How to get envelope from AM signal without phase shift
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From: WWalker on 2 Apr 2010 19:18 Clay, It is true that reflections from the recieving antenna can reflect back to the source antenna and then re-reflect back altering the field received by the receiving antenna. But, in the nearfield the fields decay at 1/r^3 and are very small by the time they re-reflect back (1/r^6) to the receiver dipole. William >On Mar 31, 6:42=A0pm, "WWalker" <william.walker(a)n_o_s_p_a_m.imtek.de> >wrote: >> Hi Clay, >> >> The propagation distance in my 500MHz carrier simulation is 10cm. But the >> distance can be a lot larger for lower carrier frequencies. For example, >> if >> the carrier frequency (fc) is 1MHz (typical AM radio) then the optimum >> propagation distance is 300m (1/6 carrier wavelength) and the envelope >> will >> arrive 80ns earlier than a light speed (propagating envelope (0.08/fc). >> For >> lower carrier frequencies, even larger distances and larger light speed >> time differences are possible. >> >> In terms of quantum mechanics I think the following might be happening in >> this system. If a photon is created a t=3D0 then as it propagates, becaus= >e of >> the uncertainty principle, the uncertainty of the velocity of the photon = >is >> much larger than c in the nearfield and much less than c in the farfield. >> Which means the photon can be much faster than light in the nearfield but >> reduces to the speed of light as it propagates into the farfield. Below i= >s >> the argument that shows this. >> >> Lets calculate the uncertainty of the velocity of a photon that propagate= >s >> one wavelength after it is created: According to the Heisenberg uncertain= >ty >> principle, the relation between the uncertainty in Energy (dE) and the >> uncertainty in time (dt) is: dE*dt >=3D h. The time for a photon to cross= > one >> wavelength distance is: dt =3D lambda/c. Since dE =3D h*df and df=3Ddv/la= >mbda >> then dE*dt=3Dh*dv/c, but dE*dt <=3D h =A0 therefore: =A0dv >=3D c >> For smaller distances the uncertianty will be greater and for larger >> distances the uncertainty will be much smaller. >> >> William >> >> >> >> >> >> >On Mar 29, 12:18=3DA0pm, "WWalker" <william.walker(a)n_o_s_p_a_m.imtek.de> >> >wrote: >> >> Jerry, >> >> >> The speed of light is a corner stone in physics and if it is not a >> consta=3D >> >nt >> >> then many of our theories in physics will be affected. There may be >> direc=3D >> >t >> >> practical uses as well, but I just guessing: improving accuracy of hig= >h >> >> speed doppler radar, speeding up communication to spacecraft where tim= >e >> >> delays are problematic, increasing speed of computers when they are >> >> eventually limited by light speed delays etc. As I said, these are onl= >y >> >> 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: >> >> >> > =3DA0 ... >> >> >> >> 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 advanc= >e >> >> >*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. =3DA0 =3DA0.. Albert Szent-Gyorgi >> >> >- Hide quoted text - >> >> >> - Show quoted text - >> >> >Hello William, >> >> >I suggest you 1st study the EPR paradox and then look up Bell's >> >theorem and see how it applies to Relativity. You are not going to get >> >information over any significant distance with superluminal speed. >> >Sure there is a probability that a particle will travel faster than >> >light for a short distance (say for example across the nucleus of an >> >atom about 10^-14 to 10^-15 meters) but when you start to add up all >> >of the paths in a Feynman diagram, you will see the probability of it >> >happening across a room is not even likely in a time period of the age >> >of the Universe. >> >> >Clay- Hide quoted text - >> >> - Show quoted text - > >Your photons are also influenced by all of the electrons in the >antenna, so you can't treat it them like they are independent items. >Your transmitting and receiving antennas are highly coupled and the >transmission from your antenna has an extra delay compared to when you >are transmitting to empty free space. When you include this delay, I'm >sure you will see your signal input into the tx's coax cable will not >arrive at the rx's coax cable with superluminal speed. > >This reminds of a case two years ago where I met a guy who claimed to >have a machine that created more energy out than he put in. He >"verified" this by 1st measuring the amount of power going into the >the machine. Then he measured the power out by putting a load on it. >Then he concluded he got more power out than he put in. The problem >was he needed to measure the power going it to the maching when it was >loaded. Once this was done, it was clearly observed that the power out >was less than the power in. His investors were not happy! You can >google "Sprain Motor" if you want to know about that particular >machine. > >Now think about the loading your receive antenna puts on to the >transmitting antenna. This will cause an extra delay compared to when >there is no loading on the tx antenna. > >Clay > > >
