Satellite Machine-Type Communication for Maritime Internet of Things: An Interference Perspective

Satellite machine-type communication plays a crucial role in the maritime Internet of Things. The realization of such a system, i.e., the VHF data exchange (VDES) satellite system, however, faces many technical challenges. Due to its global broadcasting nature, the interference generated from the emissions of the VDES satellite space stations to the incumbent or future land systems in the same band is of major concern to the International Telecommunication Union (ITU) spectrum allocation. However, neither regulatory rules nor related studies have been specified or made available in the literature regarding such interference. This paper utilizes the electromagnetic power flux density (RFD) mask concept for evaluating and constraining the emission onto earth from a satellite space station. The mathematical analysis and derivation are based on the principle that the actual interference from a space station that a land system experiences is no worse than that from any other land system allowed by the regulations. We demonstrate the derivation of such a PFD mask from three closely related regulations on the legacy land mobile systems by the Electronic Communications Committee (ECC) and ITU and present the corresponding constraints imposed on the VDES satellite system and their impacts on the performance of the system.