Permissible values for unwanted emission intensity

AN4133

20/35

Doc ID 023362 Rev 1

4

Permissible values for unwanted emission intensity

Unwanted emissions in the spurious domain are emissions at a frequency other than those

of the desired carrier frequency and its sidebands associated with normal test modulation.

The spurious emission strength at the antenna input has to be less than the values in

Table 1 for the convenience radio stations and Table 3 for the low-power radio station. The

measurements for the convenience radio station are done with the carrier set to 922 MHz.

The measurements for the low-power radio station are done with the carrier set to

916.5 MHz.

The measurements performed for the convenience radio station are given in Figure 18 to 26

which show that all requirements are met. Special attention must be given to the

requirement in the 920.3 to 924.3 MHz band. In this band the levels of the spurious have to

be lower than -55 dBm on 100 kHz band without considering the channel occupied

bandwidth. This value is in obvious contradiction with the value reported in the convenience

radio station channel masks (Figure 4 and 6) where for the same spurious a maximum level

of -29 dBm integrated in 100 kHz bandwidth is given. In Figure 22 the two different masks

are shown and it is clear that the second requirement is much less stringent than the first

one.

The measurements performed for the low-power radio station are given in Figure 27 to 33.

For the low-power case the full requirements are met.

Figure 18.

Convenience radio station emission in the 10 - 710 MHz bandwidth

-70

-60

-50

-40

-30

-20

1.00E+07

1.10E+08

2.10E+08

3.10E+08

4.10E+08

5.10E+08

6.10E+08

7.10E+08

Frequency [Hz]

Convenience radio station spurious emission 10 - 710 MHz

Spirit

ARIB mask