수중 통신 성능 분포도 기반 벡터 센서노드의 최적 배치 연구

Abstract

An underwater acoustic sensor network (UWASN) is a system that passes information to the sensor nodes adjacent to sensor nodes that collect various types of data in the ocean environment. UWASN has recently attracted considerable attention because of their usefulness for a variety of military and civilian applications, such as ocean environmental monitoring, ocean exploration, target detection, surveillance systems, and communication between underwater sensor nodes. The goal of this dissertation is to develop a methodology for UWASN that includes the effects of underwater channel modeling based on dynamic environment, communication Performance Surface (PS) using vector sensor nodes and the optimal deployment of sensor nodes. A number of studies for sensor deployment have been performed using a uniform arrangement under the assumption that all sensor nodes have the same communication range. However, the communication performance is significantly influenced by temporal and spatial variations in the ocean environment, which may cause degradation of the efficiency of the deployed sensor nodes. In this dissertation, four effective sub-algorithms are proposed to improve the performance of UWASN in the ocean environment. The first step is underwater channel modeling based on a deterministic channel model and an environmental database (containing attributes such as the sound speed profile, bathymetry, and sediment property). The second step is the communication PS indicating the communication coverage of sensor nodes based ocean environmental data in the target area. The third step is the use of a vector sensor for processing, which has many advantages (small size, communication performance, and so on). The last step is optimal deployment algorithms of sensor nodes using the VFPSO, which combines the advantages of Virtual Force Algorithm (VFA) and Particle Swarm Optimization (PSO). Lastly, this dissertation includes a simulation to evaluate the performance of the optimal deployment algorithm in the ocean environment, and its effectiveness is verified by comparing the communication coverage rate and connectivity rate. |수중 음향 센서 네트워크는 해양 환경에서 다양한 데이터를 수집하여 인접한 센서 노드에 정보를 전달하는 시스템이다. 이러한 통신 센서 네트워크는 최근 해양 환경 모니터링, 해양 탐사와 같은 민수 분야와 수중 표적, 수중 감시 체계, 수중 분산 통신망과 같은 군사분야에 적용되므로 많은 관심을 끌고 있다. 따라서 본 연구의 목적은 해양 환경을 기반으로 수중 채널 모델링, 벡터 센서를 이용한 통신 성능 분포도 그리고 센서 노드의 최적 배치 알고리즘을 수중 센서 네트워크 연구에 포함하는 방법론을 제시하는 것이다. 기존의 센서 노드를 최적 배치하는 연구들은 동일한 통신 반경을 가지는 센서 노드를 가정하여 균일한 배치가 수행되어 왔다. 하지만, 수중 통신 성능은 해양 환경에 많은 영향을 받고, 이는 실제 해역에 센서 노드를 배치 할 경우 효율성을 저해하는 원인으로 작용하므로 더욱 효율적인 방법이 모색되어야 한다. 본 연구에서는 해양 환경을 고려한 수중 센서 네트워크의 성능을 향상 시키기 위한 목적으로 효율적인 네 가지 알고리즘을 제안하였다. 첫 번째 알고리즘은 해양 환경 데이터베이스(음속 구조, 해저 지형, 해저 저질 성분)과 확정적 채널 모델 기반 수중 채널 모델링이고, 두 번째 알고리즘은 목표 해역에서 센서 노드의 통신 범위를 나타내는 통신 성능 분포도 모델이다. 세 번째 알고리즘은 높은 통신 성능과 작은 크기의 장점을 가지는 벡터 센서를 이용한 통신 기법이다. 마지막으로 최적 배치 알고리즘인 VFA와 PSO의 장점을 결합하여 적용된 센서 노드의 최적 배치 알고리즘이다. 본 연구에서는 해양 환경기반으로 센서 노드의 최적 배치 성능을 평가하기 위한 시뮬레이션이 수행되었고, 통신 면적과 연결성을 비교 함으로써 알고리즘의 효율성을 검증하였다.; An underwater acoustic sensor network (UWASN) is a system that passes information to the sensor nodes adjacent to sensor nodes that collect various types of data in the ocean environment. UWASN has recently attracted considerable attention because of their usefulness for a variety of military and civilian applications, such as ocean environmental monitoring, ocean exploration, target detection, surveillance systems, and communication between underwater sensor nodes. The goal of this dissertation is to develop a methodology for UWASN that includes the effects of underwater channel modeling based on dynamic environment, communication Performance Surface (PS) using vector sensor nodes and the optimal deployment of sensor nodes. A number of studies for sensor deployment have been performed using a uniform arrangement under the assumption that all sensor nodes have the same communication range. However, the communication performance is significantly influenced by temporal and spatial variations in the ocean environment, which may cause degradation of the efficiency of the deployed sensor nodes. In this dissertation, four effective sub-algorithms are proposed to improve the performance of UWASN in the ocean environment. The first step is underwater channel modeling based on a deterministic channel model and an environmental database (containing attributes such as the sound speed profile, bathymetry, and sediment property). The second step is the communication PS indicating the communication coverage of sensor nodes based ocean environmental data in the target area. The third step is the use of a vector sensor for processing, which has many advantages (small size, communication performance, and so on). The last step is optimal deployment algorithms of sensor nodes using the VFPSO, which combines the advantages of Virtual Force Algorithm (VFA) and Particle Swarm Optimization (PSO). Lastly, this dissertation includes a simulation to evaluate the performance of the optimal deployment algorithm in the ocean environment, and its effectiveness is verified by comparing the communication coverage rate and connectivity rate.