arduino-LoRa
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sandeepmistry
relation between Distance and (SF & BW & CR)
Hi there, what is exactly relation between Distance(between 2 module) and Values of SF & BW & CR?
I just know that I should increase SF and Tx Power when distance inceases.
There is no such mathematical equation for the wireless world. However, they are surely related.
Local regulation limits the TX Power. Normally up to 25dBm depending on where you live.
Sure there are calculations that can be done. In the RF world a 'Link Budget' calculation is a standard practice to get an idea of Link-to-Link performance (including theoretical distance). SemTech even provides the 'LoRa Modem Calculator Tool' to give you a lot of detailed information. This article give a pretty good overview of understanding these kind of calculations but always understand that there will be a lot of variance between different setups. https://medium.com/home-wireless/testing-lora-radios-with-the-limesdr-mini-part-2-37fa481217ff
There are some calculations. But not an exact caculation as wireless is not a perfect environment.
The calculation is only for a perfect no-obstacle environment.
As mentioned, there isn't an exact way to calculate the impact. However, as a rule of thumb, the higher the SF, and the lower the BW, and the slower, and longer range, the transmission will be. And vice versa.
