LMX2571을 활용한 자율해상무선기기 구현에 관한 연구 = A study for Implementation of Autonomous Maritime Radio Device Using LMX2571

다국어 초록 (Multilingual Abstract)

Even after the introduction of GMDSS, many maritime accidents and casualties are increasing. The representative method of transmitting a rescue signal when a person falls into the water on a ship is by pressing the V-Pass and VHF DSC buttons. In this case, it cannot be a complete solution.
IMO and others have recognized the need for communication equipment for personal safety in addition to communication equipment for ship safety, and have been conducting research and consultations to introduce MOB.
Among the WRC-19(World Radio Conference 2019) Agenda 1.9.1 “Regulatory measures within the frequency band 156-162.05 MHz for AMRD(autonomous maritime radio devices) to protect GMDSS and Automatic Identification Systems (AIS)”, VHF channels No.2006(160.9MHz) was newly allocated to AMRD applying AIS technology for class-B , including MOB devices.
Therefore, it is essential to develop a device that meets the general conditions of class-B and MOB technology using AIS technology, reduces cost and is easy to carry.

In this paper, an integrated device for miniaturization is selected for easy portability in the marine environment. AIS protocol implementation and message writing using microprocessor STM32L432 chipset, Gaussian modulation implementation using LMX2571 chipset and RF frequency 160.9MHz and terminal amplifier were designed.
Currently used AIS is to transmit 8 slots of 4 each with 2 channels (AIS1 & AIS2), but in this paper, 8 bursts were transmitted using one channel (No. 2006, 160.9MHz), and ​ Eight slots were allocated to one burst, and transmission was performed. The commercial VHF receiver was set to receive conditions by setting the local channel 2006 with NMEA Command. Designed and verified according to general and technical conditions. As the saturation of the existing AIS channel approaches 50%, new frequency utilization is required, and a prototype was implemented based on international standards.
In ITU-R M. 2135, the technical and operational characteristics of the transmitter are e.i.r.p. 100mW, they should not interfere with nor claim protection from other existing services, within the frequency tolerance ±500Hz, the spurious was met as -47dBm, and in this paper, the output was based on 30dBm.
Also, it was confirmed that the VDM message was received through normal transmission for data transmission (RATDMA and ITDMA communication techniques) using one allocated channel 2006, and displayed in conjunction with ECDIS. The designed and implemented AMRD MOB-AIS will be a way to secure communication in the marine environment in the future. In particular, it is expected that it will play a key role in the safety of crew members in the efficient operating environment of leisure and fishing boats, training ships, and government ships.

Research areas that need to be supplemented in relation to MOB-AIS devices in the future are research on transmission distance versus output, research on ways to expand the insufficient maritime mobile service identification code, and development of new application technologies such as radio buoys using AIS technology and institutional studies will be required.
On the other hand, the marine distress location indicator MOB-AIS based on the AIS technology must be attached to the body of the survivor or to the lifejacket, so it is necessary to downsize with the integrated circuit design must be introduced, and technical support such as this study is essential.

목차 (Table of Contents)

• 제 1 장 서 론 1
• 1.1 연구배경 1
• 1.2 연구목적 및 내용 4
• 제 2 장 디지털 통신 7
• 2.1 GMSK 변조 7
• 2.1.1 MSK(Minimum Shift Keying) 7
• 2.1.2 GMSK(Gaussian Minimum Shift Keying) 10
• 2.2 Two-point 변조 18
• 2.2.1 PLL(Phase Locked Loop) 18
• 2.2.2 VCO에 변조신호의 삽입 20
• 2.2.3 주 발진기에 변조신호의 삽입 23
• 2.2.4 VCO와 주 발진기에 변조신호의 삽입 26
• 2.3 직접 디지털 FSK 변조 28
• 2.3.1 직접 디지털 FSK 변조 개요 28
• 2.3.2 직접 디지털 FSK 변조 설계 고려사항 29
• 제 3 장 MOB-AIS 요건 분석 33
• 3.1 MOB-AIS 장치의 특징 33
• 3.2 물리계층 요구사항 분석 34
• 3.3 링크 계층 요구사항 분석 39
• 3.3.1 부-계층 1: 매체 접속 제어 (Medium Access Control, MAC) 39
• 3.3.2 부-계층 2: 데이터 링크 서비스 (Data Link Service, DLS) 42
• 3.3.3 부-계층 3: 링크 관리 실체 (Link Management Entity, LME) 47
• 3.4 네트워크 계층 요구사항 분석 59
• 3.5 전송 계층 요구사항 분석 59
• 3.5.1 전송 패킷 61
• 3.5.2 표시 인터페이스 프로토콜 61
• 제 4 장 MOB-AIS 장치의 설계 63
• 4.1 변조기 설계 63
• 4.1.1 FSK 변조기 설계 63
• 4.2 증폭기 설계 74
• 4.2.1 RF5110G를 이용한 150MHz FM 설계 74
• 4.3 GPS 수신기 설계 76
• 4.3.1 GPS 수신기 설계 일반사항 76
• 4.3.2 NEO-6 칩셋 특성 76
• 4.4 선박 자동식별장치 프로토콜의 설계 80
• 4.4.1 시분할 다중접속 전송 요구사항 80
• 4.4.2 시분할 다중접속 전송 구현 84
• 4.4.3 동기 요구사항 구현 87
• 제 5 장 MOB-AIS 장치의 제작 및 성능 분석 89
• 5.1 송신기 제작 89
• 5.1.1 송신기 회로 제작 89
• 5.1.2 송신기 Firmware 개발 94
• 5.1.3 안테나 제작 97
• 5.1.4 AIS 수신기 튜닝 98
• 5.2 성능 검증 105
• 5.2.1 송신기 기술기준(안) 105
• 5.2.2 송신기 성능 검증 107
• 제 6 장 결론 117
• 참고문헌 119