Co- and cross-polarization refer to different orientations of antenna polarization in the context of electromagnetic wave propagation:
Co-polarization occurs when the transmitting and receiving antennas are aligned to the same polarization orientation – both antennas are vertically polarized (VV) or horizontally polarized (HH). In this configuration, the transmitted signal and the received signal have the same polarization state, maximizing signal resistance and minimizing polarization losses.
Cross polarization, on the other hand, occurs when the transmitting and receiving antennas are oriented with orthogonal (perpendicular) polarization states. For example, if an antenna transmits with vertical polarization (V) and the receiving antenna is polarized horizontally (H), this is referred to as VH polarization. Cross-polarization generally results in a reduction in signal resistance due to offset losses caused by the difference in orientation between the transmitting and receiving antennas.
The cross-polarization effect refers to the phenomenon where electromagnetic waves transmitted with a particular polarization state encounter an oriented receiving antenna with a different polarization state. This results in partial or significant signal attenuation because the receiving antenna is less sensitive to waves with polarization orthogonal to its orientation. The cross-polarization effect is crucial in antenna design and communication systems, where minimizing cross-polarization interference is essential to optimize signal efficiency and transmission efficiency.
In satellite communication, cross-polarization refers to the intentional use of orthogonal polarization states to transmit and receive signals between ground stations and satellites. This approach helps reduce interference between signals traveling on the same frequency band. Satellite antennas often use dual-polarization feed systems, allowing simultaneous transmission and reception of signals with horizontal and vertical polarizations. Cross-polarization in satellite communication helps improve system performance by mitigating co-channel interference and improving signal quality and reliability, especially in environments with high electromagnetic interference or signal noise .