iPhone Satellite Waveform: An Experimental Performance Evaluation

Mobile satellite communications are gaining more and more interest in recent years, with SOS-via-satellite, location updating and satellite mobile messaging being important applications for customers. An efficient satellite waveform is the key technology to enable the mobile satellite communication service that will be provided by satellite constellations in the 5G and 6G era. In this paper, we conduct an experimental evaluation of the satellite waveform transmitted by the first satellite-enabled smartphone, the iPhone 14. We forced the device to transmit location data via L-band using the Find My application, while it had no other connectivity than the Globalstar satellites. The results show the temporal and spectral properties of the satellite waveform, and we performed a first estimate of the modulation scheme and data rate.