How to get envelope from AM signal without phase shift
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From: Rune Allnor on 29 Mar 2010 09:52 On 28 Mar, 22:13, Eric Jacobsen <eric.jacob...(a)ieee.org> wrote: > Perhaps what you think you're demonstrating is the mechanism by which > the system achieves the same sort of bandlimited prediction experienced > in a negative group delay filter. The guy has done nothing of the sort. What he has done, is to fail Wave Theory 101 and use the *approximate* expression valid in the (distant) far field in the immediate vicinity of the monopoles. A freshman blunder. If this amateur WW goes back to Wave Theory 101 and 1) Actually derives the expressions for the radiating monopole (which include Hankel functions) 2) Applies the trivial superporsition principle with the two monopoles in question 3) Runs the *correct* simulation and not the far field approximation 4) Accounts for trivial interference effects there will be no more dicussions. Somebody suggested that WW is not stupid. Let him (WW) support such a claim by showing that he is able to do the trivial exercise indicated above. Rune
From: WWalker on 29 Mar 2010 11:06 Rune, The transfer function I use in my simulations is well known for the magnetic field component of an electric dipole: (1/r^2)e^(ikr)[ikr-1]. You can look this up in any EM book or look at my paper Eq. 46 were I have derived it from Maxwell Equations, also refer to Eqn 9 in the Sten paper. It is well known and stated clearly in most text books that the model is only valid provided the distance to the observation point is much larger than the dipole length. Since a dipole can be arbitrarily small, this limitation of the model can be satisfied in the nearfield of a dipole. So in summation, the model I use in my simulations is valid in the nearfield, provided the dipole length is much smaller than the distance to the observation point. William >On 28 Mar, 22:13, Eric Jacobsen <eric.jacob...(a)ieee.org> wrote: > >> Perhaps what you think you're demonstrating is the mechanism by which >> the system achieves the same sort of bandlimited prediction experienced >> in a negative group delay filter. > >The guy has done nothing of the sort. What he has done, is to >fail Wave Theory 101 and use the *approximate* expression valid >in the (distant) far field in the immediate vicinity of the >monopoles. A freshman blunder. > >If this amateur WW goes back to Wave Theory 101 and > >1) Actually derives the expressions for the radiating monopole > (which include Hankel functions) >2) Applies the trivial superporsition principle with the two > monopoles in question >3) Runs the *correct* simulation and not the far field > approximation >4) Accounts for trivial interference effects > >there will be no more dicussions. Somebody suggested that >WW is not stupid. Let him (WW) support such a claim by showing >that he is able to do the trivial exercise indicated above. > >Rune >
From: WWalker on 29 Mar 2010 11:42 Eric, Could you elaboate on your comment below. I think we need to agree on the definition of information in regards to the LPF pulsed carrier simulation. How does your comment refute my argument presented again below? >I suppose you can argue semantics here about what defines the "pulse", Again I claim: "Refering to the Low Pass Filtered Pulse simulation I posted, the simulation clearly shows that if I transmit a pulse, the pulse edge arrives sooner than if it had propagated faster than light. If my detector at the receiving end is a threshold detector which is set to look for anything above the noise level, it will fire earlier than if the pulse had propagated at light speed. In other words, it shows that if I push a button launching the narrowband pulse signal and propagate it via a dipole to a nearfield receiver with the threshold detector, the pressed button will be detected sooner than a light propagated signal. This clearly shows that an action (informaton) in this nearfield dipole system can be detected faster than light. If this is true than I have proven my point that information propagtes faster than light in the nearfield of a dipole." "it does not matter what the reason is. If I have a communication link that allows me to transmit a pulse over a distance faster than a light propagated pulse, then the pulse propagates faster than light. If I use the pulse to denonate a bomb located a distance away, the bomb will explode sooner than if the pulse propagated at the speed of light. This is absolutly true and cannot be argued. The only question is if the dipole simulation demonstrates that a pulse can be detected over a distance faster than light. I think it has. " So if press a button with the same signal characteristics as the LPF pulse, and if I use the above setup to detect the pulse and explode a bomb, the bomb will explode earlier than if the pulse propagated at the speed of light. The pressing of the button (Action) results in the exploding of a bomb (Reaction) faster than light speed. This is clear cause and effect (information) which propagtes faster than light. William >I suppose you can argue semantics here about what defines the "pulse", >On 3/28/2010 11:40 AM, WWalker wrote: >> Eric, >> >> I am sorry to insist, but it does not matter what the reason is. If I have >> a communication link that allows me to transmit a pulse over a distance >> faster than a light propagated pulse, then the pulse propagates faster than >> light. > >I suppose you can argue semantics here about what defines the "pulse", >but understand that "information" is not propagating faster than light >in any of the examples, and neither is energy. This seems to be the key >point that must be understood. A simple small phase advance of a >signal is NOT indicative of information exceeding the speed of light. > >If you just want to claim that the signal has phase advanced and appears >to arrive earlier than expected, that's fine, I don't think anyone will >argue with you there. That's what has led to discussion and study on >this topic in many places. > >> If I use the pulse to denonate a bomb located a distance away, the >> bomb will explode sooner than if the pulse propagated at the speed of >> light. This is absolutly true and cannot be argued. The only question is if >> the dipole