Update radio-settings.md

Added data-rates

docs/radio-settings.md

@@ -28,3 +28,14 @@ The maximum output power for North America is +30 dBm ERP.
 
 The band is from 902 to 928 MHz. It mentions channel number and its respective channel frequency. All the 13 channels are separated by 2.16 MHz with respect to the adjacent channels.  
 Channel zero starts at 903.08 MHz center frequency.
+
+## Data-rates
+
+Various data-rates are selectable when configuring a channel and are inversely proportional to the theoretical range of the devices:  
+
+|       Channel setting      |     Data-rate        |
+|----------------------------|----------------------|
+| Short range (but fast)     | 21.875 kbps          |
+| Medium range (but fast)    | 5.469 kbps           |
+| Long range (but slower)    | 0.275 kbps           |
+| Very long range (but slow) | 0.183 kbps (default) |