From: robert bristow-johnson on 3 Apr 2010 01:44 On Apr 2, 5:45 pm, Eric Jacobsen <eric.jacob...(a)ieee.org> wrote: > > The point is that ANY bandlimited signal, regardless of how much > 'information' is in it, can't be too "regardless". the amount of information that can be carried by the signal has something to do with how bandlimited it is (and how much time is spent transferring the signal). > can be predicted by practical processes (e.g., a > filter with negative group delay) in a manner that looks exactly like > the phase advance you're seeing. You claim it reveals accelerated > propagation, but it is more easily explained by mere bandlimited > prediction. i think this is exactly what the issue is about. and William, i think you need to separate the concepts of an arbitrary bandlimited envelope vs. a "group" (in group delay or group velocity) where a delay of 7/8 group cycle appears to be an advancement of 1/8 cycle. But William, if you are generating a modulating signal out of attaching a random bit to the amplitude of a "causal" sinc (a delayed and truncated sinc-like function), I can't possibly see how the determination of whether the pulse had a +1 or -1 scaling it before the random bit is actually generated. You don't think there is the slight possibility of crankery in your theory, do you? What do they say on sci.physics.research about it? r b-j
From: Clay on 5 Apr 2010 11:32 On Apr 2, 7:18 pm, "WWalker" <william.walker(a)n_o_s_p_a_m.imtek.de> wrote: > Clay, > > It is true that reflections from the recieving antenna can reflect back to > the source antenna and then re-reflect back altering the field received by > the receiving antenna. But, in the nearfield the fields decay at 1/r^3 and > are very small by the time they re-reflect back (1/r^6) to the receiver > dipole. > > William > > > > > > >On Mar 31, 6:42=A0pm, "WWalker" <william.walker(a)n_o_s_p_a_m.imtek.de> > >wrote: > >> Hi Clay, > > >> The propagation distance in my 500MHz carrier simulation is 10cm. But > the > >> distance can be a lot larger for lower carrier frequencies. For > example, > >> if > >> the carrier frequency (fc) is 1MHz (typical AM radio) then the optimum > >> propagation distance is 300m (1/6 carrier wavelength) and the envelope > >> will > >> arrive 80ns earlier than a light speed (propagating envelope (0.08/fc).. > >> For > >> lower carrier frequencies, even larger distances and larger light speed > >> time differences are possible. > > >> In terms of quantum mechanics I think the following might be happening > in > >> this system. If a photon is created a t=3D0 then as it propagates, > becaus= > >e of > >> the uncertainty principle, the uncertainty of the velocity of the photon > = > >is > >> much larger than c in the nearfield and much less than c in the > farfield. > >> Which means the photon can be much faster than light in the nearfield > but > >> reduces to the speed of light as it propagates into the farfield. Below > i= > >s > >> the argument that shows this. > > >> Lets calculate the uncertainty of the velocity of a photon that > propagate= > >s > >> one wavelength after it is created: According to the Heisenberg > uncertain= > >ty > >> principle, the relation between the uncertainty in Energy (dE) and the > >> uncertainty in time (dt) is: dE*dt >=3D h. The time for a photon to > cross= > > one > >> wavelength distance is: dt =3D lambda/c. Since dE =3D h*df and > df=3Ddv/la= > >mbda > >> then dE*dt=3Dh*dv/c, but dE*dt <=3D h =A0 therefore: =A0dv >=3D c > >> For smaller distances the uncertianty will be greater and for larger > >> distances the uncertainty will be much smaller. > > >> William > > >> >On Mar 29, 12:18=3DA0pm, "WWalker" > > <william.walker(a)n_o_s_p_a_m.imtek.de> > > > > >> >wrote: > >> >> Jerry, > > >> >> The speed of light is a corner stone in physics and if it is not a > >> consta=3D > >> >nt > >> >> then many of our theories in physics will be affected. There may be > >> direc=3D > >> >t > >> >> practical uses as well, but I just guessing: improving accuracy of > hig= > >h > >> >> speed doppler radar, speeding up communication to spacecraft where > tim= > >e > >> >> delays are problematic, increasing speed of computers when they are > >> >> eventually limited by light speed delays etc. As I said, these are > onl= > >y > >> >> 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: > > >> >> > =3DA0 ... > > >> >> >> 