I haven't followed this thread completely, so this has probably already been said:
The easiest was for me to think of the problem is with image theory. The source antenna has an "image" as far below the ground plane as it is above the ground plane. Solve for the hypotenuse of both triangles and take the difference for phase, remembering that the horizontally polarized image is 180 degrees out of phase to start with while the vertical image is in phase. For an approximation, use Friis equation to get the amplitude of each path and add them up. I say approximation because it assumes far field propagation, which may not be the case depending on the range and frequency. Hope that helps, Brent DeWitt, AB1LF Milford, MA -----Original Message----- From: CR [mailto:k...@earthlink.net] Sent: Saturday, August 01, 2015 8:01 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Calculating Reflection Angles on OATS/SAC On 7/31/2015 10:59 AM, Pawson, James wrote: > I can do this simply when the TX and RX antennae are the same height > above the reflecting surface as the point of reflection lies halfway > between the two antennae, Distance_tx = Distance_rx. The direct and > reflected paths can be calculated using simple geometry and the > wavelength is given by lambda = c / f. > However when the height of the RX antenna is different to the height > of the TX antenna then the horizontal distance to the reflection point > is no longer equidistant. I can see that the ratio Height_tx / > Distance_tx = Height_rx / Distance_rx remains the same because the > angle of reflection is the same. But I'm left with two unknown > Distance terms in the equation. - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <sdoug...@ieee.org> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
