Millimeter Waves and Junk Pictures

With all the attention given to the TSA and the Full-Body airport scanners, I thought it would be interesting to explain some of the technology involved. Currently there are 2 types of full body scanners being used, Millimeter Wave and X-Ray BackScatter.

Let’s begin with the Millimeter Wave scanner, MMW.

So, why do they call it “Millimeter Wave” radar?

The millimeter refers to the wavelength of the energy that is used. Wavelength?? Huh?

To explain wavelength, just think of a jump rope with one end tied to a wall and the other held by a person.

If that person gives the rope a continuous quick up and down motion, you can see the wave go on the rope from the persons hand to the wall.

The distance from one peak of a wave to the next is called the wavelength

So the more “wavelengths” or cycles in a given amount of time, the quicker those wavelengths will pass a given point. This rate or “cycles per second” is called “frequency” and it can be thought of as the quantity of items that pass a point.

Frequency used to be measured in units called obviously…cycles per second. But to honor a scientist, Heinrich Hertz, a few years back they changed the “cycles per second” to the unit “hertz”. Means the same thing.

Now electromagnetic radiation travels in a vacuum at a really, really, fast speed. Precisely measured at 299,792,458 meters per second.

Now suppose someone stated that they have a transmitter that sends out energy at a frequency of 299,792,458 hertz. What do you think the distance traveled in one wavelength would be?

Think about it, you have 299,792,458 cycles and it travels at 299,792,458 meters in one second. So 1 wavelength would be 1 meter.

Notice how the wavelengths get smaller and smaller as the frequencies go up.

Am radio station may have a full wavelength of 240 meters. Since antennas are usually made to be 1/4 of the wavelength, that may mean it needs an antenna of 60 meters. A 1/4 wavelength CB antenna may be about 2.7 meters long.

So in an indirect way, wavelength can be used as a different way of stating the frequency of the energy transmitted.

Here is a picture that shows you the relative wavelengths of several frequencies.

Interesting note is that visible light is just electromagnetic radiation at a narrow wavelength or frequency.

A cheap laser pointer may state a wavelength of 650 nm. This means a wavelength of 650 nanometers or the frequency of an astonishing 450 Terahertz. But our eyes just happen to be able to see that energy so it would be the color red. A simple red laser pointer.

But you can see how the frequency number is getting impossibly large. That’s one reason that it’s easier to say it in wavelength.

Okay, getting back to the TSA body scanners. They are called millimeter wave radar because that’s the range that they operate in. About 5 millimeters so they use a energy of around 60 gigahertz although some scanners work at a lower frequency of around 30 gigahertz.

That is really high up in radio frequency, way beyond cell phones and your free Starbucks WiFi connections.

In fact, until recently it was impossible to have electronic components that could produce radio frequencies that high.

Millimeter Wave radar was only developed in the early 1960’s for the military by Georgia Tech and it was not what you would call portable and cheap.

There are several interesting qualities about frequencies when they get this high…. besides the obvious one of it being impossible to design compact without complete computer simulation.

The transmitted energy is absorbed by oxygen quite rapidly so they cannot transmit very far in air. It’s very narrow and directional and can be designed so that it reflects off organic material with moisture content such as skin, but goes right through materials such as cloth.

When a passenger steps into a scanner booth, a scanning array of transmitter/ antennas sweep across your body from about 2 feet. The received beam that has gone through your clothes and bounced back must be digitally processed before it can even begin to resemble a picture.

But because of the direct reflection and short wavelength, the picture it produces is quite detailed.

The person literally is being viewed naked by a TSA agent. The picture below has the face blurred out and some detail smudged, but make no mistake about it….the process produces a VERY detailed nude picture.

In my opinion, this is where the Millimeter wave scanners have failed and the public relations has been a disaster. There’s no need to have that much nudity detail displayed.

It’s almost like some geeky engineer said…”Look at what I can do”.

Because of the extensive digital processing, you could have just a stick figure being displayed. In fact, Germany has this method in operation already. The digital processing can discern far more detail and patterns to look out for than a slightly higher than minimum wage paid TSA agent.

