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demodulator_snr_db

pamoja_lora::budget

Function demodulator_snr_db 

Source 
pub fn demodulator_snr_db(spreading_factor: u8) -> Decibels
Expand description

Returns the signal-to-noise ratio the LoRa demodulator needs at a spreading factor, in dB.

These are the typical figures of Table 6-1 in the Semtech SX1261/2 datasheet, from -2.5 dB at SF5 to -20 dB at SF12, which Semtech TN1300.05 repeats per data rate. A negative ratio is a signal received below the noise, and each step up in spreading factor reaches another 2.5 dB further down.

§Arguments

  • spreading_factor - the spreading factor, clamped to 5 to 12 as LinkSettings::new clamps it.

§Returns

The required SNR in dB.