LoRaWAN Spreading Factor Table & its Application

Spreading factor: It defines how many chirps per symbol are used to encode the data. Spreading factors (SFs) range from SF7 to SF12 in LoRaWAN network.

• Higher SF means longer symbol duration and slower data rate but longer range & stronger signal robustness. Example : SF12
• Lower SF means shorter symbol duration and faster data rate but less range/robustness. Example : SF7

Following equation relates symbol duration, bandwidth and spreading factor (SF) mathematically.

=> Symbol Duration = 2^SF/Bandwidth

Significance of Spreading Factor (SF)

• Different SFs are quasi-orthogonal, meaning devices using different SFs can transmit simultaneously on the same frequency with minimal interference.
• It helps in achieving trade-off between range versus data rate.
• It helps to optimize battery consumption by dynamically setting it based on airtime requirements.
• It helps in network capacity planning.

Spreading Factor in LoRaWAN Specifications

• SF7–SF12 are standard; higher SF = more robust but slower.
• Following tables mentions various SFs and corresponding LoRaWAN parameters for different regions in the world.

Table-1 : LoRaWAN spreading factor and data rate in Australia

Table-2 : LoRaWAN spreading factor and data rate in Europe

Table-3 : LoRaWAN spreading factor and data rate in USA

Table-4 : LoRaWAN spreading factor and data rate in INDIA

Spreading Factor Table (BW = 125 kHz, CR = 4/5)

Table-5 : Spreading Factor vs Parameters (BW = 125 kHz, CR = 4/5)

Note: (Values may vary slightly per chipset, region, and coding rate settings.)

Conclusion:

Spreading Factor (SF) controls the trade off between range, data rate and energy consumption in LoRaWAN. It is essential for link budget planning, battery life optimization and network capacity. LoRaWAN uses ADR to optimize SF dynamically based on link conditions.