locked Very interesting use of WSPR information to solve a long standing mystery #reception #WSPR #bearing


Samuel W7STF
 

Just finished watching a very interesting 60 Minutes Australia episode on YouTube suggesting the final resting place of Flight MH370 in the Indian Ocean might very well be pinpointed through the use of QRP WSPR traffic analysis.

The 60Min episode presenting the work of Richard Godfrey is here: https://youtu.be/Jq-d4Kl8Xh4
73 W7STF Sam


Tom M0LTE
 

On Wed, 23 Feb 2022 at 19:30, Samuel W7STF <sernstfortin@...> wrote:

Just finished watching a very interesting 60 Minutes Australia episode on
YouTube suggesting the final resting place of Flight MH370 in the Indian
Ocean might very well be pinpointed through the use of QRP WSPR traffic
analysis.

The 60Min episode presenting the work of Richard Godfrey is here:
https://youtu.be/Jq-d4Kl8Xh4
73 W7STF Sam






Ron
 

Wow, very interesting indeed.

Ron - KJ5XX

On Wed, Feb 23, 2022, 1:30 PM Samuel W7STF <sernstfortin@...> wrote:

Just finished watching a very interesting 60 Minutes Australia episode on
YouTube suggesting the final resting place of Flight MH370 in the Indian
Ocean might very well be pinpointed through the use of QRP WSPR traffic
analysis.

The 60Min episode presenting the work of Richard Godfrey is here:
https://youtu.be/Jq-d4Kl8Xh4
73 W7STF Sam






Samuel W7STF
 

On Wed, Feb 23, 2022 at 02:45 PM, Tom M0LTE wrote:


Hi Sam

Worth a read
Tom. I appreciate that. I hadn't actually read the paper from his blog. Alas, I am a victim of wanting to believe the idea had merit, and had real potential to help bring closure to the many families who lost loved ones travelling on that flight.
73 W7STF Sam


 

Hi Sam,

There’s been a lot of discussion of this theory in the groups. The consensus is that it will be unlikely. Too much other air traffic across the Indian Ocean creating a high level of noise in the data being analysed – aircraft flutter on signal strengths being reported between two nodes.

Anyhow, WSPR data is a small part of the data this guy is using, so he might come up with something.

73 Phil GM3ZZA

Sent from Mail for Windows

From: Samuel W7STF
Sent: 23 February 2022 19:30
To: main@WSJTX.groups.io
Subject: [WSJTX] Very interesting use of WSPR information to solve a long standing mystery #reception #WSPR #bearing

Just finished watching a very interesting 60 Minutes Australia episode on YouTube suggesting the final resting place of Flight MH370 in the Indian Ocean might very well be pinpointed through the use of QRP WSPR traffic analysis.

The 60Min episode presenting the work of Richard Godfrey is here: https://youtu.be/Jq-d4Kl8Xh4
73 W7STF Sam


Alan <g8lco1@...>
 

Amplitude variation by an aircraft crossing the raypath of a WSPR signal is not detectable as the waves diffract around the aircraft, there is no significant amplitude loss much less than the 1dB SNR steps of WSPR.

However Doppler is different.  A scattered and Doppler shifted signal from  an aircraft would be a clear separate signal above or below the normal signal frequency which could be strong evidence for an aircraft.

 I searched the WSPR database using WSPR.LIVE and WSPR Rocks to find dupes ( duplicated transmissions). Many dupes are "hummers", transmitters that produce mains frequency sidebands that are decoded as separate 50/60 Hz offset sidebands. These stations are easy to list. Then there are people who use multiple receivers and antennas  who produce two or more spots with different SNR's and delta FX's.  These are easily found too. Lastly there are Doppler shifted aircraft reflections. The reflections are Doppler shifted by around  plus /minus 10Hz or so depending on angles and are generally weaker than the direct path signals. From examining very many Doppler signals it is clear that the detection range is at most 20Km for aircraft landing at a local airport and that VERY FEW observers ever log Aircraft Doppler signals at all, those that do are close to airports.

Higher altitude or distant flights do not produce WSPR records, the simple reason is that these signals are extremely weak, way below the detection thresholds to make it into the WSPR Database. An OTH Radar uses Megawatt transmissions from very directional antenna arrays and advanced pulse compression to get 3000Km detection range on a good day. To think that 5W WSPR transmissions could detect distant aircraft is insane.

