So you're saying that these things could, theoretically, be adapted to
existing radios?

On Mon, May 22, 2017 at 3:40 PM, Chuck McCown <[email protected]> wrote:

> Actually, no processor.  It is all in the antenna.  If a conventional
> antenna is a funnel and you fire vollyballs at it, then the antenna for
> this is an auger that you fire vollyballs that are all on a string like a
> string of beads and they fly through the air in a cork screw orientation.
>
> If the pitch of the auger matches the pitch of the string of balls, you
> are golden.  Otherwise they will bounce off the antenna.
>
> *From:* Lewis Bergman
> *Sent:* Monday, May 22, 2017 2:37 PM
> *To:* [email protected]
> *Subject:* Re: [AFMUG] OAM
>
> If my head stops hurting enough, what I get out of your explanation is
> that the angle and "direction" from center received by the antenna can
> segment the signals. Kind of like staring at a propagation map on a wall.
> Since the antenna has to be in the middle where there is a null it can
> perceive that 0 degrees, although oriented exactly like 180 degrees, is not
> the same signal.
>
> If so I can't imagine what kind of beefy processor it would take to sort
> all that out after the snowplow gets done slicing it up. By the way, if my
> attempt to rephrase your description isn't correct, everybody ignore it and
> don't try to explain it. I think I feel a brain bleed coming on.
>
> On Mon, May 22, 2017 at 10:11 AM Cameron Crum <[email protected]> wrote:
>
>> Oh...in your first post you said "Different numbers of wavelengths can
>> be chopped out of the baloney and joined up as a ring."  I took that to
>> mean different wavelengths, but you meant different multiples of the same
>> wavelength?
>>
>> On Mon, May 22, 2017 at 10:05 AM, Chuck McCown <[email protected]> wrote:
>>
>>> Same frequency.  Different streams of information launched into the
>>> ether all on the same frequency.
>>> But the streams are oriented in space in a way they do not interfere
>>> with each other.
>>>
>>> *From:* Cameron Crum
>>> *Sent:* Monday, May 22, 2017 9:03 AM
>>> *To:* [email protected]
>>> *Subject:* Re: [AFMUG] OAM
>>>
>>> How do you have different wavelengths and not different frequencies? Or
>>> are you referring to frequency as some channel of a certain bandwidth?
>>>
>>> On Mon, May 22, 2017 at 9:35 AM, Chuck McCown <[email protected]> wrote:
>>>
>>>> I finally re-read an IEEE magazine enough times to understand the OAM
>>>> propagation.  (Orbital angular momentum)
>>>>
>>>> If you have missed it, for the past 20 years there have been thousands
>>>> of white papers written on a type of radio signal called OAM.  It looks a
>>>> lot like circular polarization but the interesting thing is that you can
>>>> use the same frequency for multiple streams that do not interfere.  In
>>>> theory an infinite number of streams.
>>>>
>>>> So, here is how I got it explained to myself so that I could understand
>>>> it.
>>>> Using a special antenna, each wave front is launched like a smoke
>>>> ring.  And the wave itself , or integer multiples of the wave are like
>>>> little snippets of string formed into a ring.  That is the smoke ring.  As
>>>> you traverse it around the ring the phase of the smoke changes.  So think
>>>> of it as taking a n-lambda  foot long chunk of the radio signal.  Chop it
>>>> out like a long piece of baloney and join it to its self.  Then set up some
>>>> kind of launcher that can throw these rings of signal at the other end, not
>>>> like a frisbee but like a pie in the face.
>>>>
>>>> Different numbers of wavelengths can be chopped out of the baloney and
>>>> joined up as a ring.  If you have rings from one transmitter made out of
>>>> two wavelengths and rings from a different transmitter of three
>>>> wavelengths, they can all use the same frequencies and they will not
>>>> interfere with each other.
>>>>
>>>> The downside is you have to have some really complicated funky antennas
>>>> at each end and they have to be aimed up perfectly.  The antenna center
>>>> must be in the center of the smoke ring to receive it properly.  If it is
>>>> off to the edge it will not have the clean separation from the other rings
>>>> with different integer multiples.
>>>>
>>>> Should work for very high frequencies over short distances.  Like 10
>>>> GHz on up.  They are doing it with lasers.  I have see the 10 GHz
>>>> antennas.  They look like the internal parts of a rotary snowplow.
>>>>
>>>
>>>
>>
>>
>

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