Real time AIS tracking system for fishermen using microcontroller-based approach

Fishing activities in the waters of Banyuwangi are relatively intense. Local fishermen often venture 50 nautical miles from the coastline using small boats. These boats are lacking adequate communication and navigation equipment, causing difficulties in obtaining assistance during emergencies. This study aims to develop an Automatic Identification System (AIS) device to be installed on fishing boats. The AIS device developed for this research incorporates the STM32F4 microcontroller, CMX7032 Evaluation Board, VHF Antenna, and Global Positioning System (GPS) as its main components. The integration and configuration of each component will be elaborated in this paper. Performance testing has yielded promising results, as the AIS device was capable of transmitting data up to 10 nautical miles from the Base Station. Utilization of AIS technology would enhance safety and communication among fishermen. Through careful integration and configuration of these components, the AIS device effectively ensures that the fishermen’s positions are accurately tracked and communicated. The successful development and testing of this device underscore its potential to bridge the communication gap, offering timely assistance and enhancing the overall safety of these seafarers.


Introduction
This research aims to enhance the security and efficiency of small-scale fishing activities through the development of an enhanced Automatic Identification System (AIS) [1].This is crucial as small-scale fishing often occurs in remote and high-risk areas, necessitating a system that can help reduce risks and increase productivity [2].Within this study, an assessment of the needs and challenges faced by fishermen in small-scale fishing activities is conducted.Additionally, an analysis of existing AIS systems is performed to understand their strengths and weaknesses.Based on the analysis results, an enhanced AIS system with various additional features that better cater to fishermen's needs is developed.Subsequently, this upgraded AIS system is tested at several small-scale fishing locations in Indonesia [3].It is anticipated that the testing outcomes will demonstrate the capability of the enhanced AIS system to improve safety and efficiency in small-scale fishing activities [4].Furthermore, the enhanced AIS system can aid in the supervision and management of fisheries resources more effectively.With the implementation of this upgraded AIS system, fishermen engaged in small-scale fishing can mitigate safety risks at sea and elevate their fishing productivity [5].Moreover, the enhanced AIS system can also assist the government in more effective and sustainable supervision and management of fisheries resources [6].Overall, the development of this enhanced AIS system can bring positive impacts to small-scale fishing activities, especially in hard-to-reach and high-risk areas [7].This research is expected to serve as a foundation for the future optimization of AIS systems, thereby contributing to the well-being of fishermen and the sustainability of fisheries resources [8].The utilization of AIS on fishing boats is expected to aid fishermen in reporting their emergency situations and facilitate Search and Rescue (SAR) operations by relevant parties in case of maritime accidents [8].However, this solution still presents challenges.The issue that arises is that the cost of commercial AIS devices available in the market is not affordable for the fishing community [6].This is the driving force behind conducting research to develop an inexpensive AIS Transmitter that can be customized to meet the needs of the Banyuwangi fishermen [9].The prototype of the Automatic Identification System (AIS) Transmitter developed in this research is equivalent to AIS Class B. This device is capable of periodically transmitting the fishermen's position information, which will be monitored by VTS LPTK and other vessels equipped with AIS transponders [10].Additionally, a distress function is embedded as an additional feature in this device.In emergency situations, fishermen can activate this distress function to send messages to nearby VTS and AIS transponders [10].
The Automatic Identification System (AIS) is a system designed to transmit information between vessels and maritime traffic control centers (Vessel Traffic Control Centers, VTCC) using VHF radio signals [11].This system was first introduced in 2002 and has since become an international standard required for vessels with a gross tonnage above 300 and passenger vessels with a capacity exceeding 12 passengers.AIS is used to assist vessel traffic services (VTS) and enhance maritime navigation safety.AIS has undergone several technological developments since its introduction in 2002 [12].Recent research has focused on improving the accuracy and reliability of the AIS system and expanding its capabilities for uses beyond navigation and vessel traffic monitoring [13].
The Automatic Identification System (AIS) technology is a digital device used as a navigation instrument in maritime navigation.This device integrates Global Positioning System (GPS) technology, Very High-Frequency (VHF) radio technology, and information technology into one system.AIS enables the exchange of maritime data between ships, base stations, and other vessels [14].The exchanged data includes ship identity (MMSI, Call Sign, and ship name), ship position, direction, size, cargo type, and other important information [15].The initiation of AIS technology was by the International Association of Maritime Aids to Navigation and Lighthouse Authorities (IALA), followed by development and standardization by the International Maritime Organization (IMO), International Telecommunication Union (ITU), and International Electrotechnical Commission (IEC) in the early 2000s [16].Over time, AIS became mandatory for all passenger ships, tanker ships, and cargo ships with a Gross Tonnage (GT) 300 for international routes [17].Since 2008, AIS has also been mandatory for all domestic ships with a GT 500.Koto, J. and Amran, N.A ( 2016

