AIS data case study : evaluating reception of AIS position reports on the Missouri River by LOMA AIS sites in April and August 2020

Abstract

This Coastal and Hydraulics Engineering Technical Note (CHETN) describes a method for evaluating the received coverage from Automatic Identification System (AIS) shoreside sites along the Missouri River managed by the US Army Corps of Engineers (USACE) Lock Operations Management Application (LOMA), and presents the results of that analysis. The purpose is to identify AIS coverage gaps in the current system. Reception of AIS transmissions between shore-based transceivers and vessels is generally line-of-sight between the vessel and the AIS site antenna. However, signal reception may be affected by factors such as the distance and terrain between the vessel and the transceiver site, quality of the transceiver installation, state of the equipment either aboard the vessel or at the shore transceiver station, and atmospheric phenomena. Quantifying coverage gaps along the inland waterways system can inform research that uses AIS data, provide information on the performance of the AIS network, and provide guidance for efforts to address coverage gaps to improve navigation safety. In autumn 2020, severe shoaling was occurring on the Missouri River. As the shoals were identified, the Kansas City District requested the LOMA system transmit AIS Aid to Navigation (AtoN) to mark the shoals in several critical areas. However, vessel pilots sometimes reported that they were not receiving the AIS AtoN being transmitted. At the request of the Kansas City District, the US Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory (ERDC-CHL), conducted a coverage analysis using data collected from the LOMA AIS transceivers in the area to determine if there were coverage issues and their extent and to aid in determining the best means of addressing any coverage gaps.

A method for evaluating Automatic Identification System (AIS) coverage on select inland waterways in 2020 and 2021 : Upper Mississippi River, Illinois River, and Ohio River

“…Therefore, not all AIS signals transmitted by vessels are received by shore AIS stations and vice versa. Vessels transmit AIS position reports depending on their dynamic condition; the frequency varies from 2 s up to 3 min (Table 2) (ITU-R 2014; Tetreault et al 2022). Vessel AIS stations can transmit other types of messages, but this study focused on position reports transmitted by vessels and received by terrestrial AIS stations along portions of the US inland waterway system.…”

“…Vessel AIS stations can transmit other types of messages, but this study focused on position reports transmitted by vessels and received by terrestrial AIS stations along portions of the US inland waterway system. AIS transceivers receive transmissions from AIS-equipped vessels transiting these waters and transmit information to vessels to be used for safe navigation, including AIS Aids to Navigation (Tetreault et al 2022).…”

“…The highest antenna in the LOMA system is located at the Glasgow site on the Missouri River at 123.4 m high. The Glasgow site can receive signals from approximately 150 mi of river due to a combination of factors including height and local terrain (Tetreault et al 2022). Raising an AIS antennae height has been shown to improve signal reception at another site on the Missouri River (Tetreault et al 2022).…”

“…The Glasgow site can receive signals from approximately 150 mi of river due to a combination of factors including height and local terrain (Tetreault et al 2022). Raising an AIS antennae height has been shown to improve signal reception at another site on the Missouri River (Tetreault et al 2022). This is known to be a simple and low-cost way to improve signal reception.…”

Virtual Aids to Navigation (VATONs) from the USACE LOMA program, 2018–2023

“…( 2). Although any LOMA shore site has the ability to broadcast VATONs, not all river miles are within range of a shore site (for discussions of LOMA shore-site coverage and broadcast ranges see DiJoseph et al 2021;Kilroy et al 2024;Tetreault et al 2022;and Zlotopolski et al 2023).…”