Terrain optimization method for low-frequency ground-wave propagation delay calculation
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摘要: 附加二次相位因子(ASPF)是影响长波信号传播时间延迟的主要因素. 积分方程方法计算ASPF适用于地形复杂的路径，是目前广泛使用的计算方法. 它在推导过程中使用了稳定相位积分的近似方法，在地形起伏剧烈地区不再适用. 实际传播路径地形起伏变化巨大，通过数学形态法对实际传播路径修正，可以使路径保留基本几何轮廓并且光滑. 积分方程方法计算结果表明: 利用数学形态法可以有效优化处理实际传播路径.
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关键词:
- 积分方程方法 /
- 附加二次相位因子(ASPF) /
- 数学形态学 /
- 长波时延预测 /
- 地形优化处理
Abstract: The additional secondary phase factor (ASPF) plays an important role in propagation delay of the low-frequency ground-wave. A method of calculating attenuation for ground-wave propagating over irregular terrain called integral function has been developed recently. It is derived by means of a stationary-phase integration that reduces the dimensionality of the general version, but such an approximation is not valid for all terrain types. The terrain of the actual propagation path changes greatly, and the actual propagation path is corrected by the mathematical morphology method to keep the basic geometric contour and smoothness of the path. The calculation results of the integral equation method show that the actual propagation path can be effectively optimized through the mathematical morphology method. -
[1] 熊皓. 无线电波传播[M]. 北京: 电子工业出版社, 2000. [2] FOCK V. Diffraction of radio waves around the earth's surface[J]. Journal of physical, 1945(15): 479-496. [3] WAIT J R, HOUSEHOLDER J. Mixed-path ground wave propagation, II. larger distances[J]. Journal of research of the national bureau of standards, 1957(59): 19-26. DOI: 10.6028/jres.059.003 [4] MILLINGTON G. Ground-wave propagation over an inhomogeneous smooth earth[J]. Journal of the institution of electrical engineers, 1949, 96(39): 53-64. DOI: 10.1049/pi-3.1949.0013 [5] HUFFORD G A. An integral equation approach to the problem of wave propagation over an irregular surface[J]. Quarterly of applied mathematics, 1952, 9(4): 391-404. DOI: 10.1090/qam/44350 [6] 周丽丽, 穆中林, 蒲玉蓉, 等. 不规则地形地波传播衰减因子的改进算法及结果一致性研究[J]. 电子与信息学报, 2015, 37(9): 2254-2259. [7] MATHERON G. Random sets and integral geometry[M]. New York: Wiley, 1975. [8] SERRA J. Introduction to mathematical morphology[J]. Computer vision, graphics, and image processing, 1986, 35(3): 283-305. DOI: 10.1016/0734-189X(86)90002-2 [9] 潘威炎. 长波超长波及长波传播[M]. 成都: 电子科技大学出版社, 2004. [10] SOMMERFELD A N. The propagation of waves in wireless telegraphy[J]. Annals of physics, 1926, 386（25）: 1135-1153. DOI: 10.1002/andp.19263862516 [11] WATSON G N. The diffraction of radio waves by the earth[J]. Royal sociaty, 1918, 666(95): 83-99. DOI: 10.1098/rspa.1918.0050 -
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