The Ingenuity helicopter mission on Mars was originally planned to last for only 30 days, during which time it would conduct a technology demonstration to test the feasibility of powered, controlled flight on the planet. However, after the initial flights were successful, NASA decided to extend the mission and transition it to a new phase, where the helicopter would act as a scout for the rover. The extension posed several challenges, one of which was the prediction of telecommunication links in adverse scenarios involving complex surface topology and non-line-of-sight (NLOS) conditions. To address this challenge, our team at the Jet Propulsion Laboratory developed and demonstrated a highly accurate link budget prediction method using the parabolic equation method, which accounted for the actual surface topology of Mars. This approach was verified with 14 flight cases before being integrated into the mission operation tools to plan each helicopter flight and ensure the safety of this valuable asset, which has been operating on Mars for over two years.