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Antena that can sense thermal Radiation from human body

Discussion in 'Electronic Basics' started by Jiks, Mar 18, 2007.

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  1. Phil Allison

    Phil Allison Guest

    "Anthony Fremont = Psycho **** from Hell "

    The most asinine, ASD FUCKED pile of human puke on usenet.



    ** Nope .....

    Satan would be soo jealous of losing your undivided attention.

    Sucking his tiny, cold dick it your full time occupation.



    ** Shame about all the UTTERLY ASININE FUCKWIT assumptions

    brain dead, ASD fucked shitheads who post here make !!!!!!!!


    Oh - now I see my tiny oversight .... all those brain dead scumbags

    must be your six toed, pointy headed, dribbling, farting, puking relatives.

    Yet to come down from the trees.

    Still hanging their tails & eating their own shit.




    ....... Phil
     
  2. MassiveProng

    MassiveProng Guest

    Let alone the fact that anyone can calculate a frequency from a
    period, and the fact that your figure was far more accurate than his
    was, as was your description of what might be occurring.

    He is an idiot (PhilTard). I would ignore him completely.

    There was no plagiarism, even if you had read his CRAP first.

    I am sure we'll see a flurry of "ASD fucked ASS" posts as a result,
    however. He is famous for authoring meaningless, retarded, off topic
    trolls of other posters.
     
  3. Phil Allison

    Phil Allison Guest

    "Massive Prick Criminal Psychopath from Hades "


    ** Of course there is

    - you asinine pile of rabid dog's vomit.



    ** Got SFA to do with " plagiarism"


    - you fucking illiterate, donkey cock sucker.





    ....... Phil
     
  4. Phil Allison

    Phil Allison Guest

    "Massive Prick Criminal Psychopath from Hades "


    ** Of course there is .....

    - you asinine pile of rabid dog's vomit.


    ** Got SFA to do with " plagiarism"

    - you fucking illiterate, donkey cock sucker.




    ....... Phil
     
  5. MassiveProng

    MassiveProng Guest


    You're an idiot. No deliberation required to assess that one.

    The term for today is:

    Public Domain.

    Shame that australia's ISPs don't **** people like you out of Usenet
    as you so richly deserve.
     
  6. Phil Allison

    Phil Allison Guest

    "Massive Prick the Autism Victim from Hell "


    ** Got SFA to do with "plagiarism" within the same thread on NG.


    YOU FUCKING DUMB AS DOG SHIT ASSHOLE





    ...... Phil
     
  7. So now you're going to start a cross posted thread to rally support against
    me? As if! Charles Manson has more friends than you _and_ way more social
    appeal. You really are a pathetic case phil.

    Don't even think for a minute that you are going to trash SEB the way you
    trashed those Oz groups. If need be, I'll post a FAQ twice a day that tells
    newbies about you.

    I guess I wasn't clear enough before, so here it is again:

    "Hey phil this is serious, can I talk to you for a second? This is SEB,
    where there are no stupid questions. Only the occasional stupid fucking
    asshole like yourself. Go **** yourself and then drop dead you idiotic
    moron. You know philthy, it's reall too bad that you don't work with high
    voltages. Keep poking in those CFLs though, you may get just what you
    deserve. HTH HAND FOAD"

    Now shove that up your ass where you can get a good look at it.

    Now go and repeat yourself again. Or if you're really feeling frisky, go
    ahead and try to put a couple of words together without making a bigger ass
    of yourself. Good Luck!
     
  8. MassiveProng

    MassiveProng Guest

    Grow up, you retarded dumbfuck!
     
  9. Phil Allison

    Phil Allison Guest

    "Anthony Fremont = Psycho **** from Hell "

    The most asinine, ASD FUCKED pile of human SHIT on usenet.


    ** Nope .....

    Satan would be soo jealous of losing your undivided attention.

    Sucking his tiny, cold dick it your full time occupation.



    ** Shame about all the UTTERLY ASININE FUCKWIT assumptions

    brain dead, ASD fucked shitheads who post on SEB make !!!!!!!!


    Oh - now I see my tiny oversight .... all those brain dead scumbags

    must be your six toed, pointy headed, dribbling, farting, puking relatives.

    Yet to come down from the trees.

    Still hanging by their tails & eating their own shit.





    ....... Phil
     
  10. Gareth

    Gareth Guest

    The power received by an antenna due to thermal radiation is KTB, where
    K is Boltzmann's constant, T is the antenna noise temperature in K and B
    is bandwidth in Hz. Since Boltzmann's constant is very small
    (1.3806503E-23) the power due to thermal noise is received by the
    antenna is very small.