Hell, even the new XBox Connect on sell for Christmas this year can do facial and pattern recognition beyond what a TSA agent could do. The TSA doesn’t even need to have a body displayed. Let the machine do the scan and make the decision that the person needs to be checked further. Simple red light / green light.

In my opinion, that would be the ideal system that would alleviate a lot of peoples concerns about privacy. Maybe that will be a couple of revisions down the road for the company that makes these scanners.

My hope is that the changes come around quickly because they are just too intrusive right now.

As far as genetic risks from millimeter wave scanners, studies have been done but so far there is no conclusive evidence that millimeter wave scanners cause any DNA or genetic harm.

If any reader can point out a scientific peer reviewed study that does indicate genetic damage, please post a link to the study in comments and this post will be revised with that new information.

Millimeter Wave Full-Body Scanner

The next post will go into the other system, X-RAY BackScatter. This is the system that people are concerned about with the ionizing radiation. Should it be a real concern?

Next post…..X-RAY Back Scatter and Junk Pictures.

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Posted by on December 2, 2010. Filed under Commentary. You can follow any responses to this entry through the RSS 2.0. You can leave a response or trackback to this entry
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19 Responses to Millimeter Waves and Junk Pictures

  1. Holte Ender Reply

    December 2, 2010 at 12:37 pm

    Very interesting, even though most of the technology is beyond me.

    I don’t fly often to have a concern about being harmed, but in recent weeks I have read conflicting articles, one saying you have to be scanned 30 times to get equivalent radiation you get from an X-ray and another saying a 1,000 times? There is a lot of mis-information out there and you are right, it has been a public relations disaster.

    • Krell Reply

      December 2, 2010 at 12:44 pm

      Holte, for some reason that initial trials of body scanners were set up for 2 different technologies by Homeland security and they were supposed to battle it out for the best method. I suspect that there may have been a tinge of politics involved as well.

      When people talk about X-Rays…they really are meaning the system called the X-Ray Back Scatter scanner which is the subject for my next post of this series.

      Both systems have been grouped together in the general populations eye but they are different.

      • Jess Reply

        December 2, 2010 at 1:23 pm

        How do you think people that have implanted devices would fair through these machines?

        • Krell Reply

          December 2, 2010 at 1:48 pm

          Very good point, Jess. A pacemaker does have electronic components and is probably not very well shielded. It’s quite common to see warning signs in restaurants about microwaves in use and pacemakers. And this would have lots more energy than a RF leaky microwave oven.

          If I had a pacemaker, (or some people would say..even a heart), I would absolutely cancel the flight before I walked through a MMW body scanner.

          Perhaps Dick Cheney can test it out on his way to Nigeria? We can only hope.

          • Jess Reply

            December 2, 2010 at 5:06 pm

            Ok well I called TSA and asked them what about people that have implants. You know like those stimulator thingys for nerve pain. I’m trying to get one tested on me, and I fly frequently so I wanted to know. Anyway I digress, TSA said that if you had an implant like that, you can forego the machine, even the metal detector, because the doo dad will set that off. You have to show that you have the device, guess there is some kind of ID for it, like there is a pacemaker, probably serialized. The agents will then do the grope and tug. So I guess that answers the question for us.

            • Krell Reply

              December 2, 2010 at 5:20 pm

              When it gets to be time for the grope, tug and twist…that is when you place your Johnny Depp request.

              They HAVE to honor it.

              • Jess Reply

                December 2, 2010 at 5:24 pm

                Hmm, last time I checked I have nothing to tug, but the groping and twisting oh yeah JD can go to it. He is one of my, get out of hubby being mad free cards.

    • Krell Reply

      December 2, 2010 at 12:50 pm

      Something else that is interesting about this technology of millimeter wave scanners and radar. If you go a little bit higher in frequency and shorter wavelength. Around the 100 GigaHertz and 2.7 millimeter range, the energy starts to change from completely reflecting and starts to absorb in the skin…but only abut a 1/2 wavelength or about 50 thousandths of an inch.

      This is the technology behind the Active Crowd Dispersal Weapon used by US and the Israelis.

      http://en.wikipedia.org/wiki/Active_Denial_System

  2. vivzizi Reply

    December 2, 2010 at 3:28 pm

    “If any reader can point out a scientific peer reviewed study that does indicate genetic damage, please post a link to the study in comments and this post will be revised with that new information.”

