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什么叫自由空间，自由空间传播损耗如何定义？
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什么叫自由空间，自由空间传播损耗如何定义？
时间：2022-04-21 11:33
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大学试题
工学
移动通信技术
电子与通信技术
答案解析
自由空间：无任何衰减、无任何阻挡、无任何多径的传播空间。无线电波在自由空间传播时，其单位面积中的能量会因为扩散而减少。这种减少称为自由空间传播损耗。自由空间传播损耗LS=32.44+20lgf（MHz）+20lgd（km）dB
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