Automatic Identification System Receiver Research Articles

Ship tracking results from state-of-the-art space-based AIS receiver systems for maritime surveillance

Norway currently operates four satellites with Automatic Identification System (AIS) receivers. The first-generation satellites, AISSat-1 and AISSat-2, are equipped with a two-channel, single-antenna AIS receiver, while NorSat-1 and NorSat-2 are equipped with an improved AIS receiver capable of decoding on all four AIS channels and using the two antennas installed on the NorSat satellites. This paper aims to investigate the ship tracking performance enhancement realised by the technology improvements of antenna diversification, frequency diversification, and advanced algorithms. The ship tracking capability of the NorSat satellites is presented and shown to yield a significant improvement, up to a 20% point increase, over the first AISSat generation ship tracking capability. A further 20% point increase is achieved in select areas using frequency diversity introduced in the AIS system since the development of the AISSat satellites. In addition, NorSat-1 detected 34% more vessels than AISSat-2 over the same timeframe. The contribution to the performance improvement from the incremental improvements in decoding algorithms, antenna diversity, and frequency diversity is indicated in the results. The results indicate that, in the short term, upgrading to the latest algorithms, low noise electronics, and taking advantage of antenna diversity is the greatest performance enhancer. In the medium and long term, the frequency diversity likely yields the greatest performance enhancement.

Thermal Validation Testing of an Automatic Identification System (AIS) Receiver for Low Earth Orbit (LEO) CubeSat

The advancements in electronics technology make nanosatellite missions more varied. One of its missions is to retrieve Automatic Identification System (AIS) data from vessels on the ground. The type of nanosatellite made in this study is a CubeSat with a size of 1.5U. The AIS receiver is created using RFIC Si4362 and MSP430G2553 Microcontrollers to control the device. The main mission of AIS Receivers is to receive and decode AIS signals at the frequency of 161.975 MHz and 162.025 MHz into the AIVDM NMEA0183 standard format. The decoded AIS data is sent to a Raspberry Pi Compute Module as On-Board Data Handling (OBDH) CubeSat before it is sent to the ground station. All of the CubeSat’s subsystems must be able to pass thermal testing before being launched into orbit. Thermal testing is performed to observe the performance of subsystems in extreme conditions similar to CubeSat conditions in space. Thermal testing is carried out at the Satellite Technology Center (Pusteksat) of the National Aeronautics and Space Agency (LAPAN) facility. The thermal test is done by running the device at temperatures of -20°C - 60°C for 3 hours and 56 minutes. The thermal testing indicates that the AIS Receiver can work in the orbital temperature range. After testing, the data reception success rate is 36.76% with a minimum RSSI value of -96dBm.

A Design of Space-borne AIS Scene Simulation Based on Density Distribution of Global Vessels

At present, the demand for application of space-borne Automatic Identification System (AIS) is increasing. Since more and more satellites are equipped with AIS payload, it is especially important to test the effectiveness of its performance. Owing to difficult test on AIS payload and high cost, this paper proposes a method of space-borne AIS scene simulation platform based on density distribution of global vessels, focusing on basic principle and design method of simulation scene. It contains detection range computing, the number of vessels within range and the detection probability of AIS receiver. Moreover, corresponding software and hardware have been designed. ‘Ocean-2B’ satellite-based AIS payload is used to test the performance of the scene simulation system, which indicates that the method can simulate real scene of receiving signals in orbit in a favourable manner.

