LoRa/LoRaWAN tutorial 10: RSSI and SNR

in this tutorial I will explain what our SSI and SNR are the received signal strength indication or our SSI is the receive signal power in milliwatts and is measured in DBM this value can be used as a measurement of how well a receiver can hear a signal from a sender in this picture I have not drawn the sender side I'm only interested in the receiver side this is the path loss down 10 again the cable and connector loss and this is the received signal strength indication or error SSI if signal strength indication is measured in DBM and it's a negative value the closer to zero the better the signal is typical Laura Eris's I values are the minimum our SSI value is minus 120 DBM if the our SSI value is minus 30 DBM the signal is strong and if the our SSI value is minus 120 DBM the signal is weak the signal-to-noise ratio or SNR is the ratio between the received power signal and the noise floor power level the noise floor is an area of all unwanted interfering signal sources which can corrupt the transmitted signal and therefore retransmissions will occur in this picture you will see two situations in this situation the SNR value is greater than 0 which means the receive signal operates above the noise floor and in this situation the SNR value is smaller than zero which means the received signal operates below the noise floor what you now here is the noise you can clearly see the receive signal operates above the noise floor so this is the receive signal normally the noise floor is the physical limit of sensitivity however Laura works below the noise level in this picture this is the noise floor power level and this is the received signal strength indication aka receive power level and as you can see the received power level is below the noise floor power level typical Laura SNR values are between minus 20 DB and plus 10 DB a value closer to +10 DB means the received signal is less corrupted Laura can demodulate signals which are minus 7.5 TP to minus 20 DB below the noise floor you thanks for watching I hope you enjoyed the video please hit the like button and don't forget to subscribe if you have questions leave your comments below I'll do my best to answer them

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Keywords: LoRa/LoRaWAN tutorial 10 RSSI and SNR, LoRa tutorial 10, LoRaWAN tutorial 10, LoRa, LoRaWAN, RSSI, SNR, Received Signal Strength Indication, Signal to Noise Ratio, LoRa RSSI, LoRa SNR, LoRa minimum RSSI, noise floor, received power signal, noise floor power level, received signal power, received signal, LoRa demodulation

Id: RpTw1fGhI68

Length: 3min 49sec (229 seconds)

Published: Fri Sep 28 2018