Measuring DVB-T Signals - Digital Video and Audio Broadcasting Technology - page 389

Solomon decoders, measuring times of corresponding length in the range
of minutes up to hours must be selected.
Fig. 21.4. Bit error ratio measurement [EFA]
The measurement menu example [EFA] shows that all the important in-
formation about the DVB-T transmission is combined here. Apart from the
RF selected, it also shows the received level, the frequency deviation, all 3
bit error ratios and the decoded TPS parameters.
21.2 Measuring DVBT Signals Using a Spectrum
Analyzer
A spectrum analyzer is very useful for measuring the power of the DVB-T
channel, at least at the DVB-T transmitter output. Naturally, one could
simply use a thermal power meter for this purpose but, in principle, it is
also possible to use a spectrum analyzer which will provide a good esti-
mate of the carrier/noise ratio. Firstly, however, the power of the DVB-T
signal will now be determined. A COFDM signal looks like noise and has
a crest factor which is rather high. Due to its similarity with white Gaus-
sian noise, its power is measured in a comparable way.
To determine the carrier power, the spectrum analyzer is set as follows:
On the analyzer, a resolution bandwidth of 30 kHz and a video bandwidth