Transmitter parameter

AN4378

12/19

DocID025421 Rev 1

The spectrum analyzer setting is the same of the peak power measurement procedure, with

some modifications. Set the analyzer center frequency to the frequency associated with the

restricted band emission under examination. Set the RBW equal to 1 MHz. If the peak

measured value complies with the average limit, it is not necessary to perform a separate

average measurement.

In Figure 9 the unwanted spurious emission between 10 MHz to 1 GHz is shown. In this

band the more stringent requirement is in the band 30 MHz to 88 MHz with the value of -56

dBm for the restricted bands as defined in 15.205. This requirement is fully met by the

BlueNRG. All the requirements within the 10 MHz to 1 GHz band are also fully met.

In Figure 10 the unwanted spurious emission between 1 GHz to 2.4 GHz is shown. The

spectrum detector is set to average, as required by the standard. In this band the FCC

requirement is -41 dBm for the restricted bands as defined in 15.205. This value is fully met

in the entire band.

In Figure 11 the unwanted spurious emission between 2.5 GHz to 26 GHz is shown. The

spectrum detector is set to average, as required by the standard. In this band the FCC

requirement is -41 dBm for the restricted bands as defined in 15.205. This value is fully met

in the entire band.

Figure 9. Spurious emission in restricted band measurement from 10 MHz to 1 GHz

AM17624v1

-70

-60

-50

-40

-30

-20

-10

1.0000E+07

1.1000E+08

2.1000E+08

3.1000E+08

4.1000E+08

5.1000E+08

6.1000E+08

7.1000E+08

8.1000E+08

9.1000E+08

Frequency [Hz]