Impact of polarization impurity on compact antenna array receiver for satellite navigation systems

We present a decoupled and matched four-element L1-band antenna array with an inter-element separation of a quarter of the free-space wavelength. We study the impact of polarization impurity in terms of the receiver's equivalent carrier-to-interference-plus-noise ratio when impinged with different numbers of diametrically polarized interferers. We observe that strong polarization impurity of the designed circular compact eigenmode antenna array, particularly for the high-order eigenmodes, reduces the available degrees-of-freedom for nulling by half in the presence of linear-polarized interferers with 40-dB interferer-to-signal power ratio.