Knowing the gain (Gr in dB) of the receiving antenna, the distance from the satellite to the receiving antenna on earth (Km), the frequency that the satellite operates at (GHz), the radiated power of the satellite (in Watts) and the gain of the satellite antenna (dB) this app will return the EIRP (dBW), path loss (dB) and the received power of the earth station antenna.

To test this, use d = 40000, Pt = 10, Gt = 17, Gr = 52.3 and f = 11, "Calculate" should yield EIRP = 27.0, Path loss = -205.3 and the received power Pr = -126.0.