 If you found the TV show interesting you might find the work of a real expert group even more interesting because they present real evidence and have access to far more information than WSPR records. The flight path was very carefully planned, it exploited weaknesses in ATC procedures and radar coverage. Whoever was the Person In Charge they had expert knowledge of the aircraft's systems, the aircraft battery capacity and many other factors.

Judge for yourself :-

Royal Aeronautical Society Video <https://youtu.be/Qk1CxO9XGyQ>

PDF detailed Summary PDF <MH370-PlausibleTrajectory-CAPTION.pdf (mh370-caption.net)>

Personally I think it very sad that the People who lost loved ones have been given false hope by someone who does not understand RF and has failed to listen to the People who do yet continues to self publicise.

73, Alan G8LCO.


Alan G4ZFQ
 

On 25/02/2022 01:25, Alan (G8LCO) wrote:

However Doppler is different.  A scattered and Doppler shifted signal from  an aircraft would be a clear separate signal above or below the normal signal frequency which could be strong evidence for an aircraft.
Doppler shifted aircraft reflections. The reflections are Doppler shifted by around  plus /minus 10Hz or so depending on angles
And frequency Alan?
10Hz on VHF is often seen but on 20m shift would be much less.
The "clues" of Mr Godfrey are 1Hz "Drift" at the expected time.
Has anyone any data about aircraft Doppler on 20m? It is suggested that the exhaust trail could contribute.

From examining very many Doppler signals it is clear that the detection range is at most 20Km for aircraft landing at a local airport and that VERY FEW observers ever log Aircraft Doppler signals at
I think many can observe them on VHF if they try.
But from 5 Watt HF WSPR at thousands of miles?

To think that 5W WSPR transmissions could detect distant aircraft is insane.
However there have been a few independent tests that claim to confirm the possibility that Mr Godfrey's method could work.
Mr Godfrey is careful to say conditions were good and stable.
I'm sceptical but would like it proven one way or another.

73 Alan G4ZFQ


Ellis Birt (G7SAI)
 

Alan, I agree with you.

The only way to prove (or disprove) Mr Godfrey's work is for there to be independent peer review with newly-gathered data correlated with other position data (ADS-B?).

Even if it does not lead to the location of the plane there may be something to learn from the exercise.

73 de Ellis G7SAI.


Samuel W7STF
 

On Fri, Feb 25, 2022 at 03:13 AM, Alan wrote:


Judge for yourself :-

Royal Aeronautical Society Video < https://youtu.be/Qk1CxO9XGyQ >
I find the video you posted fascinating. Thank you for posting this.
W7STF Sam


Pete Smith
 

Look into it a bit, as has been done, and even us non-tekkies quickly realize how absurd it is to imagine that WSPR at HF could have located an aircraft in a location thousands of kilometers from the participating stations.  It's a little long (19 minutes), but mid-way through <https://www.youtube.com/watch?v=KefDzzDAeew>, HRDX thoroughly demolishes the whole long-range wspr location argument.

73, Pete N4ZR
Check out the new Reverse Beacon Network
web server at<http://beta.reversebeacon.net>.
For spots, please use your favorite
"retail" DX cluster.

On 2/25/2022 8:26 AM, Samuel W7STF wrote:
On Fri, Feb 25, 2022 at 03:13 AM, Alan wrote:

Judge for yourself :-

Royal Aeronautical Society Video< https://youtu.be/Qk1CxO9XGyQ >
I find the video you posted fascinating. Thank you for posting this.
W7STF Sam




Alan <g8lco1@...>
 

Hi Alan,

The Doppler shift depends on the relative velocity and the angles and is also proportional to the frequency. The shifts I gave were the values that are typical on 20m  for aircraft landing or taking off from an Airport. The typical approach speed of an airliner is around 150Kn. If you look at the dupes record from WSPR.LIVE  then click on the highlighted signal the software will show all of the data from that spotter. Shifts of 2-20Hz are probably aircraft reflections. Such  a search shows ALL of the spots recorded.  Of all spotters in the World there is only one station that consistently has many Doppler spots,  ON3URE  close to to Brussels Airport and underneath some very busy lanes.

