Quasonix RDMS, Инструкция по установке и эксплуатации

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3
rd
Generation Rack-
Mount RDMS™
40 Quasonix, Inc.
If the receiver is locked and the delta h (the change in modulation index) has settled below the delta h threshold for
the specified settling time, the state changes to Triggered, and the eye pattern will turn Green. In Triggered mode,
the estimated h (modulation index) is monitored but the scale is not updated.
If delta h goes above the delta h threshold and settles again, the receiver is still locked, and the Eb/N0 at the settling
point is higher than the last settling point, the current scaling is updated with the new estimate. There is no transition
from Triggered back to Armed except for setting the mode to Acquire again.
4.4.2.13 Modulation Persistence (PCM/FM Mode Only)
The Mod Persist option allows the current state of the Mod Scaling setting to be retained following a power-off
cycle of the rack. The default value is Off, as shown in Figure 52.
Figure 52: Main Menu, Modulation Persistence
–
Off
To retain a Locked index number, or to remain in Acquire mode, scroll to the Mod Persist option, then toggle the
setting to On.
Figure 53: Main Menu, Modulation Persistence
–
On
4.4.2.14 Differential Decoding
Differential decoding is available in all PSK modes (SOQPSK and legacy BPSK, QPSK, OQPSK, AQPSK,
AUQPSK, and UQPSK). Legacy modes often use differential forms of PCM encoding (e.g., NRZ-M) instead, and
only one or the other form of differential encoding should be used at a time.