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What actually is NLOS propagation?

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I started this article several weeks ago and I am pleased to see it is still here so hopefully it was a reasonable attempt. Either that or nobody else is very interested in it. I suspect the popularity of 802.11 WLANs, mobile/cellular has broadened the interest in NLOS where networks are actually designed to take advantage of multipath reflections. Prior to that on VHF/UHF TV, FM broadcast the general advice was to give up if your antenna was not LOS to the transmit antenna. Further comments very welcome.ChrisAngove 21:03, 19 September 2006 (UTC) i guess it's different for AM. i read once that the illegal "blowtorch" radio stations near the border between the US and Mexico could be heard in Russia. the radio waves apparently travelled from the acapulco area OVER the arctic and then into the vicinity of Moscow. (this allegedly allowed KGB agents to brush up on their fluency in English and Spanish.) certainly not line of site transmission. or is this just an urban legend? i have a hard time beleiving the one could tune in to an AM station located ON THE OTHER SIDE OF THE WORLD, even if line of sight transmission isn't necessary. —Preceding unsigned comment added by 71.232.104.233 (talk) 10:30, 8 December 2009 (UTC)[reply]

NLOS artillery

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The newest US army weapon, should a new page be created?--70.82.165.99 (talk) 01:10, 27 February 2009 (UTC)[reply]

See Non-Line-of-Sight Cannon and Indirect fire. It isn't a radio topic. Jim.henderson (talk) 03:10, 27 February 2009 (UTC)[reply]

citations

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Article is quite intensive; Could benefit from a thorough rewrite by someone with knowledge that can make it easier to understand. May also need additional citations to support unsourced sections. --RichardMills65 (talk) 03:38, 13 March 2012 (UTC)[reply]

refraction

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" radio waves whose initial trajectory is towards the optical horizon will in fact follow a path which does not return to the Earth's surface at the horizon, but slightly beyond it." I believe this is backwards. I would expect thicker air at bottom to produce a downward bending, not upward. As described refraction would result in a reduction of coverage area, not a 4/3 increase. Upward bending means the rays that would have reached the optical horizon are lost into space not available for ground based reception further away. The upward curved ray path would be more vulnerable to obstructions, including the earth's simplified sphere/elipsoid, along the path from transmitter to receiver while downward bending paths can straddle obstacles, including the optical horizon, to a limited extent. It isn't what happens to the rays aimed at the horizon that extends range but the ones aimed over the horizon. The radio wave rays aimed at the optical horizon should fall short due to refraction bending them downward but some rays that originally would have gone over the horizon and been lost (for most purposes) into space are bent downward and hit the earths surface at points further away than the optical horizon. If you do a google image search for "refraction radio horizon" you will find numerous images that show the rays being bent downward as I describe and how this extends the radio horizon beyond the optical horizon. Whitis (talk) 21:07, 10 July 2013 (UTC)[reply]

Orphaned references in Non-line-of-sight propagation

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I check pages listed in Category:Pages with incorrect ref formatting to try to fix reference errors. One of the things I do is look for content for orphaned references in wikilinked articles. I have found content for some of Non-line-of-sight propagation's orphans, the problem is that I found more than one version. I can't determine which (if any) is correct for this article, so I am asking for a sentient editor to look it over and copy the correct ref content into this article.

Reference named "Seybold":

  • From Radio propagation: Seybold, John S. (2005). Introduction to RF Propagation. John Wiley and Sons. pp. 3–10. ISBN 0471743682.
  • From Low frequency: Seybold, John S. (2005). Introduction to RF Propagation. John Wiley and Sons. pp. 55–58. ISBN 0471743682. Archived from the original on 2021-04-16. Retrieved 2020-11-30.

I apologize if any of the above are effectively identical; I am just a simple computer program, so I can't determine whether minor differences are significant or not. AnomieBOT 22:28, 14 January 2023 (UTC)[reply]