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Development of precise point positioning algorithm to support advanced driver assistant functions for inland vessel navigation

Lass C., Ziebold R.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

2021

Vol. 15 No. 4

781--789

Bridge passing and passing waterway locks are two of the most challenging phases for inland vessel navigation. In order to be able to automate these critical phases very precise and reliable position, navigation and timing (PNT) information are required. Here, the application of code-based positioning using signals of Global Navigation Satellite Systems (GNSS) is not sufficient anymore and phase-based positioning needs to be applied. Due to the larger coverage area and the reduction of the amount of correction data Precise Point Positioning (PPP) has significant advantages compared to the established Real Time Kinematic (RTK) positioning. PPP is seen as the key enabler for highly automatic driving for both road and inland waterway transport. This paper gives an overview of the current status of the developments of the PPP algorithm, which should finally be applied in advanced driver assistant functions. For the final application State Space Representation (SSR) correction data from SAPOS (Satellitenpositionierungsdienst der deutschen Landesvermessung) will be used, which will be transmitted over VDES (VHF Data Exchange System), the next generation AIS.

Simulation and measurement studies of the VDES system’s terrestrial component

Bronk Krzysztof, Koncicki Patryk, Lipka Adam, Rutkowski Dominik, Wereszko Błażej

Polish Maritime Research

2019

nr 1

95--106

In the paper, the measurement and simulation results of the VDES (VHF Data Exchange System) terrestrial component are discussed. It is anticipated that VDES will be one of the major solutions for maritime communications in the VHF band and its performance will be sufficient to fulfill the requirements of the e-navigation applications. The process of the VDES standardization (ITU R, IALA) has not been officially completed yet, but substantial amount of technical information about the future system’s terrestrial component (VDE-TER) is already available. The paper is divided into three general parts: (a) theoretical presentation of the system’s physical layer and the radio channels applicable to VDES, (b) simulation results (BER, BLER, channel delay between two propagation paths and its influence on bit rates) and (c) measurement results (useful ranges, BER). It turned out that in real maritime conditions, the VDES system can offer ranges between 25 and 38 km for the configurations assumed during the measurement campaign. Those results are generally compliant with the theoretical data in the line-of-sight conditions. In the NLOS scenarios, where fading becomes the dominant phenomenon, the discrepancies between the measurements and the theoretical results were more significant. The obtained results confirmed that VDES provides a large coding gain, which significantly improves the performance of data transmission and increases the bit rate compared to the existing maritime radiocommunication solutions. It should be noted that the results presented in the article were used by the IALA while developing the current version of the VDES specification.