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 > advanc= > >e > >> >> >*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. =3DA0 =3DA0.. Albert Szent-Gyorgi > >> >> >- Hide quoted text - > > >> >> - Show quoted text - > > >> >Hello William, > > >> >I suggest you 1st study the EPR paradox and then look up Bell's > >> >theorem and see how it applies to Relativity. You are not going to get > >> >information over any significant distance with superluminal speed. > >> >Sure there is a probability that a particle will travel faster than > >> >light for a short distance (say for example across the nucleus of an > >> >atom about 10^-14 to 10^-15 meters) but when you start to add up all > >> >of the paths in a Feynman diagram, you will see the probability of it > >> >happening across a room is not even likely in a time period of the age > >> >of the Universe. > > >> >Clay- Hide quoted text - > > >> - Show quoted text - > > >Your photons are also influenced by all of the electrons in the > >antenna, so you can't treat it them like they are independent items. > >Your transmitting and receiving antennas are highly coupled and the > >transmission from your antenna has an extra delay compared to when you > >are transmitting to empty free space. When you include this delay, I'm > >sure you will see your signal input into the tx's coax cable will not > >arrive at the rx's coax cable with superluminal speed. > > >This reminds of a case two years ago where I met a guy who claimed to > >have a machine that created more energy out than he put in. He > >"verified" this by 1st measuring the amount of power going into the > >the machine. Then he measured the power out by putting a load on it. > >Then he concluded he got more power out than he put in. The problem > >was he needed to measure the power going it to the maching when it was > >loaded. Once this was done, it was clearly observed that the power out > >was less than the power in. His investors were not happy! You can > >google "Sprain Motor" if you want to know about that particular > >machine. > > >Now think about the loading your receive antenna puts on to the > >transmitting antenna. This will cause an extra delay compared to when > >there is no loading on the tx antenna. > > >Clay- Hide quoted text - > > - Show quoted text -- Hide quoted text - > > - Show quoted text - Have you actually measured to see if the reflections are small or are you just inferring that they are from theory? Clay
From: steveu on 5 Apr 2010 12:42 >This reminds of a case two years ago where I met a guy who claimed to >have a machine that created more energy out than he put in. He >"verified" this by 1st measuring the amount of power going into the >the machine. Then he measured the power out by putting a load on it. >Then he concluded he got more power out than he put in. The problem >was he needed to measure the power going it to the maching when it was >loaded. Once this was done, it was clearly observed that the power out >was less than the power in. His investors were not happy! You can >google "Sprain Motor" if you want to know about that particular >machine. He claimed to create energy out of nothing, without some profound physics to support it, and actually got investors? Was Sprain his name, or was it Barnum? Steve
From: robert bristow-johnson on 5 Apr 2010 13:11
On Apr 5, 12:42 pm, "steveu" <steveu(a)n_o_s_p_a_m.coppice.org> wrote: > >This reminds of a case two years ago where I met a guy who claimed to > >have a machine that created more energy out than he put in. He > >"verified" this by 1st measuring the amount of power going into the > >the machine. Then he measured the power out by putting a load on it. > >Then he concluded he got more power out than he put in. The problem > >was he needed to measure the power going it to the maching when it was > >loaded. Once this was done, it was clearly observed that the power out > >was less than the power in. His investors were not happy! You can > >google "Sprain Motor" if you want to know about that particular > >machine. > > He claimed to create energy out of nothing, without some profound physics > to support it, and actually got investors? Was Sprain his name, or was it > Barnum? back in 2002, there was a company called ZeoSync that evidently got investors, had a splashy web-site, that claimed to "have discovered a way to shrink virtually any digital file to a hundredth of its size-- and then restore the file to its original size without error." http://news.cnet.com/The-quest-for-near-perfect-compression/2100-1023_3-839851.html there were other companies (banks) with investors that believed that they could make money providing "Liar Loans". Barnum is alive an well, unfortunately, in many forms and persons. r b-j |