Experimental test for receiving X-Band data LAPAN-A3 Satellite with 5.4m antenna diameter

LAPAN-A3 / LAPAN-IPB Satellite launched on June 22, 2016 (03:56 UTC) as an experimental micro-satellite for remote sensing and monitoring of maritime traffic. The Satellite was launched as a secondary payload on ISRO Cartosat-2C as its main payload, the launch carried out at SDSC (Satish Dhawan Space Centre) in India using PSLV-C34 rocket launcher. The Satellite was in orbit polar sun-synchronous with a height of 505 km above sea level. It has an inclination angle of 97 degrees and heavy satellite 115 kg, with this orbit, the satellite will pass through Ground station 4 times (2 times during the day and two times at night) with a duration of the track at the time of the pass about 10-15 minutes. The Satellite payload carried 4 bands Line Scan Cameras and Digital Imager (SpaceCam). For main mission is the earth observation for food vegetables And as additional mission is carrying AIS (Automatic Identification System) receiver to monitor maritime traffic in the region of the poles, then Star Sensor made by LAPAN for qualifying room, then for scientific contained magnetometer sensor for monitoring the Earth's Magnetic field. The purpose of this scientific paper is to test the reception of data payloads of the LAPAN-A3 satellite on X-Band frequency of 8.2 GHz using a 5.4 M solid antenna Ground Stations LAPAN in Pare-Pare. The purpose of this experiment will tell us with 5.4 meter of diameter solid antenna is capable or not enough for HDRM receiver to lock a signal and produce the data output, and how this result if compare with 11 meter of diameter antenna in Splitzberg Groundstation in Norway.

Study on fuzzy GIS for navigation safety of fishing boats

ABSTRACTMaritime ship collisions involving fishing boats have often been reported, and the major factors have been human error and unpredictable conditions. This paper aims to create a set of collision-avoidance measures for operating fishing boats or a vessel traffic service by way of time and space management. It proposes a novel safe collision-avoidance safeguarding ring for navigational safety between operating fishing boats and merchant ships with a dummy automatic identification system (AIS) to enable fishing boats to establish a dynamic state when approaching ships under operation (fishing). The approach method utilises the maximum relative speed, sea state, and escape time as three linguistic input variables for fuzzy logic control application. After the radius of the safeguarding ring is obtained and shown on a marine geographic information systems (MGIS) platform, the danger index of two ships is evaluated based on the area difference calculated through the MGIS. The software was installed in the dummy AIS receivers of fishing boats for experimentation in a Taiwan harbour. It was able to enhance the collision-avoidance ability of the operating fishing boats effectively and reduce marine disasters involving fishing boats.

Data Reception Analysis of the AIS on board the TianTuo-3 Satellite

The Automatic Identification System (AIS) receiver on board the main satellite of the TianTuo-3 constellation, LvLiang-1, is a new generation of AIS receiver. Having partly solved the signal conflict problems and with larger coverage over the ground, the AIS receiver on board TianTuo-3 greatly improves the signal detection ability. The data received by the AIS receiver during the TianTuo-3 debugging stage is employed for detailed analysis in this paper. Results include: TianTuo-3 implements four-frequency detection at the same time, and a time-flag is inserted into the received AIS data, a small portion of Class A vessels (at least 1480) have been equipped with AIS sending the long range AIS broadcast message with two new frequency channels and the hourly averaged count of the message received by TianTuo-3’s AIS is between 1500 ~ 2500. This AIS receiver is capable of real-time tracking a single vessel. In conclusion, the TianTuo-3 space-based AIS receiver is capable of continuously receiving AIS messages sent by global maritime vessels.

Design of Automatic Identification System (AIS) Receiver for Low Earth Orbit (LEO) Satellite

The vessel monitoring system at the sea with Automatic Identification System (AIS) technology will be more effective if AIS receivers are put on satellites because the satellite’s coverage can extend to thousands of kilometers when orbiting in the space. The process of receiving AIS signals in the space has a problem of low received power reaching -102.07 dBm. This value comes from the link budget calculation. This paper offers the design and simulation of a CubeSat AIS receiver payload that can operate to receive AIS signals in the orbit at the altitude of 650 km. The AIS receiver is designed to run at 161.975 MHz and 162.025 MHz using Gaussian Minimum Shift Keying (GMSK) modulation method. In this work, the AIS receiver is designed using radio frequency (RF) module Si4362 with operating temperature of -40° to +85° Celsius suitable for the space environment. Here, AIS signal modulation and demodulation methods were simulated using an electronic design automation software for radio frequency components. The simulation results showed the AIS receiver can receive AIS signals under appropriate conditions with link budget calculation. Finally, end-to-end AIS system simulations were carried through real conditions. The results showed the AIS system designed functions at full capacity.

