How to get envelope from AM signal without phase shift
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From: WWalker on 23 Mar 2010 06:48 Rune, Your arguments do not apply. First of all the fields in the nearfield are not plane waves and secondly, the superluminal effect is observed when the antennas are pointed directly at each other (phi=0). William >On 23 Mar, 01:12, "WWalker" <william.walker(a)n_o_s_p_a_m.imtek.de> >wrote: >> I dissagree. >> >> Simulation results show that if you add two signals with different >> frequencies and differnt amplitudes, the resultant signal changes in a >> random way as far as a detector is concerned. > >That's the interference. In a steady-state condition. > >Interference is hard to quantify because it is chaotic: Make >the slightest change in any of the initial conditions or >environmental parameters, and it causes a total chance of the >resulting interfernce pattern. > >> If the signal is modulated >> with a carrier and transmitted by a dipole antenna to another dipole >> antenna in the nearfield, the envelope of the received signal arrives >> undistorted, faster than light. > >No, it doesn't. The amateur might have a look at the interference >and get such ideas, but the professional will be aware of >observations of the wave field at oblique angles from the >propagation. > >This is a simple excercise, that can even be simulated: > >Start out with a 2D plane wave propagating in the x direction: > >s(t,x,y) = sin( 2pi f(t - x/c) ) > >Then observe it along a line through (0,0) that intersects the >wavefield at an angle with the x axis, phi. If phi = 0, you >will see an apparent wavelength, lambda', along the line that >equals the free field wavelength lambda = c / f. > >Change the angle of the observation line, and find that >the apparent wavelength equals > >lambda' = lambda / cos(phi) > >Run a simulation of how the observation changes with time, >and find that the *apparent* speed c' of the wave along the >observation line equals > >c' = lambda' f = lambda f / cos (phi) = c / cos(phi). > >It's a ridiculously simple trap, but it seems you >have fallen into it. > >Rune >
From: WWalker on 23 Mar 2010 06:53 Rune, Critisisms about where the research was done are irrelevant to the discussion and pointless. Lets discuss the ideas. They are the only thing that matter in this discussion. William >On 23 Mar, 02:16, Vladimir Vassilevsky <nos...(a)nowhere.com> wrote: >> Randy Yates wrote: >> > Rune Allnor <all...(a)tele.ntnu.no> writes: >> >> >>[...] >> >>I can guarantee that you will find that the transients >> >>propagate down range with a speed exactly equal to c. >> >> > <chuckle> >> >> It looks like there is more and more of them every day. >> Scarry. > >I don't know if you have looked at the paper he has referred >to a couple of times. He claims that he at some time was >affiliated with NTNU. I am not at all surprised - this kind >of stuff is just what I would expect from that place. > >Once upon a time I asked what the procedure is to hand back >my PhD diplomas etc, as I didn't want more affiliations with >them than absolutely necessary. Cut as many ties as possible. > >It turned out there were no such procedures. So one needs to >be acutely cautious about whose company one seeks - their stain >might last a lifetime. > >Rune >
From: Rune Allnor on 23 Mar 2010 07:38 On 23 Mar, 11:53, "WWalker" <william.walker(a)n_o_s_p_a_m.imtek.de> wrote: > Rune, > > Critisisms about where the research was done are irrelevant to the > discussion and pointless. It is relevant in two respects: - Once you claim affiliations with an institution, you also claim to represent the institution. - You as student is subjected to the standards of the institution where you do your work. What you have presented in this thread is totally consistent with the standards of NTNU. > Lets discuss the ideas. They are the only thing > that matter in this discussion. There are no ideas. Only misconceptions at a level where you ought not to have been admitted to a technical university at all (except, of course, for NTNU) and sloppy investigations where you consistently and, for all I know, deliberately disregard the actual explanations of what you observe. Rune
From: WWalker on 23 Mar 2010 08:40 Rune, No one is interested in your emotional rantings. If you have something intelligent to say about the system in discussion then lets talk. But support your ideas with logic. I have given you logical arguments supporting the superluminal conclusion, which ones can you prove are wrong. If you can't then be quiet. Emotional rantings only make you look foolish. William >On 23 Mar, 11:53, "WWalker" <william.walker(a)n_o_s_p_a_m.imtek.de> >wrote: >> Rune, >> >> Critisisms about where the research was done are irrelevant to the >> discussion and pointless. > >It is relevant in two respects: > >- Once you claim affiliations with an institution, you > also claim to represent the institution. >- You as student is subjected to the standards of the > institution where you do your work. What you have > presented in this thread is totally consistent with > the standards of NTNU. > >> Lets discuss the ideas. They are the only thing >> that matter in this discussion. =A0 > >There are no ideas. Only misconceptions at a level >where you ought not to have been admitted to a technical >university at all (except, of course, for NTNU) and >sloppy investigations where you consistently and, for >all I know, deliberately disregard the actual explanations >of what you observe. > >Rune >
From: Rune Allnor on 23 Mar 2010 09:36
On 23 Mar, 13:40, "WWalker" <william.walker(a)n_o_s_p_a_m.imtek.de> wrote: > Rune, > > No one is interested in your emotional rantings. If you have something > intelligent to say about the system in discussion then lets talk. But > support your ideas with logic. I have given you logical arguments > supporting the superluminal conclusion, which ones can you prove are wrong. What you have showed in this thread, is that you 1) Consistently fail to use the simplest terminology wrt to wave propagation 2) Do not have the faintest clue about data analysis 3) Do not know or understand the implications of the speed of light as an absolute limit in physics 4) Do not know or understand the basics of dipole antennae 5) Do not know or understand how to set up a simulation 6) Do not know or understand how to analyze the data from said simulation 7) Do not know or undesrtand how to criticise the results of said simulation 8) Do not know or understand the basics of information theory ....and those are just the ones I remember off the top of my head. As for fools and proofs - well, it's more than a century since Einstein presented his relativity theory, where the speed of light is established as a fundamental limit in physics. When I say that you ought not to have been admitted as a student to a technical university, it's because anyone who passes a high-school level class in physics should know this, and at least stop and think through their own ideas and arguments once one starts talking about exceeding the speed of light. You have failed blatantly on that point. So if anyone her is a fool, it would be you. Apart from that, it is up to the person that makes the extraordinary claim to argue in his own support. *If* you were to be right, it would mean that anything and everything that is based on Einstein's relativity theory - nuclear weapons and powerplants, cosmogology, the stuff they do at CERN - would turn out to be wrong. By all means - it's up to you to make that claim. Just be prepared to be asked thay *you* prove that your are right. It would take a lot more than a mere simulation you don't know how to do, of stuff you don't know, to convince anyone outside NTNU. Rune |