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Relationship between antenna gain and range

  1. Nov 22, 2011 #1
    Im trying to expand the range of my wifi network, and Im not sure exactly what to expect from a +27 dbi antenna. As I understand it, this will cause the power density to increase by a factor of 2^9. Does that mean the range will increase by a factor of 2^9? or would it be more like sqrt(2^9) from an inverse square law? or something else entirely? If anyone knows the math behind this stuff, Id really appreciate any help. Thanks.
    Last edited: Nov 22, 2011
  2. jcsd
  3. Nov 23, 2011 #2
    ok, let me preface this by warning you all: I havent taken a math or physics class in over a decade. So I apologize in advance for any logical or notational inconsistancies.

    w = power density
    G = initial gain
    G' = final gain
    P = power
    r = initial distance from antenna
    r' = final distance
    k = proportionality constant

    from this equation:
    w=G*P*k / 4*pi*r^2

    so if P, k, and W are constant...

    G*p*k / 4*pi*r^2 = G'*p*k/4*pi*r'^2


    G'/ G = r'^2 / r^2


    r * sqrt(G'/ G) = r'

    so, as I understand it, after a gain increase of +27 dbi, and a distance increase by a factor of sqrt(2^9), there will be the same power density. Does this math make sense? Does this mean that the range of my wifi network will also increase by sqrt(2^9)?
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