LoRa

1 Key Concepts

1.1 Spreading Factor

1.2 Coding Rate

1.3 Signal Bandwidth

2 TX

• Static configuration registers can only be accessed in Sleep, Standby or FSTX mode
• The LoRa FIFO can only be filled in Standby mode
• Data TX is initiated by sending TX mode request
• Upon completion the TxDone interrupt is issued and the radio returns to Standby mode
• Following transmission the radio can be manually placed in Sleep mode or the FIFO refilled for subsequent TX operation

LoRa TX data FIFO filling:

• Set FifoPtrAddr to FifoTxPtrBase
• Write PayloadLenght bytes to the FIFO (RegFifo)

3 Schematics

http://modtronix.com/prod/imod/inair4/inair4_r1_sch.pdf

4 Chip

4.1 SX1278

SX1278 Datasheet

• http://www.semtech.com/wireless-rf/rf-transceivers/sx1278/
• http://www.semtech.com/images/datasheet/LoraLowEnergyDesign_STD.pdf
• http://www.semtech.com/images/datasheet/LoraDesignGuide_STD.pdf
• http://www.semtech.com/images/datasheet/AN1200.19_SX127x_RefDesign_STD.pdf
• http://www.semtech.com/images/datasheet/an120014-xo-guidance-lora-modulation.pdf

5 Reference

• http://www.semtech.com/wireless-rf/rf-transceivers/
• http://cpham.perso.univ-pau.fr/LORA/RPIgateway.html