NXP Semiconductors MKW01Z128, Reference Manual

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Sub 1 GHz Transceiver Architecture Description
MKW01xxRM Reference Manual, Rev. 3, 04/2016
Freescale Semiconductor, Inc. 5-19
It is therefore important to note that the setting of OokFixedThresh will be application dependant. The
following procedure is recommended to optimize OokFixedThresh .
Figure 5-8. Floor Threshold Optimization
The new floor threshold value found during this test should be used for OOK reception with those receiver
settings.
5.7.11.2 Optimizing OOK Demodulator for Fast Fading Signals
A sudden drop in signal strength can cause the bit error rate to increase. For applications where the
expected signal drop can be estimated, the following OOK demodulator parameters
OokPeakThreshStep
and OokPeakThreshDec can be optimized as described below for a given number of threshold decrements
per bit. Refer to RegOokPeak to access those settings.
5.7.11.3 Alternative OOK Demodulator Threshold Modes
In addition to the Peak OOK threshold mode, the user can alternatively select two other types of threshold
detectors:
• Fixed Threshold: - The value is selected through OokFixedThresh
• Average Threshold - Data supplied by the RSSI block is averaged, and this operation mode should
only be used with DC-free encoded data.
5.7.12 Bit Synchronizer
The Bit Synchronizer is a block that provides a clean and synchronized digital output, free of glitches. Its
output is made available on pin DIO1/DCLK in Continuous mode and can be disabled through register
Set SX1231 in OOK Rx mode
Adjust Bit Rate, Channel filter BW
Default OokFixedThresh setting
No input signal
Continuous Mode
Optimization complete
Glitch activity
on DATA?
Monitor DIO2/DATA pin
Increment
OokFixedThresh
MKW01