Higher shifts would be produced by  aircraft at cruising altitude but the signal level is much smaller because the aircraft are much further away. Aircraft reflections from WSPR are inevitably weak, the very small WSPR signal induces a current into the aircraft structure which is then re-radiated in all directions, a further reduction of a weak signal which sends high reflections below WSPR detectability. The normal spotter SNR range at HF is around  +20 to -30 dB so the very maximum loss could be -50dB, unfortunately the additional loss from  aircraft scatter at 27,000 - 40,000 ft exceeds  the 50dB additional loss, the Doppler shifted spots can be linked to Flight Radar 24 plots of aircraft either landing or taking off at a local airport but 1000's of Km are not possible, 20Km is the very most I could find in 40,000 records but the majority of Doppler shifted signals were at shorter distances. There are thousands of Aircraft in flight at any time and many thousands of WSPR signals present too yet the Doppler shifted spots in the record are confined to a handful  of spots, further evidence of the inability of WSPR to detect Aircraft at altitude.

OTHR is not simple or cheap. Many Nations have tried and failed , it is a very difficult processing problem. Many different systems, antennas and processes have been tried.  The recipe is simple, 1-40MW ERP,  100-500 element arrays for TX and separate RX array with as much computing power as you can get. You need to track the state of the ionosphere continuously ( the underside is not flat at all) and try to process out groundclutter which can be 80dB above the signal you are trying to track for just one hop.

If they could have done it with 5W TX power and dipoles they would have! But you would not choose a 2 min cycle to track a fast jet that has moved 30 miles, even an Airliner can move 20 miles in 2 mins.

Godfrey can only lift data from the WSPR database that is the only data available. The civilian flight plotting services all depend on ADSB which is a record of signals received from aircraft transponders ( secondary Radar) but the MH370 pilot turned off the transponder after the first waypoint so there is NO record of where MH370 went subsequently apart from the Inmarsat "Arcs", single arcs of position at roughly hour intervals.

As far as I  am aware Godfrey used the known position of a search aircraft to test his theory. He selected WSPR records that matched the known position of an aircraft. This is a false  many-one mapping, you are not finding an aircraft position but connecting noise to a point in space and time. This is similar to Ley Lines where people joined up  a few mapped antiquities with lines, this does not prove that churches, hill forts and settlements built over many thousands of years were deliberately built in lines but that the human brain has a very strong desire to make connections where there may be none. This feeds into our love of detective stories and concealed conspiracies with the opportunity to make millions out of inventing fantasy.

A problem with WSPR is that it is an indeterminate receiver, the SNR is the ratio of the averaged received signal to the local noise level in the RX bandwidth. So variable levels of QRM, QRN and other transmitters randomly keying up and down all modulate the SNR number in random ways. SNR is not an absolute number but a relative-to-the-noise ratio, those are the SNR numbers in the database, the SNR is subject to random variations that are not separable. A good example of the variation is the Noise plots produced by some KiwiSDR software which measures the noise levels between WSPR transmissions. These vary considerably over a day, vary every day and are different for every spotter.

If anyone has looked at the links in my last post they would have seen two independent evidential details that support the Christmas Island destination, the Cocos Island seismic event and the Flaperon Barnacles.   The Flaperon from MH370's wing had trailing edge damage consistent with a ditching but there were also Barnacles that could only grow while the flapperon was in Tropical waters not in the colder waters of Godfrey's suggested end point.

It seems obvious that Pilots fly to land safely. There have been a very few pilot suicides, they have chosen to fly into mountains or the sea at very high speeds. When this happens the aircraft shatters into very many parts many of which float, the debris field is vast and very easy to find. It is far more likely that the MH370 flight was towards an airfield  but that there was a ditching in the sea because the fuel ran out due to long periods of fuel draining low altitude flight.

Exhaust trails. They are condensation trails when the exhaust gasses meet the very cold air at altitude. They are similar to Clouds and are just as invisible to HF radio. Only visible at high microwave frequencies where water vapour resonances occur.

VHF reflections. This is a very well known observation especially if the antenna is positioned to null out direct signals to the illuminating transmitter or if the receiver is  deep down in a Valley.  Here the illumination is often very bright and the TX is close.  This was first set up by Arnold Wilkins near Daventry UK in February 1935. He used two dipoles and a goniometer to almost exactly null out a signal from a very powerful local HF broadcast station. When an aircraft flew nearby a fluctuating signal was received demonstrating the aircraft echo was detectable. The max range was around 12Km with many KW ERP. The experiment was a vital initial step towards the development of Radar in the UK.

However the MH370 affair concerns HF signals with very weak illumination at 1,000Km ++ ranges and a reflected much smaller signal that is said is detectable 1,000's of Km further away. Chalk and Cheese!

73, Alan G8LCO