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Q.
The waves used for line-of-sight $(LOS)$ communication is
J & K CETJ & K CET 2014Communication Systems
Solution:
The space waves are the radio waves of very high frequency $(30 \,MH _{2}$ to $300 \,MHz$, ultra high frequency $(300\, MHz$, to $3000 \,MHz$ ) and microwave (more than $3000 \,MHz$. Thus, space wave propagation can be utilised for transmitting high frequency $TV$ and $FM$ signals.