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3
rd
Generation Rack-
Mount RDMS™
41
Quasonix, Inc.
Differential encoding and decoding eliminates the phase ambiguity inherent with the received data. The differential
decoder can be enabled or disabled through the Main Menu by pressing Enter when the parameter is selected. The
Enter key acts as a toggle switch. Normal SOQPSK operation requires the differential decoder to be On. The default
value is On.
Differential encoding results in two differentially-decoded bit errors for each received bit error. This doubling
negatively impacts subsequent error-correction capability for block forward error correction. Since the Attached
Sync Marker used to identify block boundaries can also be used to resolve the phase ambiguity inherent in PSK
modulation, differential encoding is unnecessary for block forward error correction. Therefore, differential decoding
is automatically disabled when Reed-Solomon encoding is enabled.
Figure 54: Main Menu, Differential Decoding
4.4.2.15 HyperTrack
™
HyperTrack™ is an all
-digital antenna control protocol that offers many benefits in antenna tracking performance
and system operation. These benefits are too numerous and wide-ranging to describe fully here, but they include
improved tracking stability, range-based tracking bandwidth, ability to track through strong interfering signals,
rejection of incidental AM (e.g., from spinning test articles), and optimal multi-receiver tracking.
Enabling HyperTrack™ switches
the AM back panel output to all-digital mode. This mode requires a
HyperTrack™
-compatible ACU for proper operation and to take advantage of the performance improvements.
Disabling HyperTrack™ switches the AM back panel output to legacy analog AM mode.
Note, in a HyperTrack™
-equipped receiver, the Sync Detect digital status output is unavailable. Also, when
HyperTrack™ is enabled, the Lock Detect digital status output automatically becomes a copy of the HyperTrack™
digital output data. The lock detect output defaults to fixed 0 if the HyperTrack
™
back panel is present. Refer to the
Digital Status Output (DSO) command in the RDMS
™
Access via Telnet and Serial Control Protocol Technical
Guide for additional information.