Ho John Lee’s Weblog

While investigating fresnel zone impairment issues for a potential 29 km 2.4GHz link, I have been looking for a way to calculate the theoretical loss due to obstacles within the fresnel zone.

There are many online web calculators that will compute the fresnel zone radius and the 60% radius. If there are no obstacles along the link path that are within 60% of the fresnel zone radius, it is generally safe to ignore the signal losses due to fresnel zone interference. However, I’m having a difficult time finding a method to estimate the potential losses due to known obstacles within the fresnel zone radius.

I did come across a nice (Windows-only) free application for wireless network planning, called Radio Mobile, while looking at an overview on radio propagation.

See also the Radio Mobile Quick Start guide.

Update: figured out that I need to search for “knife edge diffraction loss calculator” and “rounded edge diffraction loss”.

Also found lots of useful web calculators at http://www.qsl.net/n9zia/wireless/page09.html.

and helpful overviews of microwave propagation and interference calculations at http://cispa.thesupernet.com/microwaves/basicmicrowave.htm and http://people.deas.harvard.edu/~jones/es151/prop_models/propagation.html.

This entry was posted on Monday, February 7th, 2005 at 2:54 am and is filed under Wireless. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.