Performance Specifications for the Roll-Off Factor and Filter Order for Filtered Multitone Modulation in the Maritime VHF Data Exchange System

The Maritime VHF Data Exchange System (VDES) will be a basic method of data exchange in the e-Navigation strategy, which has been developed by the International Maritime Organization (IMO) and is an application of the Internet of Things (IoT) in the maritime field. Based on the filtered multitone (FMT) modulation principle of the VDES, we systematically analyzed the effects of the filter parameters on communication performance in FMT modulation. Then, we simulated the influence curve of the roll-off factor and filter order with regard to the communication quality in VDES FMT modulation. Moreover, we performed an experiment using a software-defined radio platform in a real-world scenario. Finally, based on the simulated and real-world results, we recommend performance specifications for the roll-off factor and filter order for FMT modulation in the VDES.