Modems; Modem Configuration; Figure 8-1: Lora /(G)Fsk / Lr-Fhss Command Order - Semtech LR1121 User Manual

8. Modems

8.1 Modem Configuration

The LR1121 contains different modems capable of handling different constant envelope modulations. For the
LoRa®/(G)FSK modems and LR-FHSS modulation, the suitable command order is the following:
• The user must specify the modem to be used in command SetPacketType(...)
• SetModulationParams(...) configures the modem parameters (SF, BW, CR and LDRO)
•
SetPacketParams(...) defines the RF packet parameters (Payload length, Implicit/explicit mode, ...). This
command is not needed for LR-FHSS
• SetPaConfig(...) configures the PA settings used for RF packet transmission (which PA, supply mode...)
• SetTxParams(...) defines the PA parameters (output power, ramp time).
The suitable command order is the following:
LR1121
User Manual Rev 1.1
UM.LR1121.W.APP Mar 2023
SetPacketType
GFSK/LoRa®/GMSK (LR FHSS)
SetModulationParams
SF, BW, CR, LDRO, bitrate, fdev
SetPacketParams
PreambleLength, Implicit/Explicit,CRC, InvertIQ
SetPAConfig
PaSel, RegPaSupply, PaDutyCycle, PaHpSel
SetTxParams
Power, RampTime

Figure 8-1: LoRa /(G)FSK / LR-FHSS Command Order

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