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    power harvesting using radio frequency energy

    circuit for the project. can any one help with the best parameter values to use for this circuit?

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    Re: power harvesting using radio frequency energy

    Whoever designed that is an idiot.
    In the first place, to expect 0.58V from the antenna is unrealistic unless you place it directly underneath a high power transmitter antenna, normal ambient RF radiation only produces microvolts of output. Then to put it through many stages of voltage multiplication, each losing about 0.5V means nothing would reach the output anyway. I guess it was designed by someone who imagines the RF power levels around us are massively greater than they actually are and that the power comes from nowhere in the first place. If you want it to work, place it directly underneath your local radio stations antenna. Of course you could just plug into their electricity supply and extract thousands if not millions of times more power for none of the cost!

    Brian.


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    Re: power harvesting using radio frequency energy

    Whoever designed that is an idiot.
    Without anything said about the intended operation conditions, one may get the impression.

    What's the intended operation frequency (I guess, 900 MHz GSM band)?
    Available field strength at the antenna? Output load?

    The circuit may work in the proximity (e.g. 10 cm) of an active mobile phone or the near vincinity of a base station.


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    Re: power harvesting using radio frequency energy

    I was reading an article about this in (what I'm ashamed to say is now a crackpot "science" mag) New Scientist a couple of months ago. It may be worth hunting that down to get an idea of what is being done elsewhere.

    Commercial state of the art systems for "rf harvesting" (like that term) are getting to be really good.

    Of course the maximum distances are very small and the returns diminishing
    but useful work is pretty close to being of some commercial interest for a couple of the systems described. (Assuming the editor can be trusted - the mag is now high on rhetoric and low on science)

    I think good old Tesla had the best idea myself though. Just charge the entire
    planet up.

    jack



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    Re: power harvesting using radio frequency energy

    I found the magazine and have attached an informative jpg about
    what is currently being achieved (claimed) commercially.
    Companies such as Intel and Sony are working on this.

    The article is in The New Scientist issue 6 February 2010.

    I hope I can get the jpeg attached ok I've not done that here before...



    jack



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    Re: power harvesting using radio frequency energy

    I must admit, the scenario looks nightmarish. Fortunately, I remember a number of safety regulations (laser and RF) that strictly prohibit the implementation of the technique if persons are near to the room.



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