AVT MAGIC TBR, Hardware And Software Manual

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INTRODUCTION
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1.5 Functionality
MAGIC TBR is implemented on a signal processor-based hardware platform which is
assembled in an optimised way and achieves best values in terms of power
consumption and reliability. The standard system has a demodulator/modulator
module for one Ensemble. If required, the system can be equipped with a further
module for a second Ensemble. Both Ensembles are completely independent from
each other – a separate break-in is also possible. For the break-in function per
ensemble three encoders are permanently running: one DAB+ and two DAB
Encoder allow you to replace all Audio service in any configuration regarding
bitrate, sampling frequency etc. The break-in signal can be monitored via a
Monitoring Decoder.
Repeater and Remodulator Function
In the standard operation mode, the system functions as classic Repeater (see
Figure 3). The DAB Ensemble is received by an antenna outside the tunnel, is
filtered digitally and processed. Via the tunnel antenna the signal is broadcasted
again. A GPS signal is not required for this function. However, inputs are available
for future extensions.
Depending on local situations (e.g. bad reception conditions) it can be helpful to use
the system permanently in Remodulator mode (see Figure 4). This mode can also
be used during configuration to adjust and optimise the antenna signals at a tunnel
entry.
Figure 3: Repeater Mode