To solve the problem of the sky-wave interference in radio positioning system operating in CDMA mode, an algorithm of sky-ground-wave separation is provided. Based on the MLE （maximum likelihood estimate）, and by es...To solve the problem of the sky-wave interference in radio positioning system operating in CDMA mode, an algorithm of sky-ground-wave separation is provided. Based on the MLE （maximum likelihood estimate）, and by estimating the amplitude and the phase of the sky-wave signal, the provided algorithm for separating skyground-wave is implemented. The mathematics model used for signal processing is established, and the possible solutions are provided. The structure and signal processing flow implementing the presented algorithm in the receiver are presented. A multi-channels signal searching idea is adopted, some of which process the sky-wave signal, and some of which process the ground-wave signal. Numerical analysis and simulation show that the proposed algorithm has higher accuracy, more rapid processing speed, and simpler implementation for the estimation of the sky-wave signal parameter, and can separate the sky-wave signal and ground-wave signal from the arrival combination signal effectively.展开更多
海岸带是陆地、海洋、大气相互作用的地球生态关键带,汇集了大量的物质和能量,正经历着高强度人类活动、全球气候变化和物种入侵的叠加影响,面临着前所未有的挑战。遥感科学与技术是全面、系统、深入监测海岸带资源、生态、环境的有效...海岸带是陆地、海洋、大气相互作用的地球生态关键带,汇集了大量的物质和能量,正经历着高强度人类活动、全球气候变化和物种入侵的叠加影响,面临着前所未有的挑战。遥感科学与技术是全面、系统、深入监测海岸带资源、生态、环境的有效手段。本文从海岸带独特性和遥感技术优势出发,借助Web of Science和CNKI数据库,分析了海岸带遥感国内外研究现状,探讨了海岸带遥感所面临的科学技术问题,综述了研究进展,明确了机遇与挑战,讨论了未来发展方向。本文可为科学认识海岸带遥感中存在的问题,把握海岸带遥感发展方向提供参考。展开更多
文摘To solve the problem of the sky-wave interference in radio positioning system operating in CDMA mode, an algorithm of sky-ground-wave separation is provided. Based on the MLE （maximum likelihood estimate）, and by estimating the amplitude and the phase of the sky-wave signal, the provided algorithm for separating skyground-wave is implemented. The mathematics model used for signal processing is established, and the possible solutions are provided. The structure and signal processing flow implementing the presented algorithm in the receiver are presented. A multi-channels signal searching idea is adopted, some of which process the sky-wave signal, and some of which process the ground-wave signal. Numerical analysis and simulation show that the proposed algorithm has higher accuracy, more rapid processing speed, and simpler implementation for the estimation of the sky-wave signal parameter, and can separate the sky-wave signal and ground-wave signal from the arrival combination signal effectively.
文摘海岸带是陆地、海洋、大气相互作用的地球生态关键带,汇集了大量的物质和能量,正经历着高强度人类活动、全球气候变化和物种入侵的叠加影响,面临着前所未有的挑战。遥感科学与技术是全面、系统、深入监测海岸带资源、生态、环境的有效手段。本文从海岸带独特性和遥感技术优势出发,借助Web of Science和CNKI数据库,分析了海岸带遥感国内外研究现状,探讨了海岸带遥感所面临的科学技术问题,综述了研究进展,明确了机遇与挑战,讨论了未来发展方向。本文可为科学认识海岸带遥感中存在的问题,把握海岸带遥感发展方向提供参考。