Figure 1. Marine Automatic Identification System
Importance of using AIS as a navigation instrument has led to research efforts to develop affordable devices.Some research explored the development of low-cost AIS receivers using a fast time simulator based on the AIS CMX7042 chip [19].Similar research was conducted using the Radiometrix RX1 chip and the Arduino Uno R3 microcontroller [20].Referring to these research findings, the technical specifications for the developed AIS Transmitter are outlined as follows:

Method
The method employed in this research is the design and construction method with an engineering approach.The AIS Transmitter is developed by integrating several modules into a single unit.These modules consist of the STM32F4 microcontroller, AIS CMX7032 Evaluation Board (DE70321T), GPS Receiver, and Shakespeare VHF Antenna.

GPS Module
The GPS Receiver (Figure 4) is used to obtain position information, speed, and other dynamic information from GNSS (Global Navigation Satellite System) satellites.The Neo-6M GPS Receiver from U-blox is used in this research.This GPS Receiver has three advantages that support the design requirements of the AIS Transmitter: low power consumption, compact size, and affordability.

STM32F4 Microcontroller
The STM32F4 microcontroller (Figure 5) is one of the products from STMicroelectronics that utilizes the ARM Cortex-M4 32-bit architecture.It operates within a voltage range of1.8 to 3.6 volts.The STM32F4 microcontroller processes and controls data flow in the AIS system.Position data from the GPS receiver is compiled along with additional information such as MMSI (Maritime Mobile Service Identity) and ship name, then transmitted to the AIS data processor (CMX7032 Evaluation Board) via the C-Bus communication protocol.

CMX7032 Evaluation Board (DE70321T)
The DE70321T module (Figure 6) integrates the CMX7032 Chip with a 2-Watt Power Amplifier, Voltage Controlled Oscillator (VCO), Harmonic Filter, and Antenna Switching.In the AIS system, this module encodes position data, speed, MMSI, ship name, and other data into AIS Messages.

VHF Antenna
The developed AIS device uses a Shakespeare VHF Antenna.This antenna is 1.2 meters long with a 3dB gain and a maximum input power of 50 Watts.An example of the Shakespeare VHF Antenna is shown in Figure 7.

Result and discussion
The implementation of the AIS Transmitter device in this study refers to the specifications outlined in Table 1.The configuration begins by assembling all modules and connecting them to the power supply unit.The STM32F4 microcontroller is set up to acquire position data from the GPS receiver and embed additional information such as the MMSI (MMSI 525150296 was used for testing purposes).The STM32F4 is then connected to the CMX7032 Evaluation Board using the C-Bus communication protocol.The next step involves uploading the function image to the CMX7032 Chip, containing the message encoding settings (AIS Message).

Conclusion
It can be concluded that the prototype of the AIS Transmitter based on the STM32F4 microcontroller functions effectively.The modular concept employed proves to save time and costs in the development of this device.The packaging used only provides protection against seawater splashes, therefore further research is needed to design packaging that offers maximum protection for the device.
) classified AIS devices into six types: Class A, Class B, Base Station, Aids to Navigation (AtoN), Search and Rescue Transponder (SART), and Specialist AIS Transponder.Each device can operate on the maritime VHF frequencies of 161.975MHz (AIS channel 1 or channel 87B) and 162.025MHz (AIS channel 2 or channel 88B).Communication among AIS devices use the TDMA (Time Division Multiple Access) protocol established by ITU-R (2014).TDMA protocol regulates the usage of VHF channels by dividing each channel into 2250 time slots per minute.Each time slot can be used for 25.6 milliseconds to transmit AIS messages [18].

Table 1 .
Technical Specifications of AIS