    This is exactly the INCORRECT way to handle risk to humans of new technology – especially forced technology incorporating things similar to things we know DO cause harm.

    New technologies must be proven SAFE not the other way around.
    For example there is no peer reviewed study that shows that exposing yourself quickly and repeatedly to ultra short bursts of heat at 4000 degrees will cook you. There are plenty though that show longer bursts will cook you as does common sense. Should you be forced to stand in a short burst cooker just to fly a plane just because no studies have shown short burst exposure to the same energy cooks you?

    The same is true with any radiaton and so is the common sense.

    Peered review studies take YEARS – first to get funding and approval for the study, then for the study, then the peer review process then the publication. Should everyone be exposed until those are completed?
    Further recent review f “peered reviewed” medical journal have found so much influence of medical pharmaceutical money that “up to

    Based on recent studies peer reviewed journals are on average by any empirical measurement MORE corrupted from fact and influence BECAUSE of its high regard in society. Organizations corrupt the article precisely because people like you believe “peer review ” to be above influence.

    Look it up yourself let me google that for you.
    http://www.google.com/search?hl=en&safe=off&biw=1280&bih=793&&sa=X&ei=FP33TN2YIpDSsAOKwf2iAg&ved=0CBIQBSgA&q=corporate+influence+on+peered+reviewed+medical+articles&spell=1

    http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1000335
    or in laymans terms
    http://www.naturalnews.com/012119.html

    But even in “peered reviewed journals”

    There are loads of studies that have shown higher frequency radio wave energy causes genetic damage. Many have come out of Europe regarding cell phone frequencies. Should we require that every single frequency be individually proven harmful? Isn’t it enough to know that frequencies cause harm and therefore it is reasonable to assume UNLESS PROVEN SAFE that other frequencies at high intensities like occur in the skin level with TSA scanners cause harm?

    Use common sense and logical scientific reasoning. If high frequency skin penetrating radio waves like cell phone radiation cause harm then varying the frequency will likely also cause some harm in unknown ways.

    And furthermore limiting it to “genetic damage” is a false exclusion. We have no idea the effect of these higher frequencies on the atomic level and we have little understanding of the effect of atomic level changes in the body. what if these frequencies altered the isotope ratios of hydrogen in the body? What if they caused sideband frequencies which interfered with intercelluar communication in the brain of other matrices in the body. We simply have NO IDEA what KIND of harm penetrating frequencies do but we KNOW that energy is going somewhere and is thus changing SOMETHING in the substrate of the skin down to half a millimeter.

    What is scientifically logical and usually pans out is if you expose a human body to any environment,energy or substance which it did not evolve in and thus adapt to then that environment,energy or substance is likely to cause changes in the body and the high probability is those changes will NOT be positive since the whole body is balance base don it’s previously evolved condition.

    Thus it is scientifically valid to EXCLUDE human exposure to non evolved energies and higher concentrations of those energies unless they are PROVEN SAFE.

    but you wanted some research and let me google that for you.

    http://scholar.google.com/scholar?hl=en&q=cell+phone+radiation+genetic+damage+&btnG=Search&as_sdt=2000&as_ylo=&as_vis=0

    Choose from the hundreds of articles or read some of the choice other quotes I found and noted below my signature including how little radiation the Russian bombarded the American embassy with by comparison which caused numerous health problems in Embassy employees.

    This un proofed article took me an hour to write just to do the work and exercise the scientific common sense you didn’t do. Unfortunately I can’t spend more time on it but then again unlike you I am not being paid to do it. Next time do the damn research before writing unless of course you too are influenced by the manufacturers money and advertising which is highly likely. In that case please keep posting their apologetic “no proof” common sense denying, tripe arguments as you are being paid to do.

    vivzizi

    http://books.google.com/books?id=2azJ1LSncfAC&pg=PA150&lpg=PA150&dq=cellphine+radiation+causies+genetic+damage&source=bl&ots=HZHLMzy3jy&sig=rriq9QrqgXdINBz5TTMD0ziEaVs&hl=en&ei=rfr3TO3aK4a0sAOn-uXDAg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBIQ6AEwADgK#v=onepage&q&f=false

    or
    http://genetichemistry.com/genetic-memory/do-cell-phones-really-cause-cancer/

    “During the Cold War, the Soviets bombarded U.S. embassy workers with an average exposure of only .01 microwatt per square centimeter.

