RFM63B Datasheet, PDF (28/90 Pages) List of Unclassifed Manufacturers – ISM TRANSCEIVER MODULE V1.1

ADVANCED COMMUNICATIONS & SENSING
RFM63B
RXParam_RSSI_val(7:0)
24 26 27 30 25 20 20 20 18 22 33 20 22 34 33
IRQParam_RSSI_irq
Clear interrupt
Figure 21: RSSI IRQ Timings
3.4.8. Fdev Setting in Receive Mode
The effect of the Fdev setting is different between FSK and OOK modes:
3.4.8.1. FSK Rx Mode
In FSK mode the Fdev setting, as configured by MCParam_Freq_Dev, sets sampling frequencies on the receiver.
The user should make it consistent with the frequency deviation of the FSK signal that is received.
3.4.8.2. OOK Rx Mode
The frequency deviation Fdev, as described above, sets the sampling rate of the RSSI block. It is therefore
necessary to set Fdev to the recommended low-IF frequency, IF2, of 100 kHz:
3.4.9. FSK Demodulator
The FSK demodulator provides data polarity information, based on the relative phase of the input I and Q signals at
the baseband. Its outputs can be fed to the Bit Synchronizer to recover the timing information. The user can also
use the raw, unsynchronized, output of the FSK demodulator in Continuous mode.
The FSK demodulator of the RFM63B operates most effectively for FSK signals with a modulation index
greater than or equal to two:
3.4.10. OOK Demodulator
The OOK demodulator performs a comparison of the RSSI output and a threshold value. Three different threshold
modes are available, programmed through the RXParam_OOK_thresh_type register.
The recommended mode of operation is the “Peak” threshold mode, illustrated below in Figure 22:
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