FRB 121102 Spectral Analysis of "Doppler Shift Dip in the EM"

[ryan walsh]

I have here a Spectral plot with the Waveform Overlay onto it.

I am presenting a Theory of Rudimentary Frequency Telemetry

I Examine the waveform Signature Up close, An Have spotted what appears to be a Secondary Line of Sight Signal pertruding the FRB dispersion sweep

At a Precise Time in Frequency. 

At 1:44, You will see the Plot- What Appears to be a Electromagnetic Dip/Gap

And A Very Thin Straight Signal perpendicular to the FRB

https://www.youtube.com/watch?v=f3uQDDppwGw&ab_channel=ryanwalsh

As We already know FRB is Frequency an Time. That my Theory is That this could be a Form of Percise Frequency Denotation

Meaning it could be pin pointing a Certain Frequency it is Broadcasting on. And that

3 Other FRBs that I have looked at the Archive Found here. Had Similar instances 

(Its reoccuring)

https://dataverse.harvard.edu/dataset.xhtml?persistentId=doi:10.7910/DVN/QSWJE6

Input is Welcome!

Ryan

[Michiel Klaassen]

Hi Ryan,

Yes FRB's are interesting to do research on.

There is no consensus yet how these are generated. The signal itself is generated on all frequencies at thesame time.

It is like the generation of the broad band E.M. radiation of a lightning strike.

On high frequencies you hear the crackling noise in the radio, but for the low generated frequencies the story is longer.

The low freq signals can be trapped in the earth magnetic field and start traveling outward into space, along the way, the lower part of these frequencies are delayed more then the higher parts (dispersion). When they travel further into the earth atmosphere again they arrive on another continent, where they can be picked up by the receiver.

The fun part is that you need no real receiver; it can be captured by a standard audio amplifier.

Just plug in a long wire into the mic input of your PC card, be patient and record.

see

https://en.wikipedia.org/wiki/Whistler_(radio)

FRB's are recorded between 100MHz and 2GHz. So now you need a real radio receiver, because you cannot hear these frequencies directly. 

Not only that, but also because the frequency range of the signal can be 10's of MHz wide.

So, to make it audible, you have to subtract a frequency from the original (a mixer), and then compress the broad band range into an audio range.

The resulting audio product gives an impression of the received chirp. 

The original signal can be restored by aligning the chirp to form one pulse.

The correction factor to align that is called de-dispersion correction and the value gives an indication of the interstellar density. This value is so high that it cannot be caused by the 'gas'  in our own milky way galaxy alone; so it must be coming from farther away.

When you look at the width of the original pulse (eg 2ms), you must conclude that the size of the radio source must be 3e8 m/s*2e-3 s=6e5m= 600km maximum.

I imagine two magnetars (magnetic collapsed stars) scoff at each other regularly, where the cone of radiation is sometimes directed towards us.

But honestly I have no idea what to think of your theory.

Regards,

Michiel

parac.eu

Op zo 21 mrt. 2021 om 13:13 schreef ryan walsh <rwdesi...@gmail.com>:

--
--
You received this message because you are subscribed to the Google
Groups "Society of Amateur Radio Astronomers" group.
To post to this group, send email to sara...@googlegroups.com
To unsubscribe from this group, send email to
sara-list-...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/sara-list?hl=en
---
You received this message because you are subscribed to the Google Groups "Society of Amateur Radio Astronomers" group.
To unsubscribe from this group and stop receiving emails from it, send an email to sara-list+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/sara-list/df8d3c6f-4d8d-42d0-87de-1219f7dfb189n%40googlegroups.com.

[Larry Mayfield]

Michiel,

You have answered a couple of my questions in this post! One was the frequencies in an FRB.   I have been wondering about the power needed to generate the chirp with all of the frequencies involved and whether or not the signal is omnidirectionsal and the received piece at the earth bound ‘scope is just a teensy part of the very large signal. And when distance and shifting is included what the total broadcast power might be. The Signal I saw on one of your recent  posts, I think it was, showed a very fast rise time followed by a very short decay time with it being over in about 4 ms.  I may have misinterpreted the chart, but still the question arises.. just how much energy does it take to make that signal?  And if the frequency(s) with the highest power are identified it might lead to assumptions on the what is causing them?  Like maybe a gazillion megaton neutron weapon going off? With my tongue firmly in my cheek, maybe Darth Vader and his planet buster is at work somewhere in the universe…

 

In any case, I appreciate your help along the way for us noobs (and I am  one of the biggest, oldest and likely the dumbest, noobs, lol)!   