Study on Safety of Navigation using Automatic Identification System for Marine Traffic Area Case Study: Malacca Straits

International Maritime Organization (IMO) has recommended the implementation of Automatic Identification System (AIS) to improve the safety of navigation at marine traffic area. Based on regulation, IMO requires AIS to be fitted aboard all ships of 300 gross tonnage and upwards engaged on international voyages, cargo ships of 500 gross tonnage and upwards not engaged on international voyages and all passenger ships irrespective of size. The function of the AIS is to make communication between ship to ship and communication between ship to the port or land area. In this study, the study area is the Malacca Strait. Malacca Straits is the strait categorized as high risk level. Malacca straits is also busy area for maritime transportation because it is an area for international transportation lines. Many captains feel anxious and cautiously when passes through the strait. AIS receiver was used in this study which has been installed at Universiti Teknologi Malaysia by Kobe University Japan. Using AIS receiver, the current condition of the ship in the Malacca Straits area can be monitored properly. In addition, the data recorded on the AIS receiver can be used for research to enhance safety of navigation.

Automatic Identification System modular receiver for academic purposes

AbstractThe Automatic Identification System (AIS) standard is encompassed within the Global Maritime Distress and Safety System (GMDSS), in force since 1999. The GMDSS is a set of procedures, equipment, and communication protocols designed with the aim of increasing the safety of sea crossings, facilitating navigation, and the rescue of vessels in danger. The use of this system not only is increasingly attractive to security issues but also potentially creates intelligence products throughout the added‐value information that this network can transmit from ships on real time (identification, position, course, speed, dimensions, flag, among others). Within the marine electronics market, commercial receivers implement this standard and allow users to access vessel‐broadcasted information if in the range of coverage. In addition to satellite services, users may request actionable information from private or public AIS terrestrial networks where real‐time feed or historical data can be accessed from its nodes. This paper describes the configuration of an AIS receiver based on a modular design. This modular design facilitates the evaluation of specific modules and also a better understanding of the standard and the possibility of changing hardware modules to improve the performance of the prototype. Thus, the aim of this paper is to describe the system's specifications, its main hardware components, and to present educational didactics on the setup and use of a modular and terrestrial AIS receiver. The latter is for academic purposes and in undergraduate studies such as electrical engineering, telecommunications, and maritime studies.

Enhanced AIS receiver design for satellite reception

The possibility to detect Automatic Identification System (AIS) messages from low earth orbit (LEO) satellites paves the road for a plurality of new and unexplored services. Besides worldwide tracking of vessels, maritime traffic monitoring, analysis of vessel routes employing big data, and oceans monitoring are just few of the fields, where satellite-aided AIS is beneficial. Designed for ship-to-ship communication and collision avoidance, AIS satellite reception performs poorly in regions with a high density of vessels. This calls for the development of advanced satellite AIS receivers able to improve the decoding capabilities. In this context, our contribution focuses on the introduction of a new enhanced AIS receiver design and its performance evaluation. The enhanced receiver makes use of a coherent receiver for the low signal-to-noise ratio (SNR) region, while for medium to high SNRs, a differential Viterbi receiver is used. Additional novelty of our work is in the exploitation of previously decoded packets from one vessel that is still under the LEO reception range, to improve the vessel detection probability. The assessment of the performance against a common receiver is done making the use of a simple and tight model of the medium access (MAC) layer and the multi-packet reception (MPR) matrix for physical layer (PHY) representation. Performance results show the benefits of such enhanced receiver, especially when it is bundled with successive interference cancellation (SIC).

Signal environment mapping of the Automatic Identification System frequencies from space

This paper presents received signal strength data recorded by the NORAIS Receiver on the four VHF channels allocated to the use of the Automatic Identification System (AIS). The NORAIS Receiver operated on-board the Columbus module of the International Space Station from June 2010 to February 2015. The data shows that a space-based AIS receiver must handle transient strong signals from land-based interference and that the effectiveness of the two long range AIS channels recently allocated is severely reduced in select areas due to land based interference.

