Recent content by unseensoul

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    Fresnel Zone: Ellipsoids, Energy & Wavelengths

    Ok, I finally got it. This link http://www.zytrax.com/tech/wireless/fresnel.htm provides a very good explanation of it for those interested.
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    Fresnel Zone: Ellipsoids, Energy & Wavelengths

    I know fresnel zone is related to ellipsoids but what are these about? I was told they represent most of the energy transmitted by an antenna to another antenna. However, this makes no sense to me. Apparently, the width of the ellipsoid increases if the wavelength does so as well which makes it...
  3. U

    One sided noise spectral density VS double sided noise spectral density

    No is the one sided noise spectral density in communication systems. N is the double sided noise spectral density. The relationship between them is given by 2N = No but I don't understand why it is like that. Why isn't it N = 2No instead?!
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    Queries on Maxwell's Equations

    "The fact that the speed of light is constant regardless of your reference frame is a direct consequence of Maxwell's Equations". What direct consequence?
  5. U

    Queries on Maxwell's Equations

    I didn't get this last part and how it explains the unification of electricity and magnetism. Can you give me real life applications (for instance, in electronics) where they apply? Also, what sort of things can be derived from the equations?
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    Queries on Maxwell's Equations

    How can you figure that out from the equations? It's not obvious for me...
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    Queries on Maxwell's Equations

    "Maxwell's equations explain all electromagnetic phenomena." ...What does this mean exactly? How do these equations represent the unification of electricity and magnetism? What's really an unification? And how can you see it from the equations? Aren't his equations only applicable to EM waves?
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    Why Does Current Flow When a Capacitor Is Connected by Wires?

    There are no electric fields outside of a charged capacitor as they are canceled out due to superposition, right?! So why is there a flow of current when a cable is connected to both ends of the capacitor? I was told that there might be an E field in the wires. How come? Where does it come from?
  9. U

    Transfer function's poles and Auxiliary Equation

    Why does the homogeneous of a second order differential equation/system (i.e. a series RLC circuit) is identical to the transfer function (i.e. H(jw)) denominator in its standard form? Therefore the poles of the transfer function are also the solutions for the auxiliary equation... I cannot...
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    Special case when solving D.E.'s

    Where did you get this from?
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    Special case when solving D.E.'s

    D would vanish... That's why they have to be linearly independent? I can't think of it in practical situations.
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    Special case when solving D.E.'s

    Why can't there be common terms on both complementary function and particular integral when solving differential equations? For instance, dy/dx + 3y = exp(-x) + exp(-3x) y(CF) = Aexp(−3x) y(PI) = Cexp(−x) + Dxexp(−3x) The term Dexp(-3x) in the P.I. has to be multiplied by x to...
  13. U

    Forward Biasing a Diode: Explained

    Ok, I'll make the question in this way... Would there be conduction if I joined a n-type material (extrinsic) with an intrinsic silicon material and connected an external voltage across both ends (neglecting e-h pair generation)?
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    Forward Biasing a Diode: Explained

    There are a lot of resources out there which mention that when a diode is forward biased the majority carriers at the n-type material will move to the p-type material "through" the holes therefore the holes will move from the p-type region to the n-type region. However, this doesn't make any...
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    Deriving Capacitor Reactance: AC Signals & Ohm's Law

    Fair enough, but could you tell me why do we get a capacitor's reactance working out the ratio between the Vp and Ip? Why the peak values if they are 90 degrees out of phase? If you apply Ohm's Law directly to instantaneous values and work out their ratio it will fail. Where does such ratio come...
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