Quasonix RDMS, Инструкция по установке и эксплуатации

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3
rd
Generation Rack-
Mount RDMS™
67 Quasonix, Inc.
Figure 100 illustrates BCS Off.
Figure 100: Best Channel Indicator Off (Grey)
4.4.2.19.9 Time Aligner
The Time Aligner option is only available with the Combiner option enabled and set to On. The Time Aligner can
be disabled or enabled. When disabled, it remains Off and does not affect the combiner.
Figure 101: Advanced Menu, Time Aligner Selection
Enabling the (combiner) time aligner, as shown in Figure 101, lets it determine when to operate (with no user
intervention).
Maximal ratio combining can only achieve optimal performance if the Channel 1 and Channel 2 input signals are
accurately phase- and time-aligned. Traditionally, diversity combiners have performed phase alignment only, relying
on the telemetry system design to provide adequate time alignment.
However, there are cases in which time alignment cannot be easily guaranteed. Such cases include frequency
diversity and spatial diversity, where the propagation of transmit and receive paths for Channel 1 and Channel 2 may
be quite different through cables, equipment, and the air. As bit rates continue to increase, fixed latency differences
are magnified in relation to the bit period.
The Qua
sonix RDMS™ Combiner can perform both phase alignment and time alignment of the Channel 1 and
Channel 2 signals. The Time Aligner is capable of correcting up to ±1300 nanoseconds of time skew between