Main assumptions used

• Perfect noise floor (i.e. noise floor below receiver's sensitivity
• Perfect line of sight between the Tx and Rx (i.e. zero obstructions in the frenzel zone)
• For linear polarised antennas, both antennas are perfectly oriented to avoid all polarisation mismatch
• When using a linear and a circular polarised antenna, the loss is 3db
• All transmitters emit exactly their stated power
• Receiver assumed to have -85db sensitivity
• Range calculations use the standard link margin calculations
• The estimated range is the range at which the link begins to deteriorate. Pilots often accept some static and fly beyond that

For full details of the assumptions relating to each antenna type check out The complete list of FPV antennas