    The illnesses at the embassy made international news. There has been no funding to look at the cumulative effects of the myriad of EMF types of exposure. But there are reports of an instantaneous spike in mortality after cell phone service began in the 1990s.

    In some cities, the rate of mortality went up by 10-25% compared to the typical death rate. Let’s look at studies abroad: A French 2002 study found living close to a cell phone tower can cause extreme sleep disturbance, chronic fatigue, skin problems, brain disturbances, and cardiovascular problems.

    A German study found a high rate of cancer developing on average eight years earlier than national averages if you live within 1,200 feet of a cell tower. Spanish researchers found significant illness increases at a radiation exposure of only 0.11 to 0.19 microwatts.”

    • Krell Reply

      December 15, 2010 at 12:59 pm

      “If any reader can point out a scientific peer reviewed study that does indicate genetic damage, please post a link to the study in comments and this post will be revised with that new information.”

      This is exactly the INCORRECT way to handle risk to humans of new technology – especially forced technology incorporating things similar to things we know DO cause harm.

      New technologies must be proven SAFE not the other way around.
      …….
      I agree with that statement to a point. The reality is that science applied to products is a continuing review process. You test to a reasonable safety level, get feedback, continue testing after product release. There have been some products that were thought to be safe but were later pulled by recall.
      …….
      For example there is no peer reviewed study that shows that exposing yourself quickly and repeatedly to ultra short bursts of heat at 4000 degrees will cook you. There are plenty though that show longer bursts will cook you as does common sense. Should you be forced to stand in a short burst cooker just to fly a plane just because no studies have shown short burst exposure to the same energy cooks you?
      …….
      I don’t even understand this argument
      …….
      The same is true with any radiaton and so is the common sense.

      Peered review studies take YEARS – first to get funding and approval for the study, then for the study, then the peer review process then the publication. Should everyone be exposed until those are completed?
      Further recent review f “peered reviewed” medical journal have found so much influence of medical pharmaceutical money that “up to

      ……
      I do not argue that there is considerable “influence” in the
      drug development and approval process.
      ……
      Based on recent studies peer reviewed journals are on average by any empirical measurement MORE corrupted from fact and influence BECAUSE of its high regard in society. Organizations corrupt the article precisely because people like you believe “peer review ” to be above influence.

      Look it up yourself let me google that for you.
      http://www.google.com/search?hl=en&safe=off&biw=1280&bih=793&&sa=X&ei=FP33TN2YIpDSsAOKwf2iAg&ved=0CBIQBSgA&q=corporate+influence+on+peered+reviewed+medical+articles&spell=1

      http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1000335
      or in laymans terms
      http://www.naturalnews.com/012119.html

      But even in “peered reviewed journals”

      There are loads of studies that have shown higher frequency radio wave energy causes genetic damage. Many have come out of Europe regarding cell phone frequencies. Should we require that every single frequency be individually proven harmful?
      ……
      Again, I stand by my statement that it is power density that causes damage. Cell phones produce a larger concentration of RF power on a smaller surface than the MMW scanner. Note that I am talking only the MMW scanner. Read later post on X-Ray scanner.
      ……

      Isn’t it enough to know that frequencies cause harm and therefore it is reasonable to assume UNLESS PROVEN SAFE that other frequencies at high intensities like occur in the skin level with TSA scanners cause harm?

      Use common sense and logical scientific reasoning. If high frequency skin penetrating radio waves like cell phone radiation cause harm then varying the frequency will likely also cause some harm in unknown ways.

      And furthermore limiting it to “genetic damage” is a false exclusion. We have no idea the effect of these higher frequencies on the atomic level and we have little understanding of the effect of atomic level changes in the body. what if these frequencies altered the isotope ratios of hydrogen in the body? What if they caused sideband frequencies which interfered with intercelluar communication in the brain of other matrices in the body.
      ……
      Again, this post was about the MMW scanners. Ionizing radiation energy such as that used by the X-Ray scanner is discussed in a later post
      ……
      We simply have NO IDEA what KIND of harm penetrating frequencies do but we KNOW that energy is going somewhere and is thus changing SOMETHING in the substrate of the skin down to half a millimeter.