simulation demonstrates that a pulse can be detected over a >> distance faster than light. I think it has. > >If you want to wave your hands about the definition of the pulse, sure. > If you want to claim that actual information has been accelerated, >then, no. You've demonstrated something that's been known for a long >time, that bandlimited signals have a predictable quality than can be >exploited. That's not new. > >> The Andor circuit is only phase shifting the signal so that it appears the >> signal outputs before it is sent. The proof is that you can not use the >> circuit to turn itself off before the message was sent, thereby preventing >> the message from being sent in the first place. This is clearly shown in >> Fig. 7. Also note that in my dipole system the pulse always arrives after >> it is sent, not before as in Andor's circuit. > >The relevant part of the argument is that the signal arrives before >expected. Whether the acceleration is due to negative group delay or >phase velocity or some other mathematical arrangement, the point is that >a bandlimited signal can appear to be predicted by fairly simple >processes. The circuit in Andor's example isn't very complicated. The >mechanisms by which the dispersion or phase response is affected in the >near field of an antenna doesn't appear to be out of that realm at all. > The key point is that there is a straightforward explanation that >doesn't involve non-causality or propagation faster than light. > >So when somebody comes along and shows the exact same sort of small >phase advance associated with bandlimited prediction and says, "this >proves propagation faster than c!", it cannot be taken as true by anyone >who knows of the more likely explanation. There is a very large burden >of proof that goes with such a claim, and I haven't seen anything that >would indicate to me a single step past the ordinary explanation. > > >> Figure 2 in the Sten paper is showing the propagation of a pulse in the >> nearfield using the transverse electric field, where I and talking about >> the magnetic field component and my signals always arrive at the detector >> after they are sent, not before. Note the transverse electric field pulse >> in Fig 2b arrives before the signal was sent. This is because the >> transverse field is being created 1/4 wavelength outside the source and >> propagates both back toward the dipole and away from the source. At >> distances larger than the 1/4 wavelength the pulse is seen to propagate >> away from the dipole. If you plot Stens group speed Eq. 18 you can clearly >> see this. Refer my paper Eq. 72, and plot Fig.14. An animation showing this >> is shown in Fig. 20, 21, 23 > >Perhaps what you think you're demonstrating is the mechanism by which >the system achieves the same sort of bandlimited prediction experienced >in a negative group delay filter. Again, that's far, far more >believable than propagation faster than c, especially when it's a known >and understood phenomenon. > >Yet again let me point out that a discontinuity like that shown in >Andor's analysis might be able to be measured through your system. It's >clear you're not trying to show causality, but propagation. So why not >demonstrate the discontinuity propagating faster than c? I'd think it'd >be a good experiment and might reveal something useful about the system. > >I think until you can demonstrate something like that the more likely >explanation of bandlimited prediction would be expected to prevail. > > >-- >Eric Jacobsen >Minister of Algorithms >Abineau Communications >http://www.abineau.com >
From: Rune Allnor on 29 Mar 2010 12:04 On 29 Mar, 17:06, "WWalker" <william.walker(a)n_o_s_p_a_m.imtek.de> wrote: > Rune, > > The transfer function I use in my simulations is well known for the > magnetic field component of an electric dipole: (1/r^2)e^(ikr)[ikr-1]. You > can look this up in any EM book or look at my paper Eq. 46 were I have > derived it from Maxwell Equations, Neither the textbooks nor you have derived anything. You (and the textbooks) refer to tabulated approimation you don't understand how were derived, or the extent of their validity. The key to pinning down the causes of your incompetence is to derive the results from scratch. I have already told you how to do this in a different post. > It is well known and stated clearly in most text books that the model is > only valid provided the distance to the observation point is much larger > than the dipole length. Again: Your problem is that you don't understand the basics. Start with the monople. The results you have "derived" are only valid in the far field of the monoploe (which, of course, you would have known had you *read* my previous posts). Once you understand it fully, you might advance to the dipole. As I said before: Your ego is your problem. There is no point refering or listiong results if you don't contemplate their impact and consequences. You have demonstrated a unique ability *not* to think. You will not get anywhere unless you acknowledge that fact. Rune
From: WWalker on 29 Mar 2010 12:18
Jerry, The speed of light is a corner stone in physics and if it is not a constant then many of our theories in physics will be affected. There may be direct practical uses as well, but I just guessing: improving accuracy of high speed doppler radar, speeding up communication to spacecraft where time delays are problematic, increasing speed of computers when they are eventually limited by light speed delays etc. As I said, these are only guesses, the main effect would be a change in many of our theories in physics, which would eventually lead to new practical uses and technologies. William >Eric Jacobsen wrote: > > ... > >> I think until you can demonstrate something like that the more likely >> explanation of bandlimited prediction would be expected to prevail. > >Even allowing the unlikely possibility that the 6-degree phase advance >*in the near field* represents a real speed increase, and that the >"pulse" in the far field is expected to show no advance at all, What >practical use can this have? > >Jerry >-- >Discovery consists of seeing what everybody has seen, and thinking what >nobody has thought. .. Albert Szent-Gyorgi >����������������������������������������������������������������������� > |