 

Larry

Pahrump, nv

To view this discussion on the web visit https://groups.google.com/d/msgid/sara-list/CAABBjRCJOt4c62e5k4rS%2Bo0oMbPgVjKbgtSPC3ZgRfciKxf7iQ%40mail.gmail.com.

[ryan walsh]

Its Not happening in the High Frequency, not the Low Frequency. Near the Middle of FRB.

The Gap is always occurring at the Beginning of the Attack pulse, in this FRB and others as well! Same Characteristics. 

Im just wondering if this is a Clipping Problem which would cause distortion

Clipping occurs when you record at too high a level.

Just as when a loudspeaker is pushed beyond its physical limitations, a digital system can be overloaded at the input stage to the point of clipping. When a signal reaches 0 dBFS (full-scale) on a meter, we’ve run out of headroom and potentially into digital clipping issues

[ryan walsh]

I did a Example of how you would figure out the Dip/Gap Frequency As it relates to Frequency and Time

On Sunday, March 21, 2021 at 10:23:16 AM UTC-7 Lawrence E. Mayfield wrote:

[Lester Veenstra]

Monitor the “percent time in  clip”.   That is the number of all 1’s or all zeros out of the A/D per unit time divided by the number of samples per unit time. 

For white noise like inputs, the analog input  level should such to produce 10E-5 to 10E-6 PTIC.

 

Lester B Veenstra  K1YCM  MØYCM  W8YCM   6Y6Y

les...@veenstras.com

 

452 Stable Ln (HC84 RFD USPS Mail)

Keyser WV 26726

 

GPS: 39.336826 N  78.982287 W (Google)

GPS: 39.33682 N  78.9823741 W (GPSDO)

 

 

Telephones:

Home:                     +1-304-289-6057

US cell                    +1-304-790-9192

Jamaica cell:           +1-876-456-8898

To view this discussion on the web visit https://groups.google.com/d/msgid/sara-list/6de42c66-a3ca-4d57-bda8-d3f183f1fbc4n%40googlegroups.com.

[ryan walsh]

All This sounds Chinese To me, I dont Understand it.

I really Only just do waveform analysis and Spectral plots of space sounds. Files Generated and hosted on many websites.

I only Know how to pick up local AM FM stations on a SDR. Im no Radio astronomer by any means.

I only Found something from this data Thats worth Investigating and showing off.

If anyone would like to contribute to this strange annotation please do- I would Love for some Good answer to this mystery I uncovered, 

[ryan walsh]

From my understanding to figure something like this out you would need to understand the python programming toolset for FRBs

I am in no way programmer- 

On Sunday, March 21, 2021 at 1:00:04 PM UTC-7 m0...@veenstras.com wrote:

[Michiel Klaassen]

Hi Ryan,

The frequency you are pointing at is 1.35GHz; you cannot hear that.

The demo is a 'sonification' of the FRB; a way of explaining the principle.

see also

https://www.youtube.com/watch?v=XBEQXgUyR2c

You have to think the vertical axis as rows of buckets holding energy or power, indicated by  s-meter reading.  

The energy is collected from a small range of frequencies; the signals are "rectified" and averaged.

They are not sines anymore.

When the rows of buckets are shifted in the correct way, then the contents of the buckets can be added vertically and the sum bucket row with the highest contents wins, it gives the original pulse form.

    

To explain some more;

The original signal is just noise; when you display the mixed down signal on a scope you see nothing; only noise.

Now when you take a piece of that signal and perform FFT (that is splitting the signal into differentfrequency bands) then you do not see sines anymore but squared sines or power. When the signal is large enough, then you see peaks in the power line.

Those power peaks are shifted from one frequency band compared to the next.

So to me it looks like they took a digital dispersed  frb and multiplied that with a chirp audio tone.

I will see if I can do that also with my frb simulation setup.

Regards

Michiel

parac.eu

Op zo 21 mrt. 2021 om 23:06 schreef ryan walsh <rwdesi...@gmail.com>:

To view this discussion on the web visit https://groups.google.com/d/msgid/sara-list/fb9bb372-dd97-403c-93d7-69dd3267fd5bn%40googlegroups.com.

[ryan walsh]

"The frequency you are pointing at is 1.35GHz; you cannot hear that."

That was just a Example Of Freq and Time, it is not from the same FRB im showcasing. Its only to demonstrate my concept theory

I already know the Rows of buckets. 

