When the polarization of the downcoming wave changes in relation to the receiving antenna, what is this variation in field intensity called?

The variation in field intensity caused by changes in the polarization of the downcoming wave relative to the receiving antenna is known as polarization fading. This phenomenon occurs when the polarization state of the incoming wave does not match the polarization of the antenna, leading to a decrease in signal strength. Antennas are typically designed to receive signals of a specific polarization—either vertical or horizontal. If the incoming wave has a different polarization, the efficiency of the antenna in capturing that signal diminishes, resulting in variability in the field intensity received.

By understanding the relationship between antenna polarization and wave polarization, it becomes clear how mismatches can lead to fluctuations in signal strength, which is what constitutes polarization fading. This knowledge is essential for optimizing communication systems, especially in scenarios where signal quality is critical.