Polarization Mismatch Loss Calculator

For two linear antennas, the polarization loss factor is cos²θ, where θ is the angle between their axes, so the mismatch loss is −10 log₁₀(cos²θ) dB and a signal in the orthogonal plane is rejected by −10 log₁₀(sin²θ) dB. A perfect circular wave couples half its power to a linear antenna at any orientation, a fixed 3.01 dB. For a circular antenna with axial ratio AR dB, the voltage ratio is r = 10^(AR/20), the cross-polar discrimination is 20 log₁₀((r+1)/(r−1)) dB, and the loss to a linear antenna lies between 10 log₁₀(1+1/r²) and 10 log₁₀(1+r²) dB depending on its orientation. The tool ignores ground reflection, multipath, Faraday rotation along the path and antenna pattern effects; everything is calculated in this page.