Friis Equation is used to find the ideal power received at an antenna from basic information about the transmission. The only inherent pitfall of Friis equation is the fact that it is only calculated for a single frequency, where transmissions are typically comprised of many. However, given a high enough center frequency, the difference in received power over the bandwidth should be reasonably small.
**Note: Like our Friis transmission equation calculator, all of our RF calculators allow SI prefix input. For example, if you wish to input "25000000", just type "25M" instead. See the quick-reference table below for all compatible SI prefixes.