    The antenna noise temperature is the average of the noise temperature of
    everything the antenna 'sees' weighted by the antenna gain in that
    direction.

    Therefore you want a highly directional antenna so that the antenna
    beamwidth is completely filled by the person. You also want a wide
    bandwidth so as to maximise the power received. A dish antenna is
    therefore probably a good choice.

    The temperature of people is about 300K. Assuming an antenna bandwidth
    of 1 GHz you should get about:

    1.38E-23 * 300* 1e9 = 4.14e-12 W = -83.8 dBm

    You will not be able to see that on an oscilloscope. To get it up to a
    detectable level you want a low noise, high gain amplifier after the
    antenna, then feed the output of the amplifier to a power detector and
    smooth the output of the power detector with a low pass filter. Now
    point your antenna at something with a very low noise temperature (the
    sky is good for this, about 10k) and record the output voltage after the
    low pass filter. Now point your antenna at a person - you should see a
    small change in output voltage.

    Another problem you have trying to detect thermal radiation from people
    is that the background also emits thermal radiation, often at a very
    similar level.

    I don't know what that signal you saw on your CRO was, but it doesn't
    sound like thermal radiation. It could be some sort of interference
    which is being picked up more efficiently by the antenna.

    --
     
  11. Gareth

    Gareth Guest

    The same way an IR sensor does it. Infra Red and radio waves are both
    electromagnetic radiation. As you rightly said, all objects above
    absolute zero emit IR but they also emit radio waves and, if they are
    hot enough, visible light.

    It is a lot easier to use IR sensors, but if you have a sensitive enough
    system you can do it at microwave and RF frequencies as well.

    --
     
  12. Phil Allison

    Phil Allison Guest

    "Gareth the Pommy Jerk Off" "


    ( snip pile of excremental drivel )


    ** What drugs are you on - imbecile ?

    A massive overdose of Google Drops ??

    All swallowed whole without a tiny drop of comprehension.


    Who do you think you are kidding - fuckwit ?




    ........ Phil
     
  13. Phil Allison

    Phil Allison Guest

    "Gareth the Pommy Jerk Off" "


    ( snip pile of excremental drivel )


    ** What drugs are you on - imbecile ?

    A massive overdose of Google Drops ??

    All swallowed whole without a tiny drop of comprehension.

    Who do you think you are kidding ?

    Lemme tell ya - it is nobody.




    ........ Phil
     
  14. Gareth

    Gareth Guest

    Phil,

    If you want to killfile or ignore everyone who posts here, why don't you
    just stop reading this group? That way you would never have to read any
    of my, as you put it in your earlier reply, "pile of excremental drivel"
    ever again?
     
  15. MassiveProng

    MassiveProng Guest


    I DOUBT VERY SERIOUSLUY that in our world's RF RICH environment, that
    you or anyone else will be sensing body temperature related events
    from an RF antenna anytime soon. The "signal" if any is so far below
    the baseline noise that you will not be able to pick it out, if it
    exists at all.

    That is what IR detectors (resistor bolometers) and IR Imagers (CCDs
    and CMOS arrays) are for. And even those need cooling to reduce noise
    for high sensitivity applications. Many also need spectral filtering.

    DOH!
     
  16. Fred Bloggs

    Fred Bloggs Guest

    LOL!!!!!!! Very funny stuff!!!!!!!
     
  17. Gareth

    Gareth Guest

    It has been done, by me and lots of other people

    http://www.qinetiq1.com/home/security/national_security/securing_national_borders.html

    http://www.roke.co.uk/download/casestudy/040-pandora.pdf

    http://www.tadarvision.com/
     
  18. J.A. Legris

    J.A. Legris Guest

  19. MassiveProng

    MassiveProng Guest


    But what you sense are local RF reflections and amplifications, not
    the temperature or any emission from the nearby test mass.

    Same reason why an AM radio tunes differently while in your hand
    than after setting it down. That is why an AM radio tuned via remote
    locks onto the station better than hand tuning, and then walking away.
     
  20. Gareth

    Gareth Guest

    The links I posted refer to systems which detect the thermal noise
    emitted by the object itself. Measurements of thermal radiation emitted
    at microwave and mm wave, as well as IR, are well established techniques
    for remote sensing from satellites. The techniques have more recently
    been applied to the detection of people for security applications.
    I'm aware of that effect, but the actual thermal radiation emitted by a
    person can also be detected at microwave frequencies with suitable
    equipment.

    --
     
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