Signal Freqeuency & polarity collation in a fractal array - versus dish-based, pre-summed analysis.

[Jon Abel]

After researching the idea of creating a high-count element array of small loop antennas to create a radio telescope (1700-1900 elements),  I started looking into how a dish mechanically collects signals - and it appears there might be a more accurate, easier to build method - so a person can collect frequency & polarization collated, in-phase signals.

If A.I. is used to analyze patent 512,340, it appears to be a way to use ONLY 2 wires to wrap & connect 2 interleaved  cone coils in series - to create an array of loop-shaped LC tank circuits - while also maintaining wirelength resonance of the full cone, along with wirelength & LC resonant frequencies of each individual loop antenna.   

From what I understand about dishes - they collect ANY frequency, at ANY phase, and at ANY polarity.   A dish doesn't distinguish these variables.   A dish will simply superimpose (add or sum) all collected signals at the focus, and signal processing is used to collate signals into separate frequencies & separate polarities.

Patent 512,340 apparently has the ability to express both these collation tasks naturally - based on the geometry of a recursive (fractal) loop array - before any summation or collection is performed by an SDR.    

Distinguishing 2 polarizations does indeed mean wrapping a 2nd interleaved, counter-clockwise-wrapped coil - for every clockwise-wrapped coil on the first interleaved cone coil.   But it doesn't take up any more space.   

This also means considering a variable that isn't mentioned in the patent - setting the slant-height equal to the circumference of the cone (a constant base angle of 80.8421501 degrees) - which causes single wavelength termination from any loop in the array - to collect at the apex of the cone.   This also removes the need for long or multiple feedlines.   The whole can be wrapped and wired in a very short period of time.    

If your cone is metal - I encourage the use of at least 8-12 slot perforations.   

For reference, my cone slant height is 38.5 inches, the base is 12.25" diameter, and the top hole is 0.25" diameter.    Individual wirelength resonances would calculate to wirelength/2 or 153 Mhz to 7.4 Ghz.    This is perfect for the B220 HamGeek SDR I am using (which also has 2 RX ports for the 2 different polarities).

The goal is to stop having to trust that NRAO & NASA are giving us accurate imaging, and have exclusive access to in-phase signals & distinguish left or right-hand polarized signals before the IQ information is processed in any way. 

My motivations are based on wanting to prove the accurate shape of a cosmic web filament - which I am convinced appears as 2 - 3D AM radio waves that are 180 degrees out of phase.    The resulting "bulge & pinch zones" are observed & documented in Birkeland Currents, so I will be attempting to see if CW filaments also share that "bead necklace" property.   

  

[Marko Cebokli]

Hello Jon!

The dish is of course polarization sensitive, the polarization which it receives, is determined by the feed. There is no such thing as a single non-polarized antenna. Basic physics prevents that. You can make a dual polarization antenna, with two separate outputs (basically two separate antennas, (which can share the same dish)), and then analyze the received polarization by measuring relative amplitudes and phases..

For a plane wave, arriving on the axis (boresight), the dish will add the signal in-phase, that is the idea behind the paraboloidal shape. With an array, you need to add the signals in-phase using (lossy!) cables of precise lengths and power combiners. A dish will do it loss-free for you at no cost, using empty space as the combining system. The advantage of the array is, that you can steer the beam, but only if you provide phase shifters at each element.

Marko Cebokli

05.12.2025 00:45, je Jon Abel napisal

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