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Cecil,
I do not expect that the reference you seek can be found. There is no need to invoke interference or wave cancellation to explain anything, and it is unlikely there is any mathematical formulation that uses interference as one of the input variables. It is totally unnecessary. Maxwell's equations contain everything needed to accurately describe electromagnetic interactions, including wave reflections, cancellations, and interference. Any serious treatment of the subject of electromagnetic interactions begins with the field equations, not with the resulting interference. The sort of description found on the Melles-Griot web site and on their CD-ROM is a handwaving, but comforting, description meant for general understanding, not for detailed analysis. 73, Gene W4SZ Cecil Moore wrote: Gene Fuller wrote: Cecil, You can't be serious! This is basic stuff found in virtually any intermediate level E&M textbook. If you can provide me with a reference that says, wave cancellation can cause reflection of the canceled waves, I will be eternally grateful. I have been able to find references that imply such for light waves, but I have not found one that comes right out and says it for either light waves or RF waves. I agree with you 100%. I had this "basic stuff" taught to me at Texas A&M half a century ago. But Roy's "food for thought" stuff completely ignores exactly that "basic stuff" concerning constructive/destructive interference. Nowhere in his arguments is "interference" even mentioned. I expect him to respond that interference is irrelevant. Dr. Best went so far as to deny that interference is necessary for a Z0-match to occur in a system with reflections. That was around May/June 2001 on this very newsgroup for anyone who wants to Google it. I have been fighting this battle for three years on this newsgroup. Now you say it's "basic stuff". I've agreed for three years, but where have you been all this time? The treatment is generally the same; start with the field equations describing the waves, add the material conditions and the boundary conditions, plug and crank. The answers pop right out. No need to invoke any magic incantations about interfering waves or wave cancellation. The interference is the result of the analysis, not the cause. Some people have forgotten what they learned in college. Their net/ steady-state shortcuts have become reality and scrambled their brains. You are obviously not one of the people at whom I aimed my remarks. I am glad to see that not everyone has been seduced into thinking that interference is irrelevant. In the classical case, there is absolutely no difference in behavior between "RF" and "optical". The material properties for every situation can vary, but the physical principles do not. I know that. You know that. We are on the same side. Now convince the RF gurus of that. Roy calculated the net power at the source and assumed from that figure that there was not enough energy available to support the energy in reflected waves. Sooo, rather than introducing a new concept, you are perhaps the last person to finally understand the old one. No, not the last one. What you say is exactly what is wrong with Roy's arguments that reflected energy doesn't flow from the load back toward the source. I am NOT introducing a new concept. I am introducing a new (or forgotten) concept to some of the RF gurus on this newsgroup. I am (re)introducing destructive/constructive interference concepts to Roy, Dr. Best, and others. |
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