A cyclic redundancy check-based non-coherent receiver for automatic identification system signals

Summary A non-coherent receiver for automatic identification system (AIS) signals is proposed in this paper. The proposed receiver is based on the Viterbi algorithm with cyclic redundancy check (CRC) trellis. It takes bit stuffing into consideration and is designed to simultaneously demodulate decode and correct the received messages. The complexity of the proposed receiver has been reduced with state-complexity reduction. Simulations prove that the proposed receiver outperforms those AIS receivers without CRC trellis error correction in terms of BER and packet error rate. Copyright © 2015 John Wiley & Sons, Ltd.

Global Maritime Surveillance by Airliner-Based AIS Detection: Preliminary Analysis

Demands on security, safety, and environmental protection in worldwide shipping are steadily increasing. Shipboard broadcast transponders based on the Automatic Identification System (AIS) can be easily detected close to coastal or waterway areas. Satellite-based AIS receivers detect globally but are limited in high-density traffic areas. This paper investigates the challenges and performance of AIS detection on aircraft at altitudes between 8 500 m and 10 000 m. During flight trials over sea and land, AIS signals were recorded. Post-processing of the recorded data allows the evaluation but also faces challenges due to the nature of overlapping AIS signals at the aircraft. A comparison of detected signals at the aircraft with received AIS signals on the ground is given, including the evaluation of the reception footprint of the aircraft. Finally, a concept for worldwide AIS detection via airliners is presented. The study shows the potential for global complementary surveillance coverage via airliner-based AIS detection.

Development of Risk Based Collision (RBC) Model for Tanker Ship Using AIS Data in the Malacca Straits

Analysis of ship collision is very important to establish in the field of maritime transport, especially in areas that have a high degree of risk. Strait of Malacca is international shipping that has a high degree of risk. In these areas, tankers have a high degree of probability of an accident. Based on AIS (Automatic Identification System), Tanker has seen the highest density of traffic volume density, reaching approximately 50% every day. In this paper, a risk analysis performed using the actual data from AIS. In this case, the value of the CPA (Closest Point Approach) and TCPA (Time to Closest Point Approach) obtained from AIS is used to generate the value of risk. After we know the value of a risk, it must be measures to avoid accidents ship on sea transportation. AIS data in this study were drawn from the AIS receiver that has been installed in Malaysia UTM.

Risk of Navigation for Marine Traffic in the Malacca Strait Using AIS

The Malacca Strait experiences high-density vessel traffic, and therefore is a busy area with high potential for collisions. Analyses of marine traffic that reflect the real conditions of ship navigation are performed to enhance maritime traffic safety. An automatic identification system (AIS) allows for the accurate investigation of actual ship encounters, ship collisions, and sea traffic management systems. For this study, an AIS receiver installed at the Universiti Teknologi Malaysia (UTM) provided AIS data, which focused on a selected area in the Malacca Strait. The 1972 International Regulations for Preventing Collisions at Sea (COLREG) guided the assessment of navigation safety based on real conditions using AIS and geographic identification systems (GIS). Based on estimates of the probability and consequence indices from a risk matrix, the time and encounter conditions determined the level of risk. This study also conducted safety measurements. The analysis indicated that ship safety would improve significantly if the vessels followed the guidelines established in this study.

Ship Exhaust Real-Time Monitoring System based on Automatic Identification System

Maritime traffic is a major source of pollutant gases and we believe that it is important to quantify these gases in order to assess their impact on the environment. This paper proposes a maritime monitoring system able to estimate in real time the emissions of carbon dioxide (CO2) and particulate matter (PM) from ships crossing the Strait of Gibraltar area. The system works based on the Automatic Identification System (AIS) : it consists of an AIS receiver connected to a computer in which was installed an application able to determine, store and display emissions from ships. The computer application was performed according to a method for estimating CO2 and PM emissions from AIS data. The system was installed near the Strait of Gibraltar (exactly in Tangier Morocco) and tests were carried out for about a month (between March 26 and April 23, 2014). The system recorded emissions from 900 to 4000 tons of CO2 and 2 to 9 tons of PM each day.

