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![]() Hi Art Thanks for taking your time to direct me to some very complex thinking. But, I'm a rather simple guy who isnt well educated. You apparently expect a "just regular guy" like me to understand the ccomplex convoluted theoretical stuff that you write about. When I did work as an antenna design engineer, years ago, I saw some of my buddies working on the distribution of energy across apertures in an effort to shape beams. One of their considerations was to decrease the power to the elements as they were more distant from the center of the array. I remember reading that when the power is tapered to provide a distribution about equivalent to a Gaussian Distribution, the side lobes were minimal. I really enjoy thinking about real antenna construction projects. but, when it gets to the Maxwell's Equation kind of analysis, I get lost. I dont even know what a Vector is. You may have the wrong impression about me, Art, I'm an old guy who wants to have fun with antennas. It isnt necessary for you to tell me to "get back to basics". I dont have interest in the "basics" you refer to. Is it possible for you to tell us (me) what you are referring to without referring to Vectors, Gauss's law, Lorentz, "Nagi", and even elementary calculus? Frankly, Art, you confuse me when you write such scholarly paragraphs. You and I are so far removed from each other intellectually that I can never keep up with your texts. Jerry "art" wrote in message ups.com... Jerry, get back to basics and look up a conservative field relative to Gaussian law. Step 1 It is a group of electric charges with an addition vector of zero. So move backwards and remove that vector if you wish and you have a gaussian field of electrical charges which in the case of a bunch of resonant elements can be seen as all positive or all negative charges and we also know that Gaussian law is valid even for enclosed charges in motion. Step 2 The vector that we removed is known as curl but at this time nit has no valu is the samee tho the vector direction is known. Step 3 Faraday's law of Induced electromotive force. This is somewhat opposite to the consevative field in terms of rotation but in relative terms it where the consevative field is revolving around a magnetic field ( hopefully you can visualise this) So we have a charge q in an element of length ds, which element, at the instant considered has velocity u,experiences a force. Now I know some have difficulty with what I said earlier with respect to adding " at an instant of time) to Gausses law which is the same length of time referred to above as " at the instant considered " Gtep 4 We then examine Lorentz equation which refers to an induced electric field which is present when, for example the magnetic field is changing with time such that v1 = 1/q integral F.ds. You can now see that any CONSERVATIVE force that might be included in F would integrate to zero thus ommiting any electrostatic field that might be present Note again faradays law, it is valid regardloess of the nature of the factor or factors responsible for change in magnetic flux. So now the overview of the cluster of resonant elements projected a conservative field with a magnetic vector of zero reflecting" an instant of time" with respect to resonant elements and where the magnetic field will provide motion to the electrostatic field where all charges will exibit the same direction of charge and will change in unison Now no amount of writing will get you to understand this flow of concept if you are not willing to have an open mind or think around something that at the present time you fail to understand and are not willing to rethink thing, possibly in a different way than I presented it. If you are so inclined you can go back further in history and play with the 4 vertical array of elements formed by Nagi to obtain possible insights since he also worked with an array of vertical elements all of which were resonant. His work has been rechecked via Matlab and found to be correct so you have a viable path to follow if you have a modicom of interest in this new concept. It must be noted that the above is only a partial description of the concept because I have yet to add a detuned element for directional purposes for the radiation field. There is nothing more that I can add that will persuade you to follow thru with this concept so I believe I have now reached the Rubicon with respect to this vision of mine. If you can't understand it now put it down to me not being smart enough to explain clearly electromagnetics to those skilled in the art which I am now finding to be a hopeless task at least here in the U.S. unless one can read it in a book and memorise it so one can pass an exam.. Art Jerry Martes wrote: "JIMMIE" wrote in message ups.com... Dave wrote: "art" wrote in message ups.com... In the thread Rain static I referred to a closed surface which is clearly defined by Gauss's law. Gauss's law doesn't define a surface, the surface is any arbitrary surface surrounding a charge. Let us now look at a time vary field applied to a dielectric. I fht efield is applied for the shortest of time the charges will stay on the surface. If time is longer than the shortest space of time you make it sound like there is some 'shortest' time where charges won't move. this is not true. no matter how short you make the time it will move the charges. then charges will openetrate the closed surface. If the surface is an insulator type then it takes a long while to penetrate but if the surface Here you mix up 'surface' and 'surface'. the gauss's law 'surface' is a mathematically useful construction around a charge, it does not have any charge 'on' it, nor is there any 'penetration' of it by charge in gauss's law. it is strictly a non-material thing that is used only for calculation purposes. is a good conductor then the charges will penetrate very quickly so we can associate the time constant of penetration to the subject of skin depth. If we are to associate the time varying field to a gaussian field you have yet to define a 'gaussian field'. gauss's law applies to electric fields and their relation to charges. all the excess charges must be on the surface by law. only in a 'perfect' conductor. dielectrics and 'empty' space can have distributed charges throughout. Or in other words the time evolved must be shorter than the time required to begin penetration. huh? it just goes down hill from here. write some equations, do some drawings, publish a manuscript. all the rest is empty handwaving based on incorrect assumptions and missing definitions. Thus for a short space of time all charges are on the surface and the charges have a magnhe radiating eneetic and electric field vectors. Just having charges is not enough to convert to a gaussian field in that a gaussian field must be in equilibrium thus a cluster of elements must have the direction of the surface charges change in unison. For a cluster of elements to do this they must all be resonant such that the charges reach the ends of the elements at the same time. Resonance of an element is determined by its diameter and its length and because it is coupled to other elements in the cluster the coupling must be taken into account to secure resonance of not only the individual elements but of the cluster as a whole. When this is accomplished the charges on the surface of the closed volume are in equilibrium but onty for that shortest of short time and where that time is added to the gaussian formulae for the transition to be complete. For the Gaussian field or volume we can say the energy inside the gaussian field is equal to that supplied by flux to the outside of the border and remember the flux inside consists of magnetic and electric vectoirs. We now can say that in a moment of time the flux produced from each element that breaches the border in summation with the other elements is equal to the radiating field outside of the border when each element energy makes the transmittion. Thus the summation of each of the clustered elements individual energy when the vectors are given a value must equal the flux on the outside of the border that produces radiation. We also know that if we have a cluster of elements that are clustered together we can obtain radiation by just applying a time varing field to just one of the elements and by virtue of intercoupling all the radiating energy will leave the near field. Thus we have two different methods of determining the value of the radiated field ! radiation from the clustered within a Gaussian field and 2 radiation from an array of coupled elements Since the elements within the cluster are all of the same "Q'" the determination of all factors in the resulting equation are simplified to Ohms law and where the laborious coupling calculations are omitted. The above describes in first principles as to how a Gaussian field in a short space of time can be equated to a radiating cluster using existing laws of the masters which also embraces NEC code. Now many have said I have no understanding of radiation concepts so go ahead and tear this apart and have a merry Xmas doing it Art Unwin KB9MZ..........XG It appears Art has picked up some phrases haphazardly and is trying to apply them to antennas some how, If I remember correctly doesnt Gaussian field apply to statistical distribution. Been a long time since I had statistical analysis back in the early 70s but I think this is also refered to as a "normal distribution". Hi Jimmy By my standards, you are *Right On* on all you wrote. I'm pretty sure Gaussian distribution of power across a radiating plane results (theoretically) in zero side lobes, That is also a very poor distribution when gain is a goal. I think the term Normal is synonymous with Gaussian when referring to aperture distribution. Jerry |