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Yes I have those reference books but I do not have access to IRE procedings.
My quest was not an easy one and I reflected long as to why the NEC model did not reflect an absolute zero Front to back. On reflection I realised that a straight element in an array is not necessarily the most efficient radiator. Then you have the position that a deformed radiator must have a definite coupling on other elements as shown by Moxon to have a resistive impedance, he used the bending of elements to pursue this. And there are other things to be concerned about such as element diameter change as we move away from the center as well as the element structure that is tubular and not solid which would portray a different aproach with respect to skin resistance. One thing I did look at was the difference in F/B when I went for maximum gain and the change that occured when I went for maximum F/B and I was surprised to see the F/R increase at a large rate and reach its maximum of more than 50 percent improvement ( actually 100 % improvement for the low TOA )at the loss of less than one half db loss in gain because the range of maximum gain was reduced. In retrospect this is not surprising as the frontal lobe became larger in diameter at a lesser percentage rate of what was taken from the rear Hopefully the weather will change soon so I can see exactly what is happening with a full scale array Regards Art "Jerry Martes" wrote in message news:Mf0Yd.43497$uc.34067@trnddc01... Art If your question is "is there any written work that pertains to how gain and sidelobes are related", the answer is Yes. I dont know where back issues of the IRE Proceedings can be found. But, the Proceedings of the Professional Group on Antennas will have so much information on current distribution on a planer array that you may not have enough time left to read it all. The current distribution across an antenna aperature has been studdied very seriously. I am not qualified to discuss phased arrays. I am convinced that max gain will not be acheived with the same current distribution as for minimum side lobes. I realize that you write only "back lobes". But, thats a side lobe at that special angle I am rather simple minded when it comes to phased arrays. I use Referance Data For Radio Engineers as a referance book. It has alot of information on phased arrays. I suspect all the information I have has already been concidered by you. Jerry " wrote in message news:2w_Xd.52445$Ze3.8223@attbi_s51... O.K..O..K Seems like everybody has forgotton the basics of the polygon of forces and other uses of vector so I will go over the basics. At the age of 14 yearsI entered the School of Engineering and Navigation where they hashed things from first principles, Since I had little schooling during those war years it gave me an accelerated course on what I had missed during those schoolless years which meant a lot of homework and I had to work like hell. From the name of the school it was evident that I would get a quick introduction on vectors for forces and navigation . This went as follows: When you swim across a swimming pool then you can swim point to point. If you swim across a river and tried to swim point to point you finish up on the other side but down, stream thus to get to the original point of the endeavor you must swim upstream. If you are a ship or a plane it is obvious that you must have enought fuel to get from point to point so this becomes very important. Thus going back to the river swim you can draw a vector or line that follows the path you took first to cross the river. Since you have units such as time and distance you can draw that line in scalar form. Then you add on to the tail end of the line the journey upstream again in scalar form which will be something less than a 90 degree angle. If you then look back at the point that you started from it becomes obvious that when you swim across stream the angle you must follow is the angle which is shown from the beginning of the triangle to the point that you finished up. Next time you are on a plane look downwards and pick up the flight pattern of small private planes and you will see that their flight path is different from the angle projected by the fuselage All this is in accordance with Newton's law that 'every action has an equal and opposite reaction.' Now look below at my original post to what I said and you will see that I applied a scalar drawing that consisted of many scalae directions in the same way a sailing ship would do if it had to keep changing direction to get to shore. The first vector drawn for an element with known phase and current was drawn which happened to be a vertical line of known length. The next line was then added at the end to reflect the current and phase of the next element chosen and then onto the next element chosen. But this element presented a phase and current that was equal and opposite to the one previously drawn which meant that I was back to the tail end of my first vector chosen ! Thes two elements are termed destructive In fact this happened several times where vectors cancelled each other so we are just left with a singe vector in our scalar drawing .This meant to get back to the point of origin and remembering Newton's law previously alluded to the scalar drawing it represents a vector that is equal to the starting vector drawn, THE SAME PHASE and same CURRENT. Thus the polygon reflects an array where the phase is constant but the currents are ADDITIVE This represents the radiation pattern of a figure eight EXCEPT all the radiation is now to one side of the feed point and comprising of a single and larger circle. All of this reflects exactly what I stated below except I assumed that the pologon phase drawing was already known to all, for which I apologise. With NEC I constructed a model that closely followed this format though the real world did not make elements exactly equal but when I rehashed in my mind the basic priciples the polygon aproach verified that this aproach does give extraordinary front to back/rear figures that gave rise to mistrust of the softwear being used where you may remember that I commented on a model that I made and where the response was that the f/b was to high a point that had troubled me for many a month. Sorry for the long winded response which reflects what I have gone thru with my postings which apparently projected me as a total fool that gave rise to dirisive comments. Now I ask again, is there any written work that pertains to max gain and f to b/rear being on the same frequency? Best regards to all, no hard feelings Art KB9MZ................XG " wrote in message news:dySVd.30807$r55.174@attbi_s52... I have just come to realise that if one drew a polygon of element phases in a array and all elements were 180 degrees to its companion element and excluding the driven element, the max gain and max front to back will occur at the SAME frequency! Until now I was of the understanding that these two max figures could not occur at the same frequency. Is there anything written about this possibility? Regards Art |