Polarization performance study of a GPS antenna mounted on a small t-tail aircraft in landing position using EM modeling

On-board Global Positioning System (GPS) antenna performance is critical for GPS-based navigation aids to provide a precision approach and landing for aircrafts in airports. The GPS antenna has to meet performance requirements to achieve an acceptable level of signal detection. These requirements include upper hemispherical Right Hand Circular Polarization (RHCP) coverage from zenith down to near horizon. This paper aims to study the polarization performance of a GPS antenna mounted on an aircraft at landing position. The antenna was mounted on the fuselage of the aircraft. Aircraft-level radiation pattern of the GPS antenna was simulated using the electromagnetic (EM) modeling abilities of the feldberechnung bei körpern mit beliebiger Oberfläche (FEKO) software package. An aircraft Computer-aided Design (CAD) model was created to mimic the Bombardier Global 5000 commercial aircraft. FEKO was also used to design the standalone microstrip patch GPS antenna. Landing aircraft position was conceived via running simulations above Perfect Electric Conductor (PEC) medium. The RHCP Pitch and Roll planes radiation pattern of the GPS antenna is presented. Statistical analysis for the three dimensions (3D) RHCP radiation patterns is provided. Finally, the antenna response to different polarizations is discussed.