AN4103

Transmitter parameters

Doc ID 023130 Rev 1

9/20

Figure 7.

Spectral mask measurement, 12.5 kHz narrowband channel spacing,

4.8 kbps data rate, 1.2 kHz frequency deviation

2.3

Unwanted emissions in the spurious domain

Spurious emissions are unwanted emissions in the spurious domain at frequencies other

than those of the desired carrier frequency and its sidebands associated with normal test

modulation.

A spectrum analyzer is used as an external receiver. The measurement is performed setting

SPIRIT1 without modulation and observing until 4 GHz as described in the ETSI [2]

subclause 7.8.

The measurement is split between two figures, showing the frequency ranges above and

below 1 GHz. In Figure 8 the unwanted spurious emission for frequencies below 1 GHz is

shown. This measurement is performed by setting the instrument with a resolution

bandwidth of 100 kHz, as requested in ETSI [2]. In Figure 9 the unwanted spurious emission

for frequencies from 1 GHz to 4 GHz is shown. This measurement is performed by setting

the instrument with a resolution bandwidth of 1 MHz, as requested in ETSI [2]. In the two

figures the mask request from ETSI is also shown. Also, for the narrowband equipment, the

unwanted emission in the spurious domain test has to be done at all frequencies except the

channel on which the transmitter is intended to operate and its adjacent and alternate

channels. A zoom of the zone near the carrier is taken in Figure 10, Figure 11 and Figure 12

just to show that the ETSI specification is also met near the carrier.

The unwanted emissions in the spurious domain of SPIRIT1 comply with ETSI [2] subclause

7.8.

-90

-80

-70

-60

-50

-40

-30

-20

-10

0

10

1.6790E+08

1.6840E+08

1.6890E+08

1.6940E+08

1.6990E+08

1.7040E+08

1.7090E+08

Frequency [Hz]

- 36 dBm

- 36 dBm

- 30 dBm

AM16350v1