Applications of Ship Domain Theory to Identify Risky Sector in VTS Area

This paper describes the application method of bumper area defined in the ship domain theory and it is to identify risky sectors in VTS(Vessel Traffic Services) area. The final goal of this work is to develop early warning system providing the location information with high traffic risks in Mokpo VTS area and to prevent the human errors of VTS Officer(VTSO). The current goal of this paper is to find evaluation and detection method of risky sectors. The ratio between overlapped bumper area of each vessels and the summing area of a designated sector, Ratio to Evaluate Risk(RER) <TEX>${\gamma}$</TEX> is used as one of evaluation and detection parameter. The usability of overlapped bumper area is testified through three kinds of scenarios for various traffic situations. The marine traffic data used in the experiments is collected by AIS(Automatic Identification System) receiver and then compiled in the SQL(Structured Query Language) Server. Through the analysis of passing vessel's tracks within the boundary of Mokpo VTS area, the total of 11 sectors are identified as evaluation unit sector. As experiment results from risk evaluation for the 11 sectors, it is clearly known that the proposed method with RER <TEX>${\gamma}$</TEX> can provide the location information of high risky sectors which are need to keep traffic tracks of vessel movements and to maintain traffic monitoring by VTSO.

AISバイナリメッセージを用いた見張り情報の共有

As an application of the ASM (Application Specific Message) of AIS (Automatic Identification System), which is so called “binary message”, The author developed a system which shares information of the targets tracked by ARPA(Automatic Rader Plotting Aid) with other ships and boats equipped with AIS receivers. The system transmits two types of position data; one is absolute positions and the other is relative positions to the tracker. In 2013, for both data types, the accuracy of the tracked positions was evaluated at Tateyama comparing with the GPS data of a boat under tracking, and this paper reports the result.

Combined iterative cross-correlation demodulation scheme for mixing space borne automatic identification system signals

Aiming at the potential presence of mixing automatic identification system (AIS) signals, a new demodulation scheme was proposed for separating other interfering signals in satellite systems. The combined iterative cross-correlation demodulation scheme, referred to as CICCD, yielded a set of single short signals based on the prior information of AIS, after the frequency, code rate and modulation index were estimated. It demodulates the corresponding short codes according to the maximum peak of cross-correlation, which is simple and easy to implement. Numerical simulations show that the bit error rate of proposed algorithm improves by about 40% compared with existing ones, and about 3 dB beyond the standard AIS receiver. In addition, the proposed demodulation scheme shows the satisfying performance and engineering value in mixing AIS environment and can also perform well in low signal-to-noise conditions.

Methods for Processing and Interpretation of AIS Signals Corrupted by Noise and Packet Collisions

Methods for Processing and Interpretation of AIS Signals Corrupted by Noise and Packet Collisions The authors deal with the operation of Automatic Identification System (AIS) used in the marine traffic monitoring to broadcast messages containing information about the vessel: id, payload, size, speed, destination etc., meant primarily for avoidance of ship collisions. To extend the radius of AIS operation, it is envisaged to dispose its receivers on satellites. However, in space, due to a large coverage area, interfering factors are especially pronounced - such as packet collision, Doppler's shift and noise impact on AIS message receiving, pre-processing and decoding. To assess the quality of an AIS receiver's operation, a test was carried out in which, varying automatically frequency, amplitude, noise, and other parameters, the data on the ability of the receiver's ability to decode AIS signals are collected. In the work, both hardware- and software-based AIS decoders were tested. As a result, quite satisfactory statistics has been gathered - both on the common and the differing features of such decoders when operating in space. To obtain reliable data on the software-defined radio AIS receivers, further research is envisaged.