      What is scientifically logical and usually pans out is if you expose a human body to any environment,energy or substance which it did not evolve in and thus adapt to then that environment,energy or substance is likely to cause changes in the body and the high probability is those changes will NOT be positive since the whole body is balance base don it’s previously evolved condition.

      Thus it is scientifically valid to EXCLUDE human exposure to non evolved energies and higher concentrations of those energies unless they are PROVEN SAFE.

      but you wanted some research and let me google that for you.

      http://scholar.google.com/scholar?hl=en&q=cell+phone+radiation+genetic+damage+&btnG=Search&as_sdt=2000&as_ylo=&as_vis=0

      Choose from the hundreds of articles or read some of the choice other quotes I found and noted below my signature including how little radiation the Russian bombarded the American embassy with by comparison which caused numerous health problems in Embassy employees.

      …..
      The reason that the Russians bombarded the embassy was due to passive resonant cavity listening devices embedded in the building for spying purposes. Not to cause some secret DNA mutation war.
      …..

      This un proofed article took me an hour to write just to do the work and exercise the scientific common sense you didn’t do. Unfortunately I can’t spend more time on it but then again unlike you I am not being paid to do it.
      ……
      My posts take longer than a hour to write, I have over 25 years of engineering experience designing embedded measurement equipment that uses rf energy,ultrasound in the Mhz range,etc.

      I don’t get paid for writing these posts. Just do it for the pleasure of writing and getting read.
      …….

      Next time do the damn research before writing unless of course you too are influenced by the manufacturers money and advertising which is highly likely.
      …….
      I am not going to respond to that first sentence. As for influenced by manufacturers money or advertising, I have to say that there is almost no advertising on this site and the audience that the Scanner Manufacturers would pay money to influence would be a lot larger than this audience. Think articles and opinions in major mags and newspapers. Much larger market base.
      …….
      In that case please keep posting their apologetic “no proof” common sense denying, tripe arguments as you are being paid to do.
      …….
      Are you trying to say “common sense denying,no proof tripe arguments? Sounds better that way don’t you think?

      …….

      vivzizi

      http://books.google.com/books?id=2azJ1LSncfAC&pg=PA150&lpg=PA150&dq=cellphine+radiation+causies+genetic+damage&source=bl&ots=HZHLMzy3jy&sig=rriq9QrqgXdINBz5TTMD0ziEaVs&hl=en&ei=rfr3TO3aK4a0sAOn-uXDAg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBIQ6AEwADgK#v=onepage&q&f=false

      or
      http://genetichemistry.com/genetic-memory/do-cell-phones-really-cause-cancer/

      “During the Cold War, the Soviets bombarded U.S. embassy workers with an average exposure of only .01 microwatt per square centimeter.

      The illnesses at the embassy made international news. There has been no funding to look at the cumulative effects of the myriad of EMF types of exposure. But there are reports of an instantaneous spike in mortality after cell phone service began in the 1990s.

      In some cities, the rate of mortality went up by 10-25% compared to the typical death rate. Let’s look at studies abroad: A French 2002 study found living close to a cell phone tower can cause extreme sleep disturbance, chronic fatigue, skin problems, brain disturbances, and cardiovascular problems.

      A German study found a high rate of cancer developing on average eight years earlier than national averages if you live within 1,200 feet of a cell tower. Spanish researchers found significant illness increases at a radiation exposure of only 0.11 to 0.19 microwatts.”

  3. vivzizi Reply

    December 2, 2010 at 4:07 pm

    Again, apparently lazy researcher, let me google that for you

    This time for ghz radiation

    http://scholar.google.com/scholar?hl=en&q=ghz+radiation+genetic+damage+&btnG=Search&as_sdt=2000&as_ylo=&as_vis=0

    Hmmm over 100 studies pop up immediately . Even if only 1 tenth found evidence of a problem that’s a lot of problems! And as even a cursory perusal shows a lot more than that find evidence for damage.

    And the radiation does not “bounce off skin” as you say. It does penetrate to a thin level and the fact that it penetrates to a thin level is exactly why the dosage is so concentrated in those top layers of skin cells and why it is a problem.

