Free-space Path Loss - Free-space Path Loss Formula

Free-space Path Loss Formula

Free-space path loss is proportional to the square of the distance between the transmitter and receiver, and also proportional to the square of the frequency of the radio signal.

The equation for FSPL is

\begin{align} \mbox{FSPL} &= \left ( \frac{4\pi d}{\lambda} \right )^2 \\ &= \left ( \frac{4\pi d f}{c} \right )^2 \end{align}

where:

  • is the signal wavelength (in metres),
  • is the signal frequency (in hertz),
  • is the distance from the transmitter (in metres),
  • is the speed of light in a vacuum, 2.99792458 × 108 metres per second.

This equation is only accurate in the far field where spherical spreading can be assumed; it does not hold close to the transmitter.

Read more about this topic:  Free-space Path Loss

Famous quotes containing the words path, loss and/or formula:

    “She’s in the house.
    She’s at turn after turn.
    She’s behind me.
    She’s in front of me.
    She’s in my bed.
    She’s on path after path,
    and I’m weak from want of her.
    O heart,
    there is no reality for me
    other than she she
    she she she she
    in the whole of the reeling world.
    And philosophers talk about Oneness.”
    —Amaru (c. seventh century A.D.)

    “Our loss put six feet under ground
    Is measured by the magnolia’s root;
    Our gain’s the intellectual sound
    Of death’s feet round a weedy tomb.”
    —Allen Tate (1899–1979)

    “The formula for achieving a successful relationship is simple: you should treat all disasters as if they were trivialities but never treat a triviality as if it were a disaster.”
    —Quentin Crisp (b. 1908)