Baseband Processor For Mixed Mode Land Mobile Radio
CMX880
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Frame Sync Threshold / Tolerance
The frame sync threshold defines the level that the cross-correlation of signal with the frame sync pattern
must exceed before the CMX880 will detect a FS. The FS Cross-correlation Peak value can be read by “C-
BUS” command.
The frame sync tolerance code defines the maximum number of mismatches allowed during a search for the
Frame Sync pattern. The FS Mismatch count can be read by “C-BUS” command.
A single 'mismatch' is defined as the difference between two adjacent symbol levels, thus if the symbol '+1'
were expected, then received symbol values of '+3' and '-1' would count as 1 mismatch and a received
symbol value of '-3' would count as 2 mismatches.
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Select Clock Tracking Mode
allows the mC to change the symbol clock tracking mode if it perceives the Data Quality as deteriorating.
Modes: (1) Stochastic Gradient Clock Tracking Algorithm; or (2) Fixed Clock.
Select Level Tracking Mode
allows the mC to the change the symbol level tracking mode if it perceives the Data Quality to be
deteriorating. Modes: (1) Fast tracking; (2) Slow Tracking; (3) Partial Response Tracking; or (4) Fixed Level.
ã 2001 Consumer Microcircuits Limited
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D/880/1
CMLMICRO [ CML MICROCIRCUITS ]
