Chapter 10 - DAB Measuring Range
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10.6
MER measurement (Modulation Error Rate)
In addition to measurement of the bit error rate, it is established practice with digital transmission to
also measure MER. It is defined in ETR290, e.g. for DVB-T, and can be applied to DAB in a similar
manner. MER is calculated from the DQPSK constellation points.
It is the counterpart to S/N measurement with analog transmission methods. The measuring range
extends up to 25 dB with a resolution of 0.1 dB.
10.7
FIC decoding
Once the measuring receiver has locked in on a DAB signal, the DAB frame is analyzed. The data
of the FIC (Fast Information Channel) are then analyzed. This contains information on the
composition of the ensemble. For DVB, this corresponds to evaluation of PAT, PMT and SDT. The
instrument then creates a program list and displays this on the TFT. This is performed in a similar
manner as for DVB (see chapter 12.1 - Program Service Information (PSI)).
The decoder lists the names of all audio programs contained in the ensemble.
Pure data streams are not included. DAB+ programs receive an additional label. If the list
comprises multiple pages, you can switch between pages of the program list using the ← and →
keys.
10.8
MSC decoding and audio playback
You can play a program from the list by moving the cursor onto the desired program name using
the ↑ and ↓ keys.
When
ENTER
is pressed once, the decoder lists the corresponding program details Extracted from
the main service channel (MSC).
Figure 10-3 DAB program details
This includes the program name, program provider, service ID, DAB type and the audio data rate of
the particular program. The example above is for a DAB+ program with 72 kbit/s.
Pressing
ENTER
again starts audio playback and the sound can be monitored using the internal
speakers or the headphone jack. Pressing again stops playback of the current program, and the
program list again appears on the screen.
