COMMAND RANGING & TELEMETRY UNIT CORTEX
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Page 33
3.3.1.3.3. Supported PCM/FM demodulators
Two types of PCM/FM demodulators are supported in the Cortex:
1. The Legacy PCM/FM demodulator
that is based on the frequency discriminator approch. The dector
decision uses
only one symbol.
2. The Multi-sympol FM demodulator
(available under licence)
that takes benefit of the information
contained within the continuous phase to improve demodulator performances.
The following BER curve shows the performance gain obtained with the multi-symbol demodulator compared to
the legacy FM demodulator.
Figure 22 : BER Performances
– MS-FM demodulator versus Legacy FM demodulator
Note:
Multi-symbol curve is obtained in perfect conditions (no signal distortion, no variation on modulation index)
with
“Propagation factor” parameter set to 0.9,