We done the analysis and This particular file shows 31 pulses from High Freq to Low Freq

See this File here

https://www.youtube.com/watch?v=LU0BAfj4O24&ab_channel=ryanwalsh

But First we Removed the Noise and Cleaned Smoothed the Frequency Bands. 

We Done a FFT plot too- And Showing many of the different Frequency Bands. To Demonstrate the entirety of those Frequencies bands

After Which we performed a Phase Lock Loop on the Signal. And it Detected a Signal

Applying Amplitude demodulation seemed successful too.

We produced interesting Audio results from this.

We Found within the audio the Sound is Also Repeating, and different sets of repeating

I could also provide the website Links to convert the FRB into Wav. for sonification if you have trouble finding it. 

------

This is definitely not for the Faint of Heart so proceed with caution while listening ..

https://www.youtube.com/watch?v=ZhxqUZ7MyoM&ab_channel=ryanwalsh

[ryan walsh]

Some Simple Noise Reduction calibration per FRB showed many many many various wavelengths. Very Densely Populated Wavelengths infact

Only way to really Hear them all was to Stretch the file according

See Some samples below

On Monday, March 22, 2021 at 2:42:22 AM UTC-7 vmin...@gmail.com wrote:

[ryan walsh]

One Intresting thing I though was. What if we only cut and paste the Chirp 

And to Spectral experiments and demodulation with that. And we could see closer of the FRB

rather it being something distant observed at

[ryan walsh]

Also Just Regarding the Gap/Dip I discovered

I used Audacity and applied a Inverse on the File. And Now That Dip/Gab Has become the Strongest Crest Amplitude out of the dispersion

More interesting the other pulses showed some interesting characteristics also

excuse the bad writing it was done with mouse-

[ryan walsh]

We been trying to suggest that the FRB Gap/Dip 

Is actually the Carrier Signal

[Lester Veenstra]

I am not familiar with the FRBs but to look at (calculate) the PTIC you must be able to look at the raw values coming out of the ADC.   Can you see these?

To view this discussion on the web visit https://groups.google.com/d/msgid/sara-list/fb9bb372-dd97-403c-93d7-69dd3267fd5bn%40googlegroups.com.

[Lester Veenstra]

I agree, you probably do not have the tools to calculate PTIC.  Too look at (calculate) the PTIC you must be able to look at the raw values coming out of the ADC. 

To view this discussion on the web visit https://groups.google.com/d/msgid/sara-list/145cec38-b3ca-4c7c-aac4-b08ab133f7bbn%40googlegroups.com.

[ryan walsh]

It Just take a Eye for Detail to observe those Dip/Gap

Im not saying im Right or anything

Just tossing my 2 cents about it

[ryan walsh]

Im Just Putting forth Public knowledge of the Existence of a Damped Sine wave Pulse that has A Dip/Gap in its Attack 

Should anyone here further explore this- They may come to better understand the signal. 

One must look at the signal close up in order to make the comparison with the other Damped pulses. 

Whats Causing it? Why does it persist in the Beginning of the Attack? Why does the spectral in conjunction with the Waveform Show a Vertical EM build up?

I can Only Assume things. But not withstanding it could be due to instrumentation 

Should anyone Care to explore this phenomenon. Its a lot of work. 

But none the less it does exist. And It takes a Eye for Detail to observe those defects

On Tuesday, March 23, 2021 at 7:21:32 AM UTC-7 m0...@veenstras.com wrote:

[Michiel Klaassen]

Hi Ryan.

As I said earlier; I think that it is a sonified step curve to better understand the FRB.

As my wife always says; "men only want one thing"; and yes indeed I always want to be right.

So, if you want, write a mail to the researchers and ask them how the signal has been composed.

I love to be right, but I am also curious why I am wrong.

Regards

Michiel

parac.eu

Op di 23 mrt. 2021 om 15:32 schreef ryan walsh <youareth...@gmail.com>:

To view this discussion on the web visit https://groups.google.com/d/msgid/sara-list/e65398ec-f5bd-4880-ac59-d5a95d76a03bn%40googlegroups.com.

[ryan walsh]

its all in the github how its composed big tutorial on it. I have no technical means to understand python programming

researchers are far to busy to give a answer

That's Why I come Here- Armatures maybe more open or if someone is working on something relative.

If this is not your cup of tea- don't have to drink it 

Regards

[ryan walsh]