Applicability of the Langley Method for Non-Geostationary In-Orbit Satellite Effective Isotropic Radiated Power Estimation

The effective isotropic radiated power (EIRP) is a crucial parameter characterizing the transmitting antennas of a radio frequency satellite link. During the satellite commissioning phase, the requirements compliance of communication subsystems is tested. One of the required tests concerns the EIRP of the satellite transmitting antenna. Ground-based power measurements of the satellite-emitted signal are collected to measure EIRP, provided that an estimate of the atmospheric losses is available from independent ancillary measurements or model data. This article demonstrates the applicability of the so-called Langley method to infer EIRP and atmospheric attenuation simultaneously from ground-based power measurements, with no need for ancillary measurements. It is shown that the proposed method gives results similar to more traditional methods, without prior information on atmospheric attenuation. Thus, the proposed method can be applied to monitor EIRP throughout the satellite lifetime from ground-based power measurements alone.