fading和path loss的区别是？

前者主要是由于多径
后者主要是由于传播距离

谁说fading一定是变小？

难道fading可以compensate?

小尺度的好想是 +10 - -30dB的样子， 对于蜂窝

这个答案是正确的理解吗？

我觉得不是，passloss也是fading。
passloss fading
shadow fading
multipath fading -1 time selective fading -2 frequency selective fading

fading 包括 large-scale fading 和 small-scale fading
large-scale fading 包括 path loss 和 shadowing
small-scale fading 就是 multipath fading,比如 Rayleigh,Ricean

正解，哈哈

a singal power drops off due to three effects:
mean progation loss (pathloss): comes from inverse square law  
         power loss  absroption by water and foliage and the
         effect of ground reflection  range dependent
macroscopic(long term/shodowing) : a blocking effect by                    
buildings and natural      features  
microscopic(shortterm/fast):the constructive and destructive combination of
    multipaths