Millimeter-wave-based Drone Automatic Landing-guidance System for Advanced Maritime Operations

Abstract

Drones have gained increased interests from a variety of fields such as logistics and environmental measurements. In the maritime domain, their applications are wide spreading, including cargo transportation, weather observation, fishery exploration, red-tide monitoring, port management, and detection of illegal ships. However, safely navigating drones to ships is challenging due to the swaying caused by waves and the occurrence of poor visibility conditions such as fog and rain. To address this challenge, our team has been investigating a novel automatic landing-guidance system using high-resolution millimeter-wave radar, which is tolerant to weather conditions. With this system, radio frequency identification (RFID)-based wide-range navigation and passive-landing port-based surface-inclination estimation are implemented to consistently guide drones located at a distance to the landing point. Specifically, the system consists of a wide-range flight-guidance method and a surface inclination-estimation method, both of which require a millimeter-wave radar mounted on a drone. The flight-guidance method, called MilliSign, uses corner reflector array-based RFID tags and enables a drone to be guided to a landing point by using the embedded information and position information of the tag. The inclination-estimation method uses a special arrangement pattern of corner reflectors and enables precise inclination of the landing port on a swaying ship for determining the appropriate start time of landing descent. This article investigates the overall system, which consistently guides a drone at a distant point to a landing point for all-weather operation.