    Furthermore remember the act of “bouncing” itself causes energy transfer to the skin atoms and molecules and cells the energy “bounces” off of. If you don’t believe me go let someone “bounce” something off your head.

    Then tellme how you fele baout that GHZ energy “bouncing” off your moleclules.

    Remember molecules in cells are vibrating at over one million times a a sec. That’s how molecular chemistry works. If you are bombarding molecules that are vibrating at millions of times a second with energies at ghz frequencies you are produced additive, subtractive and sideband frequencies to those molecular reactions that no one will likely ever know how they influence the probabilities of those reactions taking place in the normal reaction ratios.

    vivzizi

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  5. A Michael J. Scott Reply

    December 2, 2010 at 5:00 pm

    This is great stuff Krell. Although I didn’t understand all of it I did understand enough to assure me that these scans do not appear to be harmful. Thanks and I will be looking forward to your next iteration.

  6. Krell Reply

    December 2, 2010 at 5:01 pm

    Well, I have been accused of lazy but normally that’s when it’s time to load the dishwasher.

    I did research on this post and I stand by what is says. The thing to remember is that ANYTHING can cause damage if it’s in great enough quantity and time. The first item on your link is a study that indicates cell damage with an exposure of a power density (10, 20 and 30 mW/cm2) for three times (15, 30 and 60 min).

    The study then indicates that damage can cause cytogenetic damage in human lymphocytes mainly for both high power density and long exposure time as indicated above.

    The millimeter body scanner does not produce anything near that kind of power exposure and for those durations.

    It is all about the power density. A 40 watt bulb shining on you causes no harm but a 1 billion candlepower spotlight might set you on fire. But it’s the same type of spectrum radiation. IT’S ALL ABOUT THE POWER DENSITY!

    Again, if you can show me a peer reviewed scientific study that shows genetic damage with the power levels and duration of the millimeter wave scanners currently in use, put the link up.

    Also you may have more credibility if you knew your physics and unit nomenclature. Giga does not equal 1 million, light can bounce off my head every day without damage, there isn’t such a phenomenon as subtractive frequencies, human cells cannot act as a mixer to produce sideband frequencies. Oh and spell check is free and easy to use.

    • Krell Reply

      December 2, 2010 at 5:15 pm

      Probably the one study that I would like to see more research into is this one…A possibility of Bubble effects in DNA Strands of Terahertz Rf Fields.

      http://arxiv.org/PS_cache/arxiv/pdf/0910/0910.5294v1.pdf

      But they conclude that

      “Hence, the occurrence of a fluctuation with sufficiently large amplitude is very rare, and therefore extended exposure is required.”

      They put forth the idea that DNA strands may be effected by a harmonic resonance of particular frequency and power. Almost like a certain frequency will cause a bell to start ringing from across the room.

      • Krell Reply

        December 2, 2010 at 5:36 pm

        Additional note, the current ProVision100 Millimeter Wave Full-Body scanner has been measured at .00000597 mW/cm2 power density.

        The average cell phone has a radiated power density of 37.5 mW/cm2.

        Listen, I am not meaning for my post to be an endorsement for millimeter wave scanners. In fact, I have a lot of problems with them. But the technical facts are just that…

        The problems I have concerns privacy and the present state of what is being displayed with the machine.

        I DO have some technical issues with the X-RAY backscatter machines, but that is going to be on the next post.

  7. mbarnato Reply

    December 2, 2010 at 6:21 pm

    FYI in case you haven’t read it: a letter of concern from UCSF faculty to John Holdren:
    http://www.npr.org/assets/news/2010/05/17/concern.pdf

    • Krell Reply

      December 2, 2010 at 6:29 pm

      Again, the X-RAY BackScatter scanners are going to be on the next post.

      I DO have concerns about that type of scanner.

      This post was about the Millimeter Wave Scanners. They are 2 separate types.

      The comment above just illustrates again the PR DISASTER that the TSA and Airport have created. In the public’s mind, all are the same. To me that is unfortunate.

  8. osori Reply

    December 2, 2010 at 8:00 pm

    Krell,great and informative post.Brings to mind some of the stuff I learned in transmission school as we were going digital.

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