nd
<-50
*
-/- >10 -41.2
3rd
<-50
*
-/- >10 -41.2
4th
<-50
*
-/- >20 -30.0
5th
<-50
*
-/- >10 -41.2
* Signal level is below the Spectrum Analyzer noise floor.
As shown in the table above, due to the antenna gain, the fundamental is slightly higher than the output power based the conducted
measurement. The harmonics are below the Spectrum Analyzer noise floor.
6.2.2 Antenna Pattern Measurements
The measured normalized antenna patterns are shown in the following figures.
BRD4310A Reference Manual
RF Performance
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